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The electromagnetic spectrum: It’s more than visible light

The different forms of radiation in the electromagnetic spectrum.
The light we can see with our eyes is part of a range of radiation known as the electromagnetic spectrum. Shorter wavelengths of light are higher energy, and longer wavelengths of light are lower energy. The Hubble Space Telescope sees primarily visible light (indicated here by the rainbow), as well as some infrared and ultraviolet radiation. Image via NASA/ JHUAPL/ SwRI.
  • The electromagnetic spectrum includes a range of all types of light, not just what we can see. This range – going from radio waves to gamma rays – is mostly invisible to our eyes.
  • Our eyes see just visible light, which includes colors from red to violet. Different colors represent different wavelengths!
  • Astronomers use the entire spectrum of radiation from stars and other objects to study outer space. For example, radio waves help map galaxies, while infrared can see through dust clouds and identify cool stars.

The electromagnetic spectrum

When you think of light, you probably think of what your eyes can see. However, the light our human eyes can detect is only a sliver of the total amount of light that’s out there. So, the electromagnetic spectrum is the term scientists use to describe the entire range of light that exists. From radio waves to gamma rays, most of the light in the universe is, in fact, invisible to us.

Light is a wave of alternating electric and magnetic fields. The propagation of light isn’t much different than waves crossing an ocean. Like any other wave, light has a few fundamental properties that describe it. For example, one is its frequency, measured in hertz (Hz), which counts the number of waves that pass by a point in one second. Another closely related property is its wavelength: the distance from the peak of one wave to the peak of the next. In fact, these two attributes are inversely related. The larger the frequency, the smaller the wavelength, and vice versa.

Our eyes see visible light

The electromagnetic waves your eyes detect – visible light – oscillate between 400 and 790 terahertz (THz). To put it another way, that’s several hundred trillion times a second. As an illustration, the wavelengths are roughly the size of a large virus: 390 – 750 nanometers (1 nanometer = 1 billionth of a meter; a meter is about 39 inches long). Our brain interprets the various wavelengths of light as different colors. For example, red has the longest wavelength, and violet the shortest. When we pass sunlight through a prism, we see that it’s actually composed of many wavelengths of light. So the prism creates a rainbow by redirecting each wavelength out at a slightly different angle.

Diagram of spectrun showing scale of wavelengths from radio to gamma rays.
The entire electromagnetic spectrum is much more than just visible light. It encompasses a range of wavelengths of energy that our human eyes can’t see. Image via Wikimedia Commons.

But light doesn’t stop at red or violet. Indeed, just like there are sounds we can’t hear, there is an enormous range of light that our eyes can’t detect. In general, the longer wavelengths come from the coolest and darkest regions of space. Meanwhile, the shorter wavelengths measure extremely energetic phenomena.

The coolest part of the electromagnetic spectrum

Astronomers use the entire electromagnetic spectrum to observe a variety of things. Radio waves and microwaves are the longest wavelengths and lowest energies of light. With this in mind, they are used to peer inside dense interstellar clouds and track the motion of cold, dark gas. Radio telescopes have been used to map the structure of our galaxy. Additionally, microwave telescopes are sensitive to the remnant glow of the Big Bang.

Large wispy oval, red on one end, blue on the other.
This image from the Very Large Baseline Array (VLBA) shows what the galaxy M33 would look like if you could see it in radio waves. This image maps atomic hydrogen gas in the galaxy. The different colors map velocities in the gas: red shows gas moving away from us, blue is moving towards us. Image via NRAO/ AUI.

Infrared telescopes excel at finding cool, dim stars, slicing through interstellar dust bands. Plus, they even measure the temperatures of planets in other solar systems. The wavelengths of infrared light are long enough to navigate through clouds that would otherwise block our view. By using large infrared telescopes, astronomers peer through the dust lanes of our galaxy into the Milky Way’s core.

Dense starfield with bright patches, streaks and blobs.
This image from the Hubble and Spitzer space telescopes shows the central 300 light-years of our Milky Way galaxy, as we would see it if our eyes could see infrared energy. The image reveals massive star clusters and swirling gas clouds. Image via NASA/ ESA/ JPL/ Q.D. Wang/ S. Stolovy.

Most stars emit visible light

The majority of stars emit most of their electromagnetic energy as visible light, the tiny portion of the spectrum to which our eyes are sensitive. And, because wavelength correlates with energy, the color of a star tells us how hot it is: red stars are coolest, blue are hottest. On the other hand, the coldest of stars emit hardly any visible light at all; they can only be seen with infrared telescopes.

The more energetic ultraviolet light

Then at wavelengths shorter than violet, we find the ultraviolet, or UV, light. You may be familiar with UV from its ability to give you a sunburn. Astronomers use it to hunt out the most energetic of stars and identify regions of star birth. When viewing distant galaxies with UV telescopes, most of the stars and gas disappear, and all the stellar nurseries pop into view.

Oblique spiral with yellow center and arms made of thousands of shining pale blue dots.
A view of the spiral galaxy M81 in the ultraviolet, made possible by the GALEX space observatory. The bright regions show stellar nurseries in the spiral arms. Image via NASA.

Highest energy light: X-ray and Gamma Ray

Then, beyond UV come the highest energies in the electromagnetic spectrum: X-rays and gamma rays. Our atmosphere blocks this light, so astronomers must rely on telescopes in space to see the X-ray and gamma ray universe. X-rays come from exotic neutron stars, or from the vortex of superheated material spiraling around a black hole. As well as, from diffuse clouds of gas in galactic clusters that are heated to many millions of degrees.

Meanwhile, gamma rays – the shortest wavelength of light and deadly to humans – unveil violent events. And these include supernova explosions, cosmic radioactive decay and even the destruction of antimatter. Gamma ray bursts are among the most energetic singular events in the universe. Or they are a brief flickering of gamma ray light from distant galaxies when a star explodes and creates a black hole.

Hand-shaped blue gas cloud with crown of yellow-orange spots above finger end.
If you could see in X-rays, over long distances, you’d see this view of the nebula surrounding pulsar PSR B1509-58. This image is from the Chandra X-ray Observatory. Located 17,000 light-years away, the pulsar is the rapidly spinning remnant of a stellar core left behind after a supernova. Image via NASA.

See the difference for yourself

Bottom line: The electromagnetic spectrum describes all the wavelengths of light, both seen and unseen.

The post The electromagnetic spectrum: It’s more than visible light first appeared on EarthSky.



from EarthSky https://ift.tt/OqeTLxr
The different forms of radiation in the electromagnetic spectrum.
The light we can see with our eyes is part of a range of radiation known as the electromagnetic spectrum. Shorter wavelengths of light are higher energy, and longer wavelengths of light are lower energy. The Hubble Space Telescope sees primarily visible light (indicated here by the rainbow), as well as some infrared and ultraviolet radiation. Image via NASA/ JHUAPL/ SwRI.
  • The electromagnetic spectrum includes a range of all types of light, not just what we can see. This range – going from radio waves to gamma rays – is mostly invisible to our eyes.
  • Our eyes see just visible light, which includes colors from red to violet. Different colors represent different wavelengths!
  • Astronomers use the entire spectrum of radiation from stars and other objects to study outer space. For example, radio waves help map galaxies, while infrared can see through dust clouds and identify cool stars.

The electromagnetic spectrum

When you think of light, you probably think of what your eyes can see. However, the light our human eyes can detect is only a sliver of the total amount of light that’s out there. So, the electromagnetic spectrum is the term scientists use to describe the entire range of light that exists. From radio waves to gamma rays, most of the light in the universe is, in fact, invisible to us.

Light is a wave of alternating electric and magnetic fields. The propagation of light isn’t much different than waves crossing an ocean. Like any other wave, light has a few fundamental properties that describe it. For example, one is its frequency, measured in hertz (Hz), which counts the number of waves that pass by a point in one second. Another closely related property is its wavelength: the distance from the peak of one wave to the peak of the next. In fact, these two attributes are inversely related. The larger the frequency, the smaller the wavelength, and vice versa.

Our eyes see visible light

The electromagnetic waves your eyes detect – visible light – oscillate between 400 and 790 terahertz (THz). To put it another way, that’s several hundred trillion times a second. As an illustration, the wavelengths are roughly the size of a large virus: 390 – 750 nanometers (1 nanometer = 1 billionth of a meter; a meter is about 39 inches long). Our brain interprets the various wavelengths of light as different colors. For example, red has the longest wavelength, and violet the shortest. When we pass sunlight through a prism, we see that it’s actually composed of many wavelengths of light. So the prism creates a rainbow by redirecting each wavelength out at a slightly different angle.

Diagram of spectrun showing scale of wavelengths from radio to gamma rays.
The entire electromagnetic spectrum is much more than just visible light. It encompasses a range of wavelengths of energy that our human eyes can’t see. Image via Wikimedia Commons.

But light doesn’t stop at red or violet. Indeed, just like there are sounds we can’t hear, there is an enormous range of light that our eyes can’t detect. In general, the longer wavelengths come from the coolest and darkest regions of space. Meanwhile, the shorter wavelengths measure extremely energetic phenomena.

The coolest part of the electromagnetic spectrum

Astronomers use the entire electromagnetic spectrum to observe a variety of things. Radio waves and microwaves are the longest wavelengths and lowest energies of light. With this in mind, they are used to peer inside dense interstellar clouds and track the motion of cold, dark gas. Radio telescopes have been used to map the structure of our galaxy. Additionally, microwave telescopes are sensitive to the remnant glow of the Big Bang.

Large wispy oval, red on one end, blue on the other.
This image from the Very Large Baseline Array (VLBA) shows what the galaxy M33 would look like if you could see it in radio waves. This image maps atomic hydrogen gas in the galaxy. The different colors map velocities in the gas: red shows gas moving away from us, blue is moving towards us. Image via NRAO/ AUI.

Infrared telescopes excel at finding cool, dim stars, slicing through interstellar dust bands. Plus, they even measure the temperatures of planets in other solar systems. The wavelengths of infrared light are long enough to navigate through clouds that would otherwise block our view. By using large infrared telescopes, astronomers peer through the dust lanes of our galaxy into the Milky Way’s core.

Dense starfield with bright patches, streaks and blobs.
This image from the Hubble and Spitzer space telescopes shows the central 300 light-years of our Milky Way galaxy, as we would see it if our eyes could see infrared energy. The image reveals massive star clusters and swirling gas clouds. Image via NASA/ ESA/ JPL/ Q.D. Wang/ S. Stolovy.

Most stars emit visible light

The majority of stars emit most of their electromagnetic energy as visible light, the tiny portion of the spectrum to which our eyes are sensitive. And, because wavelength correlates with energy, the color of a star tells us how hot it is: red stars are coolest, blue are hottest. On the other hand, the coldest of stars emit hardly any visible light at all; they can only be seen with infrared telescopes.

