R Aquarii: A dynamic duo with geyser-like eruptions

Hubble captured a colorful close-up of R Aquarii, a bright binary star surrounded by a large glowing nebula. R Aquarii is in the center (large white spot) and is surrounded by a circular glow with X-shaped diffraction spikes. The nebula surrounds the star in long, arcing shapes made of thin, multicolored filaments. Image via NASA/ ESA/ Matthias Stute/ Margarita Karovska/ Davide De Martin (ESA/Hubble)/ Mahdi Zamani (ESA/Hubble).

NASA published this original story on October 16, 2024. Edits by EarthSky.

• R Aquarii is a special pair of stars, called a binary star, located 700 light-years from Earth.
• One star is a red giant, which is very big, and the other is a small, white dwarf star.
• The stars have explosive eruptions, and the Hubble Space Telescope has captured amazing pictures of glowing gas filaments around them.

Hubble captures violent eruptions on R Aquarii

The Hubble Space Telescope has captured close-up images of R Aquarii, a binary star system 700 light-years away.

R Aquarii experiences violent eruptions that produce glowing gas filaments in a spiral pattern. The system consists of a red giant star and a white dwarf. The red giant is over 400 times larger than the sun.

When the white dwarf siphons hydrogen from the red giant, it causes explosive nuclear fusion on its surface. Hubble has been observing R Aquarii since 1990. NASA recently created a timelapse video showing its dynamic behavior from 2014 to 2023.

Meet R Aquarri

A binary star system called R Aquarii – located approximately 700 light-years away – undergoes violent eruptions that blast out huge filaments of glowing gas. The system demonstrates how the universe redistributes the products of nuclear energy that form deep inside stars and blast them back out into space. The twisted stellar outflows make an interesting shape on our sky’s dome. Some say the region looks like a lawn sprinkler gone berserk. Others see it as a great cosmic bird in flight.

R Aquarii belongs to a class of double stars called symbiotic binary stars. The primary star is an aging red giant and its companion is a compact burned-out star known as a white dwarf. Astronomers classify the red giant primary star as a Mira variable. And it’s over 400 times larger than our sun. The monster star pulsates, changes temperature, and varies in brightness by a factor of 750 times over a roughly 390-day period. At its peak the star is blinding at nearly 5,000 times our sun’s brightness.

Outbursts cause geyser-like filaments

When the white dwarf star swings closest to the red giant along its 44-year orbital period, it gravitationally siphons off hydrogen gas. This material accumulates on the dwarf star’s surface until it undergoes spontaneous nuclear fusion, making that surface explode like a gigantic hydrogen bomb. After the outburst, the fueling cycle begins again.

This outburst ejects geyser-like filaments shooting out from the core, forming weird loops and trails as the plasma emerges in streamers. The force of the explosion twists the plasma and channels it upward and outward from strong magnetic fields. The outflow appears to bend back on itself into a spiral pattern. The plasma is shooting into space over 1 million miles per hour. That’s fast enough to travel from Earth to the moon in 15 minutes! Radiation from the stellar duo energize the filaments and they glow in visible light.

Hubble shows evolution of the binary star

Hubble first observed the star in 1990. R Aquarii was resolved into two very bright stars separated by about 1.6 billion miles. The ESA/Hubble team released a time-lapse of R Aquarii’s dynamic behavior, from observations spanning from 2014 to 2