The more energetic ultraviolet light

Then at wavelengths shorter than violet, we find the ultraviolet, or UV, light. You may be familiar with UV from its ability to give you a sunburn. Astronomers use it to hunt out the most energetic of stars and identify regions of star birth. When viewing distant galaxies with UV telescopes, most of the stars and gas disappear, and all the stellar nurseries pop into view.

Oblique spiral with yellow center and arms made of thousands of shining pale blue dots.
A view of the spiral galaxy M81 in the ultraviolet, made possible by the GALEX space observatory. The bright regions show stellar nurseries in the spiral arms. Image via NASA.

Highest energy light: X-ray and Gamma Ray

Then, beyond UV come the highest energies in the electromagnetic spectrum: X-rays and gamma rays. Our atmosphere blocks this light, so astronomers must rely on telescopes in space to see the X-ray and gamma ray universe. X-rays come from exotic neutron stars, or from the vortex of superheated material spiraling around a black hole. As well as, from diffuse clouds of gas in galactic clusters that are heated to many millions of degrees.

Meanwhile, gamma rays – the shortest wavelength of light and deadly to humans – unveil violent events. And these include supernova explosions, cosmic radioactive decay and even the destruction of antimatter. Gamma ray bursts are among the most energetic singular events in the universe. Or they are a brief flickering of gamma ray light from distant galaxies when a star explodes and creates a black hole.

Hand-shaped blue gas cloud with crown of yellow-orange spots above finger end.
If you could see in X-rays, over long distances, you’d see this view of the nebula surrounding pulsar PSR B1509-58. This image is from the Chandra X-ray Observatory. Located 17,000 light-years away, the pulsar is the rapidly spinning remnant of a stellar core left behind after a supernova. Image via NASA.

See the difference for yourself

Bottom line: The electromagnetic spectrum describes all the wavelengths of light, both seen and unseen.

The post The electromagnetic spectrum: It’s more than visible light first appeared on EarthSky.



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The 2nd eclipse season of 2026 is underway

Diagram with sun at the center and many blue disks in a plane around it, with dots for Earth and moon on each.
Here are the eclipse seasons of 2026, shown in bold. The sun is at the center of this diagram. The Earth is shown as a white dot in the center of each blue disk. And the moon’s orbit defines the blue disks surrounding each white dot. The moon is either sunward from Earth (new moon) or outward from it (full moon). Small arrows at the edge of the blue disks show the moon’s course over 7 days. Image via Guy Ottewell’s Astronomical Calendar 2026. Used with permission.

2nd eclipse season of 2026

The 2nd eclipse season of 2026 is underway. An eclipse season is an approximately 35-day period during which it’s inevitable that at least two (and possibly three) eclipses will occur. There will be a total solar eclipse on August 12, 2026, followed two weeks later by a partial lunar eclipse on August 28, 2026.

The first eclipse season of 2026 featured two eclipses, an annular or “ring of fire” solar eclipse on February 17 and a total lunar eclipse on March 2-3.

During an eclipse season, the Earth, moon and sun line up in space. Eclipse seasons recur about every 173 days (somewhat shy of every six calendar months), when the sun aligns with one of the moon’s orbital nodes — the two points where the plane of the moon’s orbit crosses the plane of Earth’s orbit around the sun. The moon has to be at a node at either full or new moon, in order for an eclipse to occur.

A full moon at a lunar node means a lunar eclipse. A new moon at a node means a solar eclipse.

Why don’t we see every eclipse?

So we have two eclipse seasons per year (usually), giving us have at least four eclipses per year and sometimes more. But – unless we become eclipse chasers – most of us don’t see that many eclipses. To see a lunar eclipse, the full moon has to be above your horizon. And that can only happen at night, or close to night, because a full moon is opposite the sun. Night falls for half of Earth at once. So, generally speaking, half of Earth can see a lunar eclipse at once.

Solar eclipses are harder to catch. A total solar eclipse can be seen only from a narrow track along Earth’s surface. The accompanying partial solar eclipse can be seen only in areas adjacent to that track.

So you have to be in the right location on Earth’s surface to see a lunar or solar eclipse. But lunar eclipses are easier to catch than solar eclipses.

The moon looks deep red on the right side and light red on the left side.
View at EarthSky Community Photos. | Catherine Hyde in Cambria, California, captured this stunning telescope image of the total lunar eclipse on March 3, 2026. Thank you, Catherine! See more incredible lunar eclipse images below.

See spectacular total lunar eclipse images from March 2-3, 2026

A glowing crescent low in a dark, reddish sky and some streaks of clouds over a level horizon, maybe the sea.
View at EarthSky Community Photos. | Iaroslav Kourzenkov in Halifax, Nova Scotia, Canada, captured a partial solar eclipse on March 29, 2025. Iaroslav wrote: “Witnessed a rare beauty this morning! Caught the stunning partial solar eclipse at sunrise and managed to snap a few photos.” Thank you, Iaroslav!

What causes an eclipse season?

Astronomy is all about cycles. When you learn to watch the night sky, you’ll begin to notice the many cycles of the sky.

And, of course, eclipses come in cycles, too. Consider a scenario where the moon orbited Earth on the same plane as the Earth orbits the sun. Then we’d have a solar eclipse at every new moon, and a lunar eclipse at every full moon.

But, in reality, the plane of the moon’s orbit is inclined by 5 degrees to the ecliptic (Earth’s orbital plane). Most of the time, the new moon or full moon swings too far north, or south, of the ecliptic for an eclipse to take place.

For instance, in the year 2026, we will have 12 new moons and 13 full moons, but only two solar eclipses and two lunar eclipses.

Diagram of Earth, moon, and sun lined up showing the moon's shadow on Earth.
Eclipses are all about alignments. In a solar eclipse, the sun, moon and Earth line up, with the moon in the middle. Image via NASA.
Eclipse season: Diagram of Earth, moon, and sun lined up, Earth between the sun and the moon, shading the moon.
In a lunar eclipse, the sun, Earth and moon line up, with the Earth in the middle. Image via NASA.

When lunar nodes point at the sun

So, as the moon orbits Earth, the moon crosses the ecliptic (Earth’s orbital plane) twice each month. Those crossing points are the nodes. If the moon is going from south to north, it’s called the moon’s ascending node. If the moon is moving from north to south, it’s called the moon’s descending node.

But, for an eclipse to take place, that crossing point – or lunar node – must be pointed at the sun. And that momentous crossing marks the middle of the eclipse season. Maybe you can see that the alignment of the moon, sun and Earth is most exact when an eclipse happens at the middle of an eclipse season, in other words, when there’s a new or full moon precisely at a node crossing. On the other hand, the alignment of the moon, sun and Earth is least exact when a new or full moon happens at the start or the end of an eclipse season. A lunar eclipse happening early or late in the eclipse season gives us a penumbral lunar eclipse, where the outer, lighter shadow of the Earth brushes the moon’s face. And any solar eclipse happening early or late in the eclipse season is a skimpy partial eclipse.

Read more: Node passages of the moon: 2001 to 2100

Diagram of moon in 4 positions around Earth, showing that the moon orbit is slightly oblique to Earth orbit.
View larger. | Nodal precession of the lunar nodes as the Earth revolves around the sun causes an eclipse season approximately every 6 months. Image via Nela/ Wikimedia Commons.

2 or 3 eclipses in one eclipse season?

An eclipse season most often presents only two eclipses. However, if the first eclipse falls early in the eclipse season, then it’s possible for a third eclipse to occur before the eclipse season ends.

For example, the last time three eclipses happened in one eclipse season was June-July 2020:

June 5, 2020: Penumbral lunar eclipse
June 21, 2020: Annular solar eclipse
July 5, 2020: Penumbral lunar eclipse

Likewise, the next time three eclipses will occur in one eclipse season will be July-August 2027:

July 18, 2027: Penumbral lunar eclipse
August 2, 2027: Total solar eclipse
August 17, 2027: Penumbral lunar eclipse

Eclipse season terminology

With this in mind, here are some words you need to know to understand eclipse seasons: lunar nodes and ecliptic. The ecliptic is the plane of the Earth’s orbit around the sun. A lunar node is the point where, in its monthly orbit of Earth, the moon’s orbit intersects that plane. An eclipse season is when – from Earth’s perspective – the sun is close enough to a lunar node to allow an eclipse to take place. If the sun is close to a lunar node at full moon, we see a lunar eclipse. If the sun is close to a lunar node at new moon, we see a solar eclipse.

To put it another way, if the moon turns new or full in close concert with the moon’s crossing of one of its nodes, then an eclipse is not only possible, but inevitable.

Diagram of orbit of moon showing that it is slightly oblique, and nodes marked where it crosses the ecliptic.
The moon’s orbit around Earth is inclined 5 degrees to Earth’s orbit around the sun, so the moon crosses the Earth’s orbital plane twice a month at points called nodes. Every 173.3 days, the line of nodes points at the sun, which is the middle of the approximate 5-week eclipse season (highlighted in gray). During any eclipse season, there is always at least 1 solar eclipse and 1 lunar eclipse, occurring within one fortnight of the other. If the 1st eclipse arrives early enough in the eclipse season, 3 eclipses can fit within a lunar month, and up to 7 eclipses occur in one year’s time. Image via SuperManu/ Wikimedia Commons.

Minimum of 4 eclipses in one year

A lunar month (period of time between successive new moons or successive full moons) is about 29.5 days long. So a minimum of two eclipses (one solar and one lunar, in either order) happens in one eclipse season. A maximum of three eclipses is possible (either lunar/solar/lunar or solar/lunar/solar), though the first eclipse of the eclipse season has to come quite early to allow for a third eclipse near the end.

So a minimum of two lunar eclipses and two solar eclipses occurs in one calendar year. Yet, depending on how the eclipse seasons and lunar phases align, it’s possible to also have five, six or seven eclipses in one year.

For the maximum of seven eclipses to occur in one calendar year, the first eclipse must come in early January. That leaves enough room for the seventh eclipse in late December. In one scenario, an eclipse season sporting two eclipses comes early in the year and late in the year. The middle eclipse season stages three eclipses.

It’s quite rare for seven eclipses to occur in one calendar year, however. Seven eclipses last happened in the year 1982, and will next occur in the year 2038.

Maximum of 7 eclipses in one year

Also, it’s remotely possible for a calendar year to sport two eclipse seasons with three eclipses each, and one eclipse from an eclipse season that straddles into the previous or following year. Click in to see two examples, the years 1935 and 1879-80.

A very bright crescent low in the dark sky, also reflected in dark water.
View at EarthSky Community Photos. | David Chapman in Seaforth, Nova Scotia, Canada, captured a partial solar eclipse on March 29, 2025. David wrote: “I drove to a coastal location northeast of Halifax to avoid the encroaching cloud bank. I observed a point-like green flash as the upper cusp of the crescent appeared at 7:00 ADT. Photo is at peak eclipse and is a bit overexposed.” Thank you, David!
Large pink-orange full moon surrounded by smaller moons in different phases of the eclipse.
View at EarthSky Community Photos. | Kathy Hunter caught these views of the lunar eclipse on March 14, 2025, from West Virginia. Kathy wrote: “My first composite!” Thank you, Kathy.

Bottom line: Eclipse seasons are periods during which eclipses not only can take place, but must take place. There’s a minimum of two eclipses in one eclipse season and a maximum of seven eclipses possible in a calendar year. In 2026, the 2nd eclipse season is in August with a total solar eclipse and a partial lunar eclipse.

Details here: Total solar eclipse dazzles observers on August 12, 2026

Read more: Partial lunar eclipse of the August 27-28 full Sturgeon Moon

Read more: New mission could create artificial solar eclipses in space

The post The 2nd eclipse season of 2026 is underway first appeared on EarthSky.



from EarthSky https://ift.tt/BOgNJYV
Diagram with sun at the center and many blue disks in a plane around it, with dots for Earth and moon on each.
Here are the eclipse seasons of 2026, shown in bold. The sun is at the center of this diagram. The Earth is shown as a white dot in the center of each blue disk. And the moon’s orbit defines the blue disks surrounding each white dot. The moon is either sunward from Earth (new moon) or outward from it (full moon). Small arrows at the edge of the blue disks show the moon’s course over 7 days. Image via Guy Ottewell’s Astronomical Calendar 2026. Used with permission.

2nd eclipse season of 2026

The 2nd eclipse season of 2026 is underway. An eclipse season is an approximately 35-day period during which it’s inevitable that at least two (and possibly three) eclipses will occur. There will be a total solar eclipse on August 12, 2026, followed two weeks later by a partial lunar eclipse on August 28, 2026.

The first eclipse season of 2026 featured two eclipses, an annular or “ring of fire” solar eclipse on February 17 and a total lunar eclipse on March 2-3.

During an eclipse season, the Earth, moon and sun line up in space. Eclipse seasons recur about every 173 days (somewhat shy of every six calendar months), when the sun aligns with one of the moon’s orbital nodes — the two points where the plane of the moon’s orbit crosses the plane of Earth’s orbit around the sun. The moon has to be at a node at either full or new moon, in order for an eclipse to occur.

A full moon at a lunar node means a lunar eclipse. A new moon at a node means a solar eclipse.

Why don’t we see every eclipse?

So we have two eclipse seasons per year (usually), giving us have at least four eclipses per year and sometimes more. But – unless we become eclipse chasers – most of us don’t see that many eclipses. To see a lunar eclipse, the full moon has to be above your horizon. And that can only happen at night, or close to night, because a full moon is opposite the sun. Night falls for half of Earth at once. So, generally speaking, half of Earth can see a lunar eclipse at once.

Solar eclipses are harder to catch. A total solar eclipse can be seen only from a narrow track along Earth’s surface. The accompanying partial solar eclipse can be seen only in areas adjacent to that track.

So you have to be in the right location on Earth’s surface to see a lunar or solar eclipse. But lunar eclipses are easier to catch than solar eclipses.

The moon looks deep red on the right side and light red on the left side.
View at EarthSky Community Photos. | Catherine Hyde in Cambria, California, captured this stunning telescope image of the total lunar eclipse on March 3, 2026. Thank you, Catherine! See more incredible lunar eclipse images below.

See spectacular total lunar eclipse images from March 2-3, 2026

A glowing crescent low in a dark, reddish sky and some streaks of clouds over a level horizon, maybe the sea.
View at EarthSky Community Photos. | Iaroslav Kourzenkov in Halifax, Nova Scotia, Canada, captured a partial solar eclipse on March 29, 2025. Iaroslav wrote: “Witnessed a rare beauty this morning! Caught the stunning partial solar eclipse at sunrise and managed to snap a few photos.” Thank you, Iaroslav!

What causes an eclipse season?

Astronomy is all about cycles. When you learn to watch the night sky, you’ll begin to notice the many cycles of the sky.

And, of course, eclipses come in cycles, too. Consider a scenario where the moon orbited Earth on the same plane as the Earth orbits the sun. Then we’d have a solar eclipse at every new moon, and a lunar eclipse at every full moon.

But, in reality, the plane of the moon’s orbit is inclined by 5 degrees to the ecliptic (Earth’s orbital plane). Most of the time, the new moon or full moon swings too far north, or south, of the ecliptic for an eclipse to take place.

For instance, in the year 2026, we will have 12 new moons and 13 full moons, but only two solar eclipses and two lunar eclipses.

Diagram of Earth, moon, and sun lined up showing the moon's shadow on Earth.
Eclipses are all about alignments. In a solar eclipse, the sun, moon and Earth line up, with the moon in the middle. Image via NASA.
Eclipse season: Diagram of Earth, moon, and sun lined up, Earth between the sun and the moon, shading the moon.
In a lunar eclipse, the sun, Earth and moon line up, with the Earth in the middle. Image via NASA.

When lunar nodes point at the sun

So, as the moon orbits Earth, the moon crosses the ecliptic (Earth’s orbital plane) twice each month. Those crossing points are the nodes. If the moon is going from south to north, it’s called the moon’s ascending node. If the moon is moving from north to south, it’s called the moon’s descending node.

But, for an eclipse to take place, that crossing point – or lunar node – must be pointed at the sun. And that momentous crossing marks the middle of the eclipse season. Maybe you can see that the alignment of the moon, sun and Earth is most exact when an eclipse happens at the middle of an eclipse season, in other words, when there’s a new or full moon precisely at a node crossing. On the other hand, the alignment of the moon, sun and Earth is least exact when a new or full moon happens at the start or the end of an eclipse season. A lunar eclipse happening early or late in the eclipse season gives us a penumbral lunar eclipse, where the outer, lighter shadow of the Earth brushes the moon’s face. And any solar eclipse happening early or late in the eclipse season is a skimpy partial eclipse.

Read more: Node passages of the moon: 2001 to 2100

Diagram of moon in 4 positions around Earth, showing that the moon orbit is slightly oblique to Earth orbit.
View larger. | Nodal precession of the lunar nodes as the Earth revolves around the sun causes an eclipse season approximately every 6 months. Image via Nela/ Wikimedia Commons.

2 or 3 eclipses in one eclipse season?

An eclipse season most often presents only two eclipses. However, if the first eclipse falls early in the eclipse season, then it’s possible for a third eclipse to occur before the eclipse season ends.

For example, the last time three eclipses happened in one eclipse season was June-July 2020:

June 5, 2020: Penumbral lunar eclipse
June 21, 2020: Annular solar eclipse
July 5, 2020: Penumbral lunar eclipse

Likewise, the next time three eclipses will occur in one eclipse season will be July-August 2027:

July 18, 2027: Penumbral lunar eclipse
August 2, 2027: Total solar eclipse
August 17, 2027: Penumbral lunar eclipse

Eclipse season terminology

With this in mind, here are some words you need to know to understand eclipse seasons: lunar nodes and ecliptic. The ecliptic is the plane of the Earth’s orbit around the sun. A lunar node is the point where, in its monthly orbit of Earth, the moon’s orbit intersects that plane. An eclipse season is when – from Earth’s perspective – the sun is close enough to a lunar node to allow an eclipse to take place. If the sun is close to a lunar node at full moon, we see a lunar eclipse. If the sun is close to a lunar node at new moon, we see a solar eclipse.

To put it another way, if the moon turns new or full in close concert with the moon’s crossing of one of its nodes, then an eclipse is not only possible, but inevitable.

Diagram of orbit of moon showing that it is slightly oblique, and nodes marked where it crosses the ecliptic.
The moon’s orbit around Earth is inclined 5 degrees to Earth’s orbit around the sun, so the moon crosses the Earth’s orbital plane twice a month at points called nodes. Every 173.3 days, the line of nodes points at the sun, which is the middle of the approximate 5-week eclipse season (highlighted in gray). During any eclipse season, there is always at least 1 solar eclipse and 1 lunar eclipse, occurring within one fortnight of the other. If the 1st eclipse arrives early enough in the eclipse season, 3 eclipses can fit within a lunar month, and up to 7 eclipses occur in one year’s time. Image via SuperManu/ Wikimedia Commons.

Minimum of 4 eclipses in one year

A lunar month (period of time between successive new moons or successive full moons) is about 29.5 days long. So a minimum of two eclipses (one solar and one lunar, in either order) happens in one eclipse season. A maximum of three eclipses is possible (either lunar/solar/lunar or solar/lunar/solar), though the first eclipse of the eclipse season has to come quite early to allow for a third eclipse near the end.

So a minimum of two lunar eclipses and two solar eclipses occurs in one calendar year. Yet, depending on how the eclipse seasons and lunar phases align, it’s possible to also have five, six or seven eclipses in one year.

For the maximum of seven eclipses to occur in one calendar year, the first eclipse must come in early January. That leaves enough room for the seventh eclipse in late December. In one scenario, an eclipse season sporting two eclipses comes early in the year and late in the year. The middle eclipse season stages three eclipses.

It’s quite rare for seven eclipses to occur in one calendar year, however. Seven eclipses last happened in the year 1982, and will next occur in the year 2038.

Maximum of 7 eclipses in one year

Also, it’s remotely possible for a calendar year to sport two eclipse seasons with three eclipses each, and one eclipse from an eclipse season that straddles into the previous or following year. Click in to see two examples, the years 1935 and 1879-80.

A very bright crescent low in the dark sky, also reflected in dark water.
View at EarthSky Community Photos. | David Chapman in Seaforth, Nova Scotia, Canada, captured a partial solar eclipse on March 29, 2025. David wrote: “I drove to a coastal location northeast of Halifax to avoid the encroaching cloud bank. I observed a point-like green flash as the upper cusp of the crescent appeared at 7:00 ADT. Photo is at peak eclipse and is a bit overexposed.” Thank you, David!
Large pink-orange full moon surrounded by smaller moons in different phases of the eclipse.
View at EarthSky Community Photos. | Kathy Hunter caught these views of the lunar eclipse on March 14, 2025, from West Virginia. Kathy wrote: “My first composite!” Thank you, Kathy.

Bottom line: Eclipse seasons are periods during which eclipses not only can take place, but must take place. There’s a minimum of two eclipses in one eclipse season and a maximum of seven eclipses possible in a calendar year. In 2026, the 2nd eclipse season is in August with a total solar eclipse and a partial lunar eclipse.

Details here: Total solar eclipse dazzles observers on August 12, 2026

Read more: Partial lunar eclipse of the August 27-28 full Sturgeon Moon

Read more: New mission could create artificial solar eclipses in space

The post The 2nd eclipse season of 2026 is underway first appeared on EarthSky.



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Solar eclipse: Top 5 tips for photographing an eclipse

Solar eclipse: Group of people standing in a grassy field, with trees in the distance and a the blocked-out sun above them.
People watch a partial solar eclipse in Belfast, Northern Ireland, on March 20, 2015. Image via NASA/ Robin Cordiner.

Via Mara Johnson-Groh, NASA’s Goddard Space Flight Center

There’s a total solar eclipse on August 12, 2026, visible from parts of the Arctic, Greenland, Iceland and Spain. And it’ll be visible as a partial eclipse from much of western Europe and North America.

Here’s a unique photo tip: During this total solar eclipse, you might catch a Perseid meteor! That’s because the Perseid shower is reaching its peak on August 12-13.

Solar eclipses offer a unique opportunity for scientists studying the shadow of the moon. And it’s also a perfect opportunity to capture unforgettable images. Try out these tips for photographing the eclipse.

1. Safety first

To take images as the sun is being eclipsed, you’ll need to use a special solar filter to protect your camera’s sensor. That’s just like you’ll need a pair of eclipse glasses to protect your own eyes. However, at totality, when the moon completely blocks the sun, make sure to remove the filter so you can see the sun’s outer atmosphere, the corona.

How to watch a solar eclipse safely

Having a few other pieces of equipment can also come in handy during the eclipse. Using a tripod can help you stabilize the camera and avoid taking blurry images thanks to the low lighting. Additionally, using a delayed shutter release timer will allow you to snap shots without jiggling the camera.

Solid black circle with with white streamers all around, in four concentric boxes around it.
View at EarthSky Community Photos. | Shaun Tarpley in Shawnee National Forest, Illinois, wrote: “I created this using a 9-image bracket series I took during the 2017 total solar eclipse and overlaid frames indicating the relative field-of-view of common focal lengths to help photographers planning to photograph the 2024 eclipse to visualize what focal length is optimum for their imaging goals. It is a quick way to visualize the differences.” Thank you, Shaun!

2. Any camera is a good camera

Taking a stunning photo has more to do with the photographer than the camera. Whether you have a high-end DLSR or a camera phone, you can take great photos during the eclipse. After all, the best piece of equipment you can have is a good eye and a vision for the image you want to create.

If you don’t have a telephoto zoom lens, focus on taking landscape shots, which capture the changing environment.

During totality, the moon completely covers the sun. If you do have a telephoto lens with a solar filter, you’ll be able to see and photograph the structures in the sun’s corona.

Very many scattered rings of light on a deep-red brick pavement.
Robert Asher in Artesia, New Mexico, captured these images of the sun in a ring around the moon – at mid-eclipse – on October 14, 2023. When you see crescents dancing under the trees during an eclipse of the sun, it’s because tree leaves are creating natural pinhole cameras that project the image of the sun and moon. Thank you, Robert! Used with permission.

3. Look up, down, all around

While the sun is the most commanding element of an eclipse, remember to look around you. As the moon slips in front of the sun, the landscape will be bathed in long shadows, creating eerie lighting across the landscape. Light filtering through the overlapping leaves of trees will create natural pinholes, producing mini eclipse replicas on the ground. Everywhere you can point your camera can yield exceptional imagery, so be sure to compose some wide-angle photos that can capture your eclipse experience.

NASA photographer Bill Ingalls recommends focusing on the human experience of watching the eclipse. He said:

The real pictures are going to be of the people around you pointing, gawking and watching it. Those are going to be some great moments to capture to show the emotion of the whole thing.

4. Practice and plan

Be sure you know the capabilities of your camera before eclipse day. Most cameras, and even many camera phones, have adjustable exposures. These can help you darken or lighten your image during the tricky eclipse lighting. Make sure you know how to manually focus the camera for crisp shots.

For DSLR cameras, the best way to determine the correct exposure is to test settings on the uneclipsed sun beforehand using a solar filter. Using a fixed aperture of f/8 to f/16, try shutter speeds between 1/1000 to 1/4 second to find the optimal setting. You can then use that to take images during the partial stages of the eclipse. During totality, the corona has a wide range of brightness. So it’s best to use a fixed aperture and a range of exposures from approximately 1/1000 to 1 second without the solar filter. Then, put your solar filter back once totality has ended.

5. Share!

Share your eclipse experience with friends and family afterwards. Use the hashtag #Eclipse2026 on your favorite social media sites.

And share your pics with us at EarthSky here.

While you’re out perfecting your perfect eclipse shot, don’t forget to stop and look at the eclipse with your own eyes. Just remember to wear your eclipse glasses for all stages of the eclipse before and after totality!

Bottom line: Here are five tips for photographing the August 12, 2026, total solar eclipse.

Science news, night sky events and beautiful photos, all in one place. Click here to subscribe to our free daily newsletter.

Read more: April 8, 2024, total solar eclipse pics and video from the EarthSky community

Read more: Eclipse photos here! Annular solar eclipse October 14, 2023

The post Solar eclipse: Top 5 tips for photographing an eclipse first appeared on EarthSky.



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Solar eclipse: Group of people standing in a grassy field, with trees in the distance and a the blocked-out sun above them.
People watch a partial solar eclipse in Belfast, Northern Ireland, on March 20, 2015. Image via NASA/ Robin Cordiner.

Via Mara Johnson-Groh, NASA’s Goddard Space Flight Center

There’s a total solar eclipse on August 12, 2026, visible from parts of the Arctic, Greenland, Iceland and Spain. And it’ll be visible as a partial eclipse from much of western Europe and North America.

Here’s a unique photo tip: During this total solar eclipse, you might catch a Perseid meteor! That’s because the Perseid shower is reaching its peak on August 12-13.

Solar eclipses offer a unique opportunity for scientists studying the shadow of the moon. And it’s also a perfect opportunity to capture unforgettable images. Try out these tips for photographing the eclipse.

1. Safety first

To take images as the sun is being eclipsed, you’ll need to use a special solar filter to protect your camera’s sensor. That’s just like you’ll need a pair of eclipse glasses to protect your own eyes. However, at totality, when the moon completely blocks the sun, make sure to remove the filter so you can see the sun’s outer atmosphere, the corona.

How to watch a solar eclipse safely

Having a few other pieces of equipment can also come in handy during the eclipse. Using a tripod can help you stabilize the camera and avoid taking blurry images thanks to the low lighting. Additionally, using a delayed shutter release timer will allow you to snap shots without jiggling the camera.

Solid black circle with with white streamers all around, in four concentric boxes around it.
View at EarthSky Community Photos. | Shaun Tarpley in Shawnee National Forest, Illinois, wrote: “I created this using a 9-image bracket series I took during the 2017 total solar eclipse and overlaid frames indicating the relative field-of-view of common focal lengths to help photographers planning to photograph the 2024 eclipse to visualize what focal length is optimum for their imaging goals. It is a quick way to visualize the differences.” Thank you, Shaun!

2. Any camera is a good camera

Taking a stunning photo has more to do with the photographer than the camera. Whether you have a high-end DLSR or a camera phone, you can take great photos during the eclipse. After all, the best piece of equipment you can have is a good eye and a vision for the image you want to create.

If you don’t have a telephoto zoom lens, focus on taking landscape shots, which capture the changing environment.

During totality, the moon completely covers the sun. If you do have a telephoto lens with a solar filter, you’ll be able to see and photograph the structures in the sun’s corona.

Very many scattered rings of light on a deep-red brick pavement.
Robert Asher in Artesia, New Mexico, captured these images of the sun in a ring around the moon – at mid-eclipse – on October 14, 2023. When you see crescents dancing under the trees during an eclipse of the sun, it’s because tree leaves are creating natural pinhole cameras that project the image of the sun and moon. Thank you, Robert! Used with permission.

3. Look up, down, all around

While the sun is the most commanding element of an eclipse, remember to look around you. As the moon slips in front of the sun, the landscape will be bathed in long shadows, creating eerie lighting across the landscape. Light filtering through the overlapping leaves of trees will create natural pinholes, producing mini eclipse replicas on the ground. Everywhere you can point your camera can yield exceptional imagery, so be sure to compose some wide-angle photos that can capture your eclipse experience.

NASA photographer Bill Ingalls recommends focusing on the human experience of watching the eclipse. He said:

The real pictures are going to be of the people around you pointing, gawking and watching it. Those are going to be some great moments to capture to show the emotion of the whole thing.

4. Practice and plan

Be sure you know the capabilities of your camera before eclipse day. Most cameras, and even many camera phones, have adjustable exposures. These can help you darken or lighten your image during the tricky eclipse lighting. Make sure you know how to manually focus the camera for crisp shots.

For DSLR cameras, the best way to determine the correct exposure is to test settings on the uneclipsed sun beforehand using a solar filter. Using a fixed aperture of f/8 to f/16, try shutter speeds between 1/1000 to 1/4 second to find the optimal setting. You can then use that to take images during the partial stages of the eclipse. During totality, the corona has a wide range of brightness. So it’s best to use a fixed aperture and a range of exposures from approximately 1/1000 to 1 second without the solar filter. Then, put your solar filter back once totality has ended.

5. Share!

Share your eclipse experience with friends and family afterwards. Use the hashtag #Eclipse2026 on your favorite social media sites.

And share your pics with us at EarthSky here.

While you’re out perfecting your perfect eclipse shot, don’t forget to stop and look at the eclipse with your own eyes. Just remember to wear your eclipse glasses for all stages of the eclipse before and after totality!

Bottom line: Here are five tips for photographing the August 12, 2026, total solar eclipse.

Science news, night sky events and beautiful photos, all in one place. Click here to subscribe to our free daily newsletter.

Read more: April 8, 2024, total solar eclipse pics and video from the EarthSky community

Read more: Eclipse photos here! Annular solar eclipse October 14, 2023

The post Solar eclipse: Top 5 tips for photographing an eclipse first appeared on EarthSky.



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Aquila the Eagle soars along the Milky Way

Aquila the Eagle: Star chart of a stretched diamond shape with a tail from the wide edge, with labels.
Aquila the Eagle is home to the star Altair, which is one of the corners of the Summer Triangle. In addition, you can also use Aquila to starhop your way to the Wild Duck cluster in Scutum the Shield. Image via EarthSky.

The best time to see the constellation Aquila the Eagle in the evening sky is from July to November as it soars along the Milky Way. And, because our galaxy provides a starry backdrop, many clusters and nebulae lie within its borders. Aquila’s brightest star, Altair, is the southernmost corner star in the Summer Triangle. In mythology, Aquila carried Zeus’ thunderbolts for him.

The stars of Aquila the Eagle

The brightest star in Aquila is Alpha Aquilae, or Altair. At magnitude 0.76, it is one of the three bright stars that mark the corners of the Summer Triangle. Deneb and Vega are the other two and they lie higher in the sky, closer to the zenith on summer evenings. Altair lies just 17 light-years away from Earth.

Additionally, two moderately bright stars lie on either side of Altair. To the southeast is Beta Aquilae, or Alshain. This magnitude 3.71 star lies 45 light-years away. To the other side of Altair is Gamma Aquilae, or Tarazed. At magnitude 2.72, it’s brighter than Alshain but lies much farther away at 461 light-years. This trio of stars is found near the head of Aquila the Eagle.

Then, the star marking Aquila’s back is Delta Aquilae, at magnitude 3.36 and 50 light-years away. Likewise, Theta Aquilae marks the left wing. It shines at magnitude 3.26 from across 286 light-years. The right wing, that points to Vega, holds Zeta Aquilae at magnitude 2.99 and 83 light-years distant. Lastly, the star at the end of the tail of the Eagle is Lambda Aquilae at magnitude 3.43, lying 125 light-years away.

Star chart with stars in black on white and constellation lines in green.
The stars of Aquila the Eagle. The larger the dot, the brighter the star. Image via IAU/ Sky and Telescope/ Wikimedia Commons (CC BY 3.0).

Globular clusters

While there are no Messier objects in Aquila, there is still a lot to see, especially if you have a big enough telescope. For example, two globular clusters lie in Aquila: NGC 6749 and NGC 6760.

The two globular clusters are in the vicinity of Delta Aquilae. NGC 6760 shines at magnitude 9.1. Then, about 2 degrees farther away is NGC 6749 at magnitude 12.

In addition, several open clusters lie in Aquila, but most of them are faint. With this in mind, the best one to observe is NGC 6755, a 7.5-magnitude grouping found near the star marking the back of the Eagle. Another good open cluster to try for is NGC 6709, which, at magnitude 6.7, appears in binoculars. NGC 6709 is fairly near Zeta Aquilae, the upper wing of the Eagle. Between these two clusters is yet another cluster, NGC 6738. This sparse cluster is 8th magnitude.

Also, a lot of observers who come to Aquila use it to starhop to a cluster just over the border of the constellation Scutum the Shield. The Wild Duck Cluster, M11, shines at magnitude 6.3, making it brighter than any of the clusters in Aquila. Here’s how to find it.

Antique colored etching of a flying eagle near a fish and an archer, all scattered with stars.
Altair in Aquila the Eagle, with 2 smaller constellations nearby. Image via Wikipedia.

Nebulae of Aquila

A number of nebulae lie along the line that marks the body of the Eagle, but only one is bright enough to reach even 10th magnitude. NGC 6790 lies a little less than 2 degrees from the star that marks the back of the Eagle in the direction of its tail.

Good luck tracking down these tough-to-spot, faint objects in Aquila the Eagle. Or, you can always just scan the area in binoculars and see what materializes.

Photo of the starlit band of the Milky Way, with outlines for Scutum, Aquila the Eagle and Lyra.
View at EarthSky Community Photos. | Cecille Kennedy caught this image from the central Oregon coast. Notice how Aquila the Eagle soars along the Milky Way. Thank you, Cecille!

Bottom line: Aquila the Eagle is home to the bright star Altair, which forms one corner of the Summer Triangle. And you can see this constellation at its best in northern late summer or early fall evenings.

The post Aquila the Eagle soars along the Milky Way first appeared on EarthSky.



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Aquila the Eagle: Star chart of a stretched diamond shape with a tail from the wide edge, with labels.
Aquila the Eagle is home to the star Altair, which is one of the corners of the Summer Triangle. In addition, you can also use Aquila to starhop your way to the Wild Duck cluster in Scutum the Shield. Image via EarthSky.

The best time to see the constellation Aquila the Eagle in the evening sky is from July to November as it soars along the Milky Way. And, because our galaxy provides a starry backdrop, many clusters and nebulae lie within its borders. Aquila’s brightest star, Altair, is the southernmost corner star in the Summer Triangle. In mythology, Aquila carried Zeus’ thunderbolts for him.

The stars of Aquila the Eagle

The brightest star in Aquila is Alpha Aquilae, or Altair. At magnitude 0.76, it is one of the three bright stars that mark the corners of the Summer Triangle. Deneb and Vega are the other two and they lie higher in the sky, closer to the zenith on summer evenings. Altair lies just 17 light-years away from Earth.

Additionally, two moderately bright stars lie on either side of Altair. To the southeast is Beta Aquilae, or Alshain. This magnitude 3.71 star lies 45 light-years away. To the other side of Altair is Gamma Aquilae, or Tarazed. At magnitude 2.72, it’s brighter than Alshain but lies much farther away at 461 light-years. This trio of stars is found near the head of Aquila the Eagle.

Then, the star marking Aquila’s back is Delta Aquilae, at magnitude 3.36 and 50 light-years away. Likewise, Theta Aquilae marks the left wing. It shines at magnitude 3.26 from across 286 light-years. The right wing, that points to Vega, holds Zeta Aquilae at magnitude 2.99 and 83 light-years distant. Lastly, the star at the end of the tail of the Eagle is Lambda Aquilae at magnitude 3.43, lying 125 light-years away.

Star chart with stars in black on white and constellation lines in green.
The stars of Aquila the Eagle. The larger the dot, the brighter the star. Image via IAU/ Sky and Telescope/ Wikimedia Commons (CC BY 3.0).

Globular clusters

While there are no Messier objects in Aquila, there is still a lot to see, especially if you have a big enough telescope. For example, two globular clusters lie in Aquila: NGC 6749 and NGC 6760.

The two globular clusters are in the vicinity of Delta Aquilae. NGC 6760 shines at magnitude 9.1. Then, about 2 degrees farther away is NGC 6749 at magnitude 12.

In addition, several open clusters lie in Aquila, but most of them are faint. With this in mind, the best one to observe is NGC 6755, a 7.5-magnitude grouping found near the star marking the back of the Eagle. Another good open cluster to try for is NGC 6709, which, at magnitude 6.7, appears in binoculars. NGC 6709 is fairly near Zeta Aquilae, the upper wing of the Eagle. Between these two clusters is yet another cluster, NGC 6738. This sparse cluster is 8th magnitude.

Also, a lot of observers who come to Aquila use it to starhop to a cluster just over the border of the constellation Scutum the Shield. The Wild Duck Cluster, M11, shines at magnitude 6.3, making it brighter than any of the clusters in Aquila. Here’s how to find it.

Antique colored etching of a flying eagle near a fish and an archer, all scattered with stars.
Altair in Aquila the Eagle, with 2 smaller constellations nearby. Image via Wikipedia.

Nebulae of Aquila

A number of nebulae lie along the line that marks the body of the Eagle, but only one is bright enough to reach even 10th magnitude. NGC 6790 lies a little less than 2 degrees from the star that marks the back of the Eagle in the direction of its tail.

Good luck tracking down these tough-to-spot, faint objects in Aquila the Eagle. Or, you can always just scan the area in binoculars and see what materializes.

Photo of the starlit band of the Milky Way, with outlines for Scutum, Aquila the Eagle and Lyra.
View at EarthSky Community Photos. | Cecille Kennedy caught this image from the central Oregon coast. Notice how Aquila the Eagle soars along the Milky Way. Thank you, Cecille!

Bottom line: Aquila the Eagle is home to the bright star Altair, which forms one corner of the Summer Triangle. And you can see this constellation at its best in northern late summer or early fall evenings.

The post Aquila the Eagle soars along the Milky Way first appeared on EarthSky.



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How to watch a solar eclipse safely: tips here

Group of 7 people, adults and children, sit at a picnic table, wearing eclipse glasses and looking up.
Raúl Cortés – a co-author of EarthSky’s daily sun post – is the one on the top right in this photo. He lives in Mexico. But he and his family traveled to Corpus Christi, Texas, to place themselves in the path of the annular eclipse on October 14, 2023. Thank you, Raúl! Read tips below on how to safely watch a solar eclipse.

You learned long ago never to look directly at the sun. Gazing sunward without eye protection can permanently damage your eyes. But there are a variety of ways you can safely view the August 12, 2026, total solar eclipse.

You deserve a daily dose of good news. For the latest in science and the night sky, click here to subscribe to our free daily newsletter.

Here’s what NOT to do

First, let’s cover what you shouldn’t do to look at the sun. Whatever you do, never look at the sun directly without a safe filter in place to protect your eyes.

Besides your unprotected eyeballs, here are some other things you should not use: Do NOT use sunglasses, polaroid filters, smoked glass, exposed color film, X-ray film or photographic neutral density filters.

A group watching the eclipsed sun, a man in the foreground aiming a filtered telescope toward it.
Fred Espenak created this self-portrait during a 2006 total solar eclipse. He’s using a small telescope equipped with a solar filter for observing the sun safely. Thank you, Fred! Used with permission. Read the ways to watch a solar eclipse – and the sun – safely, below.

DO use these techniques for observing the sun safely

Safe commercial solar filters for a telescope. If you have a telescope, you’ll need a safe solar filter on the sky end of it in order to search for sunspots or watch a solar eclipse safely. Do not use a filter on the eyepiece end of your telescope. There’s too much to say about solar filters to include in this article, so we refer you to Fred Espenak’s article on safe solar filters. If you don’t have a ‘scope, you still have plenty of options, such as …

Creating a pinhole camera. If you make a DIY easy pinhole projector, you can shine the sun’s image onto a flat surface and give your friends and family a cool experience too.

Use handy things around the house. You can use a colander, a slotted spoon or even criss-cross your fingers and let the sun shine through them to see dozens of little eclipsed suns on the ground.

Shadow on a wooden deck of a hand holding a colander and many small bright crescents projected onto deck.
Use a colander as an easy pinhole projector to safely view a solar eclipse. Image via Marcy Curran.

Check out the ground below trees

The little pinholes in leaves on trees are a wonderful pinhole projector.

Small boy in dark T-shirt and shorts standing on a deck, looking up through solar binoculars.
This young astronomer in Austin, Texas, is using solar binoculars, especially designed for watching eclipses and tracking sunspots. See the crescent suns at his feet? Those are projected images of the eclipsed sun. Image via EarthSky.

But wait, there’s more …

A commercial pinhole projector. There are several versions of this handy and unique device to safely project an image of the sun. The Sunspotter projects an enlarged image of the sun onto a piece of paper, and even shows all but the smallest sunspots. It’s easy to use, plus multiple people can safely watch the eclipse (or see sunspots) at the same time. Of course, for solar eclipses the advancing – and eventual retreating – of the moon’s shadow is easy to see and even photograph.

Wooden device with a semicircle base, a triangular insert projecting a picture of an eclipsed sun on white paper.
Commercial sun projection devices are available as well, such as this Sunspotter. They use lenses to project the sun on a piece of paper to safely watch solar eclipses and to view sunspots. Image via Marcy Curran.

Commercial solar eclipse glasses. You might find these online or at a local nature center or museum. Solar eclipse glasses – or eclipse viewers – are super easy to use, and they’re sort of cool-looking.

Watch a solar eclipse: Closeup of smiling young woman's sunlit face. She has on cardboard glasses with black lenses.
Certified eclipse glasses are a safe alternative for viewing.

Watch a solar eclipse with others

Local viewing at an astronomy club, park or nature center. We highly recommend this route for any kind of eclipse, any daytime solar viewing or any nighttime astronomical event. If you watch among other amateur astronomers and casual sky gazers, you’ll have fun, learn about astronomy and get a great view of the objects and events going on in the sky.

The NASA Night Sky Network has a list of local astronomy clubs in the U.S. Here’s a search page from Go-astronomy.com which includes worldwide clubs. And here are astronomy clubs and societies affiliated with the Astronomical League, one of the most established confederations of amateur astronomers in the U.S.

Bottom line: Some tips for observing the sun safely during a solar eclipse here.

Read about the August 12, 2026, total solar eclipse

The post How to watch a solar eclipse safely: tips here first appeared on EarthSky.



from EarthSky https://ift.tt/kiuES1m
Group of 7 people, adults and children, sit at a picnic table, wearing eclipse glasses and looking up.
Raúl Cortés – a co-author of EarthSky’s daily sun post – is the one on the top right in this photo. He lives in Mexico. But he and his family traveled to Corpus Christi, Texas, to place themselves in the path of the annular eclipse on October 14, 2023. Thank you, Raúl! Read tips below on how to safely watch a solar eclipse.

You learned long ago never to look directly at the sun. Gazing sunward without eye protection can permanently damage your eyes. But there are a variety of ways you can safely view the August 12, 2026, total solar eclipse.

You deserve a daily dose of good news. For the latest in science and the night sky, click here to subscribe to our free daily newsletter.

Here’s what NOT to do

First, let’s cover what you shouldn’t do to look at the sun. Whatever you do, never look at the sun directly without a safe filter in place to protect your eyes.

Besides your unprotected eyeballs, here are some other things you should not use: Do NOT use sunglasses, polaroid filters, smoked glass, exposed color film, X-ray film or photographic neutral density filters.

A group watching the eclipsed sun, a man in the foreground aiming a filtered telescope toward it.
Fred Espenak created this self-portrait during a 2006 total solar eclipse. He’s using a small telescope equipped with a solar filter for observing the sun safely. Thank you, Fred! Used with permission. Read the ways to watch a solar eclipse – and the sun – safely, below.

DO use these techniques for observing the sun safely

Safe commercial solar filters for a telescope. If you have a telescope, you’ll need a safe solar filter on the sky end of it in order to search for sunspots or watch a solar eclipse safely. Do not use a filter on the eyepiece end of your telescope. There’s too much to say about solar filters to include in this article, so we refer you to Fred Espenak’s article on safe solar filters. If you don’t have a ‘scope, you still have plenty of options, such as …

Creating a pinhole camera. If you make a DIY easy pinhole projector, you can shine the sun’s image onto a flat surface and give your friends and family a cool experience too.

Use handy things around the house. You can use a colander, a slotted spoon or even criss-cross your fingers and let the sun shine through them to see dozens of little eclipsed suns on the ground.

Shadow on a wooden deck of a hand holding a colander and many small bright crescents projected onto deck.
Use a colander as an easy pinhole projector to safely view a solar eclipse. Image via Marcy Curran.

Check out the ground below trees

The little pinholes in leaves on trees are a wonderful pinhole projector.

Small boy in dark T-shirt and shorts standing on a deck, looking up through solar binoculars.
This young astronomer in Austin, Texas, is using solar binoculars, especially designed for watching eclipses and tracking sunspots. See the crescent suns at his feet? Those are projected images of the eclipsed sun. Image via EarthSky.

But wait, there’s more …

A commercial pinhole projector. There are several versions of this handy and unique device to safely project an image of the sun. The Sunspotter projects an enlarged image of the sun onto a piece of paper, and even shows all but the smallest sunspots. It’s easy to use, plus multiple people can safely watch the eclipse (or see sunspots) at the same time. Of course, for solar eclipses the advancing – and eventual retreating – of the moon’s shadow is easy to see and even photograph.

Wooden device with a semicircle base, a triangular insert projecting a picture of an eclipsed sun on white paper.
Commercial sun projection devices are available as well, such as this Sunspotter. They use lenses to project the sun on a piece of paper to safely watch solar eclipses and to view sunspots. Image via Marcy Curran.

Commercial solar eclipse glasses. You might find these online or at a local nature center or museum. Solar eclipse glasses – or eclipse viewers – are super easy to use, and they’re sort of cool-looking.

Watch a solar eclipse: Closeup of smiling young woman's sunlit face. She has on cardboard glasses with black lenses.
Certified eclipse glasses are a safe alternative for viewing.

Watch a solar eclipse with others

Local viewing at an astronomy club, park or nature center. We highly recommend this route for any kind of eclipse, any daytime solar viewing or any nighttime astronomical event. If you watch among other amateur astronomers and casual sky gazers, you’ll have fun, learn about astronomy and get a great view of the objects and events going on in the sky.

The NASA Night Sky Network has a list of local astronomy clubs in the U.S. Here’s a search page from Go-astronomy.com which includes worldwide clubs. And here are astronomy clubs and societies affiliated with the Astronomical League, one of the most established confederations of amateur astronomers in the U.S.

Bottom line: Some tips for observing the sun safely during a solar eclipse here.

Read about the August 12, 2026, total solar eclipse

The post How to watch a solar eclipse safely: tips here first appeared on EarthSky.



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Luddites Is A Popular Technophobe Insult - Here's Who They Were

Luddites Is A Popular Technophobe Insult - Here's Who They Were

American filmmaker George Lucas is one of the latest to indicate he’s open to AI in the movie industry.

In a recent interview, the director said resistance to the technology was “very much like sitting here saying: ‘Well, I believe the horse and the buggy is really where it’s at. These cars, they break down, they need gas, there’s all kinds of problems with them and pretty soon they’ll be making them into tanks, and then they’ll be killing people. It’s terrible.’”

The Guardian story was headlined: “George Lucas likens AI sceptics to luddites clinging to horses and carts.”

“Luddites” have sometimes stood in for enemies of progress: those destined to be swept aside in the forward march of history.

Drawing of a man with his hand on another man's shoulder, while a third bystander holds his hat between his hands and looks down.
Image from ‘Through the Fray: a tale of the Luddite Riots, etc.,’ by George Alfred Henty, published in 1897. (British Library/Flickr)

The label of “neo-Luddism” or “digital Luddite” is also being reclaimed by people concerned about labour conditions, society and democracy in an era of AI expansion twinned with personal profit.

But who exactly were the Luddites? They were a collective reaction to the traumas of the Industrial Revolution, in early industrial England.

Their legacy has been profound, as suggested by both negative and positive polemics related to them in intellectual and cultural commentary, art and literature and popular histories produced as digital technology continues to grow.

When trade unions were illegal

As the new political economy, fueled by transatlantic slavery and colonial extraction, began to transform work practices in England and introduce new forms of mechanization, skilled artisans and weavers resisted. They sought to protect their livelihoods, their ways of life and their communities.

Trade unions were illegal and the workers did not have political representation. Co-operative societies did not yet exist and state welfare was a distant dream. The only alternative to acquiescence was what historian Eric Hobsbawm memorably called “collective bargaining by riot.”

Food riots, destroying machinery or setting fire to factories were in-your-face ways to get employers and local authorities to pay attention to their legitimate grievances.

When the English cartoonist Charles Williams depicted a veterinarian and a blacksmith violently attacking dandies on bicycles for undermining traditional horse-drawn transportation in 1819, the blacksmith’s smashing with a mallet was a clear reference to the spasm of machine-wrecking earlier in the decade.

Williams’s caricature came within a few years of the mass outbreak in Britain when the terms Luddism and Luddite became commonplace.


Cartoon by Charles Williams showing a veterinary surgeon and a blacksmith attacking dandies on bicycles representing the anti-bicycle movement. (Wikimedia), CC BY

Famous episodes of Luddism

Historians agree that the most famous episode of Luddism began in 1811 in Nottinghamshire in the English Midlands.

A group of stocking weavers formed a secret organization, purportedly led by a certain Ned Ludd, a fictitious figure also styled as Captain, General or King Ludd.


‘Leader of the Luddites’ hand-coloured etching from 1812. (British Museum)

In the context of widespread economic misery caused by the war against Napoleon, the weavers blamed new, wide-frame knitting machines for stealing their jobs, reducing their earnings and making a bad situation worse. In targeted attacks, they smashed more than 1,000 of the stocking frames, and the property destruction then spread to the textile weaving and spinning districts of Lancashire and Yorkshire.

Fearing the revolutionary potential of this wave of violence — and that English plebeians might follow the French example and overthrow the old regime — the government cracked down hard. It sent in 12,000 troops to quell the riots, and members of Parliament voted overwhelmingly to make frame-breaking a hanging offence.

The ruling classes managed to restore order, despite sporadic outbreaks until 1816, punctuating their clampdown with exemplary hangings and sentences of transportation to Australia. Their determination to prevent revolution, protect property and enable unfettered economic expansion was patently clear.


Destruction of property spread to the textile weaving and spinning districts of Lancashire and Yorkshire. (Wellcome Collection)

So do the Luddites deserve such a bad rap? As a historian who has examined industrial-era English history, along with many others, I say: absolutely not.

The Luddites were not blindly lashing out but sending a message; to some extent at least, that message was heard. Along with the political radicals and the labour campaigners over the course of the 19th century, they took part in a prolonged struggle waged for rights, dignity and justice. That struggle partially succeeded, forcing the ruling classes to compromise rather than continuing to rely on brute force.

As historian E.P. Thompson famously put it in his book The Making of the English Working Class, the Luddites need to be rescued “from the enormous condescension of posterity.”

Luddites in verse, literature

 


Byron lamented how ‘absolute want’ had ‘unparalleled distress’ had provoked riots. (Wellcome Collection), CC BY

One of the few aristocrats to express sympathy for the Luddites was the poet Lord Byron. In his maiden speech in the House of Lords, Byron lamented that “absolute want” and “unparalleled distress” had provoked the riots and, rather than compassion or an attempt to remedy wrongs, all the government could propose was “dragoons and executioners.”

A few months later, he penned a bitingly satirical poem in a London newspaper with a similar message:

“Some folks for certain have thought it was shocking,

When Famine appeals, and when Poverty groans,

That life should be valued at less than a stocking,

And breaking of frames lead to breaking of bones.”

Fellow poet Percy Bysshe Shelley reacted with similar rage. His 1813 poem Queen Mab, a paean to a utopian future, combined an attack on the state, organized religion and the soul-destroying capitalism of the new machine age.

Mary Wollstonecraft Shelley, wife of Percy and daughter of feminist philosopher Mary Wollstonecraft, was also inspired by Luddism in her writing of the 1818 novel Frankenstein. Victor Frankenstein’s creation, the Monster, like Ned Ludd, only became violent and destructive when horrendously mistreated.

The message was clear: technological progress was not necessarily in itself evil, but if the outcome was a vicious zero-sum game of winners and losers, then industrial capitalism was deeply inhumane and resistance was inevitable.

These were just the earliest writers who reacted to the Luddites. Notable later novelists tilling the same furrow included Charlotte Brontë and Samuel Butler.

Brontë’s 1849 novel Shirley, set in the Yorkshire textile district in 1811-12, combined sympathy for the plight of the workers with a criticism of violence and a call for paternalism from the mill owners.

Butler’s 1872 novel Erewhon, the ultimate Luddite fantasy, featured a society that outlawed machines and destroyed inventions to prevent them from taking over and enslaving humanity.

Not blindly lashing out

The Luddites may have partly lost the battle in Regency England; the state and the propertied classes may have prevailed.

But it’s a mistake to see them as no more than victims crushed by industrialization.

Caricatures of the Luddites as history’s losers are simply false. We have not stopped talking about them ever since.

By Brian Lewis, Professor of History, McGill University. This article is republished from The Conversation under a Creative Commons license. Read the original article.

The Conversation

sb admin
Categories
Social Sciences


from ScienceBlogs - Where the world discusses science https://ift.tt/J0uBg8c
Luddites Is A Popular Technophobe Insult - Here's Who They Were

American filmmaker George Lucas is one of the latest to indicate he’s open to AI in the movie industry.

In a recent interview, the director said resistance to the technology was “very much like sitting here saying: ‘Well, I believe the horse and the buggy is really where it’s at. These cars, they break down, they need gas, there’s all kinds of problems with them and pretty soon they’ll be making them into tanks, and then they’ll be killing people. It’s terrible.’”

The Guardian story was headlined: “George Lucas likens AI sceptics to luddites clinging to horses and carts.”

“Luddites” have sometimes stood in for enemies of progress: those destined to be swept aside in the forward march of history.

Drawing of a man with his hand on another man's shoulder, while a third bystander holds his hat between his hands and looks down.
Image from ‘Through the Fray: a tale of the Luddite Riots, etc.,’ by George Alfred Henty, published in 1897. (British Library/Flickr)

The label of “neo-Luddism” or “digital Luddite” is also being reclaimed by people concerned about labour conditions, society and democracy in an era of AI expansion twinned with personal profit.

But who exactly were the Luddites? They were a collective reaction to the traumas of the Industrial Revolution, in early industrial England.

Their legacy has been profound, as suggested by both negative and positive polemics related to them in intellectual and cultural commentary, art and literature and popular histories produced as digital technology continues to grow.

When trade unions were illegal

As the new political economy, fueled by transatlantic slavery and colonial extraction, began to transform work practices in England and introduce new forms of mechanization, skilled artisans and weavers resisted. They sought to protect their livelihoods, their ways of life and their communities.

Trade unions were illegal and the workers did not have political representation. Co-operative societies did not yet exist and state welfare was a distant dream. The only alternative to acquiescence was what historian Eric Hobsbawm memorably called “collective bargaining by riot.”

Food riots, destroying machinery or setting fire to factories were in-your-face ways to get employers and local authorities to pay attention to their legitimate grievances.

When the English cartoonist Charles Williams depicted a veterinarian and a blacksmith violently attacking dandies on bicycles for undermining traditional horse-drawn transportation in 1819, the blacksmith’s smashing with a mallet was a clear reference to the spasm of machine-wrecking earlier in the decade.

Williams’s caricature came within a few years of the mass outbreak in Britain when the terms Luddism and Luddite became commonplace.


Cartoon by Charles Williams showing a veterinary surgeon and a blacksmith attacking dandies on bicycles representing the anti-bicycle movement. (Wikimedia), CC BY

Famous episodes of Luddism

Historians agree that the most famous episode of Luddism began in 1811 in Nottinghamshire in the English Midlands.

A group of stocking weavers formed a secret organization, purportedly led by a certain Ned Ludd, a fictitious figure also styled as Captain, General or King Ludd.


‘Leader of the Luddites’ hand-coloured etching from 1812. (British Museum)

In the context of widespread economic misery caused by the war against Napoleon, the weavers blamed new, wide-frame knitting machines for stealing their jobs, reducing their earnings and making a bad situation worse. In targeted attacks, they smashed more than 1,000 of the stocking frames, and the property destruction then spread to the textile weaving and spinning districts of Lancashire and Yorkshire.

Fearing the revolutionary potential of this wave of violence — and that English plebeians might follow the French example and overthrow the old regime — the government cracked down hard. It sent in 12,000 troops to quell the riots, and members of Parliament voted overwhelmingly to make frame-breaking a hanging offence.

The ruling classes managed to restore order, despite sporadic outbreaks until 1816, punctuating their clampdown with exemplary hangings and sentences of transportation to Australia. Their determination to prevent revolution, protect property and enable unfettered economic expansion was patently clear.


Destruction of property spread to the textile weaving and spinning districts of Lancashire and Yorkshire. (Wellcome Collection)

So do the Luddites deserve such a bad rap? As a historian who has examined industrial-era English history, along with many others, I say: absolutely not.

The Luddites were not blindly lashing out but sending a message; to some extent at least, that message was heard. Along with the political radicals and the labour campaigners over the course of the 19th century, they took part in a prolonged struggle waged for rights, dignity and justice. That struggle partially succeeded, forcing the ruling classes to compromise rather than continuing to rely on brute force.

As historian E.P. Thompson famously put it in his book The Making of the English Working Class, the Luddites need to be rescued “from the enormous condescension of posterity.”

Luddites in verse, literature

 


Byron lamented how ‘absolute want’ had ‘unparalleled distress’ had provoked riots. (Wellcome Collection), CC BY

One of the few aristocrats to express sympathy for the Luddites was the poet Lord Byron. In his maiden speech in the House of Lords, Byron lamented that “absolute want” and “unparalleled distress” had provoked the riots and, rather than compassion or an attempt to remedy wrongs, all the government could propose was “dragoons and executioners.”

A few months later, he penned a bitingly satirical poem in a London newspaper with a similar message:

“Some folks for certain have thought it was shocking,

When Famine appeals, and when Poverty groans,

That life should be valued at less than a stocking,

And breaking of frames lead to breaking of bones.”

Fellow poet Percy Bysshe Shelley reacted with similar rage. His 1813 poem Queen Mab, a paean to a utopian future, combined an attack on the state, organized religion and the soul-destroying capitalism of the new machine age.

Mary Wollstonecraft Shelley, wife of Percy and daughter of feminist philosopher Mary Wollstonecraft, was also inspired by Luddism in her writing of the 1818 novel Frankenstein. Victor Frankenstein’s creation, the Monster, like Ned Ludd, only became violent and destructive when horrendously mistreated.

The message was clear: technological progress was not necessarily in itself evil, but if the outcome was a vicious zero-sum game of winners and losers, then industrial capitalism was deeply inhumane and resistance was inevitable.

These were just the earliest writers who reacted to the Luddites. Notable later novelists tilling the same furrow included Charlotte Brontë and Samuel Butler.

Brontë’s 1849 novel Shirley, set in the Yorkshire textile district in 1811-12, combined sympathy for the plight of the workers with a criticism of violence and a call for paternalism from the mill owners.

Butler’s 1872 novel Erewhon, the ultimate Luddite fantasy, featured a society that outlawed machines and destroyed inventions to prevent them from taking over and enslaving humanity.

Not blindly lashing out

The Luddites may have partly lost the battle in Regency England; the state and the propertied classes may have prevailed.

But it’s a mistake to see them as no more than victims crushed by industrialization.

Caricatures of the Luddites as history’s losers are simply false. We have not stopped talking about them ever since.

By Brian Lewis, Professor of History, McGill University. This article is republished from The Conversation under a Creative Commons license. Read the original article.

The Conversation

sb admin
Categories
Social Sciences


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Were Neptune’s inner moons born from an ancient cataclysm?

Neptune's inner moons: Hazy-looking planet with rings and several small moons near it.
View larger. | This infrared image from the James Webb Space Telescope, taken on July 12, 2022, shows Neptune, its rings and some of its inner moons. A new study shows that Neptune’s inner moons might have formed through the destruction of a previous family of moons. Image via NASA/ ESA/ CSA/ STScI; Image Processing: Joseph DePasquale (STScI)/ Naomi Rowe-Gurney (NASA-GSFC).
  • How did Neptune’s inner moons form? Scientists have considered various possibilities.
  • A new hypothesis suggests that they formed from the remnants of a previous family of moons. Those moons would have been mostly obliterated when Neptune’s gravity captured Triton, the planet’s largest moon.
  • Two of the studied moons, surprisingly, have rich clay deposits. But the third moon has none. Why?

You deserve a daily dose of good news. For the latest in science and the night sky, subscribe to EarthSky’s free daily newsletter.

Neptune’s inner moons

Neptune has 16 known moons. NASA’s James Webb Space Telescope recently took a closer look at three of the innermost small moons – Larissa, Galatea and Proteus – and found something interesting; they have a unique composition among all the bodies in the solar system.

Having looked into this surprising finding, a team of researchers said on July 29, 2026, that these moons likely formed from the remnants of a former system of moons around Neptune. They believe these moons were destroyed when the planet’s current largest moon, Triton, was captured by Neptune billions of years ago.

Ryleigh Davis, a former Caltech graduate student, now at UC San Diego, is the lead author of a new paper about these moons. She said:

If Neptune once had a system of moons that looked something like what we see at Uranus today [a stable family of multiple moons of different sizes orbiting the planet], we expect it would’ve been completely destroyed by the process of Triton getting captured. This is exciting new evidence that something catastrophic happened at Neptune that completely destroyed its original satellites, and we’re getting to see the fingerprints left behind by that process.

Those former icy moons are all gone now, except maybe for Nereid. Scientists think it might be the sole survivor of that catastrophe.

Davis and her colleagues published their peer-reviewed findings in Science Advances on July 29, 2026.

Diagram showing a planet with rings in black and white, with 2 colored squares, 1 on either side, with text labels.
View larger. | Infrared view from the James Webb Space Telescope of the moon Larissa, and Neptune and its rings. Image via Davis et al. 2026; NASA/ ESA/ CSA JWST data/ Caltech.

Clays on Larissa, Galatea and in the rings

The researchers wanted to study Neptune’s inner moons more, to learn more about the planet’s history. There is still much that scientists don’t know about these small, distant worlds.

Astronomers had only recently obtained spectroscopy data for the moons, which tells scientists what kinds of molecules are present.

Surprisingly, they found phyllosilicates, or clays, on the moons, and in Neptune’s rings. It was an unexpected discovery, as Davis noted:

Phyllosilicates had never been detected anywhere in the outer solar system beyond Jupiter, so that was not on our list of things to look for. We were shocked to find the observed clays, which had to come from objects that were much, much bigger than Neptune’s small inner ring moons.

Webb found the signatures of magnesium-rich phyllosilicates (clays). Why was this surprising?

Diagram in 4 parts showing a blue planet with rings and moons, as the moons formed and changed.
View larger. | This diagram depicts how the current inner moons of Neptune formed. The capture of Triton by Neptune destroyed the previous family of moons. The current small moon then formed from their debris. Image via R. Davis/ Caltech (License: original content).

Where did the clays come from?

Clays require water to form. But no water ice was found on any of the moons or in the rings. And it’s way too cold for liquid water. So the moons and rings must have originated from some body or bodies that did have ice. Davis explained:

That’s really surprising because everything out in this part of the solar system is really icy. So, we’re fairly confident that they had to come from deep inside something that was big enough to generate enough heat that it melted its water ice. We think the most likely place would be an original system of icy moons, although it’s a bit of a mystery where the ice may have gone.

Scientist Mike Brown at Caltech added:

It took diligent detective work from Ryleigh before we understood what we were seeing. Sometimes in science you are trying to find evidence to evaluate a specific hypothesis, and, sometimes, something that you had not been thinking about just hits you in the face.

Fuzzy, oblong gray object on black background.
Nereid is the 3rd-largest moon of Neptune. It might be the only original inner moon left that survived the cataclysm caused by Triton. This is still the best image of the moon, captured by Voyager 2 on August 24, 1989. Image via NASA/ Wikimedia Commons.

No clays for Proteus and an unknown mineral

There’s another twist, though. Proteus is the largest of the three small moons. And it doesn’t have the clays on it. Why? It might simply have originated from a part of the former debris where clays were absent. Or, perhaps there were clays originally, but heat destroyed them.

Plus, Webb identified a hydrated mineral that is on all three moons. But scientists don’t know what it is yet. It hasn’t even been seen elsewhere in the solar system. Davis said:

We see something that doesn’t really look like anything else we’ve identified in the solar system; it doesn’t match anything we have in our spectral libraries. We assume it’s some form of hydrated rock from the moons as well, but there’s still a lot of mystery.

This is reminiscent of another recent discovery. Scientists found a mineral that is present on the surfaces of both Pluto and Saturn’s moon Titan. But again, it’s never been seen before anywhere else, until now.

Smiling woman wearing a dark blue blazer and white shirt.
Ryleigh Davis at UC San Diego is the lead author of the new paper about Neptune’s inner moons. Image via GitHub.

A destroyed Kuiper Belt object?

The researchers consider the system of ancient moons to be the most likely scenario to explain the current inner moons of Neptune. But there is another possibility. A larger single object from the Kuiper Belt beyond Neptune, about the size of Pluto, might have passed too close to Neptune. Neptune’s immense gravity would then have shredded the object. Davis said:

Either way, what we’re seeing on these moons had to come from deep inside something much larger. That material is normally permanently buried—we can only infer what’s there. Here, a catastrophic event essentially turned these ancient moons inside out, and we get to see what was hidden inside.

But if Triton did play a role, then it would have had a big effect on how the current moons formed and their behavior. Davis noted:

If you bring Triton in, and you smash up your large moons, we think only 1 percent or so of that material stayed around in the system. But the actual behavior of that material might be really different if Triton is still there shaking things up for a long time. So, looking forward, understanding how that process actually proceeds would be interesting. From there, the question is: ‘Can we learn anything about how big the initial moons had to be to have formed and provided this material?’

Bottom line: A new study suggests that Neptune’s inner moons formed when Neptune captured its largest moon Triton, and a family of original small icy moons was destroyed.

Source: Neptune’s inner moons and rings are exposed icy body interiors

Via Caltech

Read more: Are Uranus and Neptune rock giants and not ice giants?

Read more: New moons! Uranus now has 28 and Neptune 16

The post Were Neptune’s inner moons born from an ancient cataclysm? first appeared on EarthSky.



from EarthSky https://ift.tt/0qQCXIe
Neptune's inner moons: Hazy-looking planet with rings and several small moons near it.
View larger. | This infrared image from the James Webb Space Telescope, taken on July 12, 2022, shows Neptune, its rings and some of its inner moons. A new study shows that Neptune’s inner moons might have formed through the destruction of a previous family of moons. Image via NASA/ ESA/ CSA/ STScI; Image Processing: Joseph DePasquale (STScI)/ Naomi Rowe-Gurney (NASA-GSFC).
  • How did Neptune’s inner moons form? Scientists have considered various possibilities.
  • A new hypothesis suggests that they formed from the remnants of a previous family of moons. Those moons would have been mostly obliterated when Neptune’s gravity captured Triton, the planet’s largest moon.
  • Two of the studied moons, surprisingly, have rich clay deposits. But the third moon has none. Why?

You deserve a daily dose of good news. For the latest in science and the night sky, subscribe to EarthSky’s free daily newsletter.

Neptune’s inner moons

Neptune has 16 known moons. NASA’s James Webb Space Telescope recently took a closer look at three of the innermost small moons – Larissa, Galatea and Proteus – and found something interesting; they have a unique composition among all the bodies in the solar system.

Having looked into this surprising finding, a team of researchers said on July 29, 2026, that these moons likely formed from the remnants of a former system of moons around Neptune. They believe these moons were destroyed when the planet’s current largest moon, Triton, was captured by Neptune billions of years ago.

Ryleigh Davis, a former Caltech graduate student, now at UC San Diego, is the lead author of a new paper about these moons. She said:

If Neptune once had a system of moons that looked something like what we see at Uranus today [a stable family of multiple moons of different sizes orbiting the planet], we expect it would’ve been completely destroyed by the process of Triton getting captured. This is exciting new evidence that something catastrophic happened at Neptune that completely destroyed its original satellites, and we’re getting to see the fingerprints left behind by that process.

Those former icy moons are all gone now, except maybe for Nereid. Scientists think it might be the sole survivor of that catastrophe.

Davis and her colleagues published their peer-reviewed findings in Science Advances on July 29, 2026.

Diagram showing a planet with rings in black and white, with 2 colored squares, 1 on either side, with text labels.
View larger. | Infrared view from the James Webb Space Telescope of the moon Larissa, and Neptune and its rings. Image via Davis et al. 2026; NASA/ ESA/ CSA JWST data/ Caltech.

Clays on Larissa, Galatea and in the rings

The researchers wanted to study Neptune’s inner moons more, to learn more about the planet’s history. There is still much that scientists don’t know about these small, distant worlds.

Astronomers had only recently obtained spectroscopy data for the moons, which tells scientists what kinds of molecules are present.

Surprisingly, they found phyllosilicates, or clays, on the moons, and in Neptune’s rings. It was an unexpected discovery, as Davis noted:

Phyllosilicates had never been detected anywhere in the outer solar system beyond Jupiter, so that was not on our list of things to look for. We were shocked to find the observed clays, which had to come from objects that were much, much bigger than Neptune’s small inner ring moons.

Webb found the signatures of magnesium-rich phyllosilicates (clays). Why was this surprising?

Diagram in 4 parts showing a blue planet with rings and moons, as the moons formed and changed.
View larger. | This diagram depicts how the current inner moons of Neptune formed. The capture of Triton by Neptune destroyed the previous family of moons. The current small moon then formed from their debris. Image via R. Davis/ Caltech (License: original content).

Where did the clays come from?

Clays require water to form. But no water ice was found on any of the moons or in the rings. And it’s way too cold for liquid water. So the moons and rings must have originated from some body or bodies that did have ice. Davis explained:

That’s really surprising because everything out in this part of the solar system is really icy. So, we’re fairly confident that they had to come from deep inside something that was big enough to generate enough heat that it melted its water ice. We think the most likely place would be an original system of icy moons, although it’s a bit of a mystery where the ice may have gone.

Scientist Mike Brown at Caltech added:

It took diligent detective work from Ryleigh before we understood what we were seeing. Sometimes in science you are trying to find evidence to evaluate a specific hypothesis, and, sometimes, something that you had not been thinking about just hits you in the face.

Fuzzy, oblong gray object on black background.
Nereid is the 3rd-largest moon of Neptune. It might be the only original inner moon left that survived the cataclysm caused by Triton. This is still the best image of the moon, captured by Voyager 2 on August 24, 1989. Image via NASA/ Wikimedia Commons.

No clays for Proteus and an unknown mineral

There’s another twist, though. Proteus is the largest of the three small moons. And it doesn’t have the clays on it. Why? It might simply have originated from a part of the former debris where clays were absent. Or, perhaps there were clays originally, but heat destroyed them.

Plus, Webb identified a hydrated mineral that is on all three moons. But scientists don’t know what it is yet. It hasn’t even been seen elsewhere in the solar system. Davis said:

We see something that doesn’t really look like anything else we’ve identified in the solar system; it doesn’t match anything we have in our spectral libraries. We assume it’s some form of hydrated rock from the moons as well, but there’s still a lot of mystery.

This is reminiscent of another recent discovery. Scientists found a mineral that is present on the surfaces of both Pluto and Saturn’s moon Titan. But again, it’s never been seen before anywhere else, until now.

Smiling woman wearing a dark blue blazer and white shirt.
Ryleigh Davis at UC San Diego is the lead author of the new paper about Neptune’s inner moons. Image via GitHub.

A destroyed Kuiper Belt object?

The researchers consider the system of ancient moons to be the most likely scenario to explain the current inner moons of Neptune. But there is another possibility. A larger single object from the Kuiper Belt beyond Neptune, about the size of Pluto, might have passed too close to Neptune. Neptune’s immense gravity would then have shredded the object. Davis said:

Either way, what we’re seeing on these moons had to come from deep inside something much larger. That material is normally permanently buried—we can only infer what’s there. Here, a catastrophic event essentially turned these ancient moons inside out, and we get to see what was hidden inside.

But if Triton did play a role, then it would have had a big effect on how the current moons formed and their behavior. Davis noted:

If you bring Triton in, and you smash up your large moons, we think only 1 percent or so of that material stayed around in the system. But the actual behavior of that material might be really different if Triton is still there shaking things up for a long time. So, looking forward, understanding how that process actually proceeds would be interesting. From there, the question is: ‘Can we learn anything about how big the initial moons had to be to have formed and provided this material?’

Bottom line: A new study suggests that Neptune’s inner moons formed when Neptune captured its largest moon Triton, and a family of original small icy moons was destroyed.

Source: Neptune’s inner moons and rings are exposed icy body interiors

Via Caltech

Read more: Are Uranus and Neptune rock giants and not ice giants?

Read more: New moons! Uranus now has 28 and Neptune 16

The post Were Neptune’s inner moons born from an ancient cataclysm? first appeared on EarthSky.



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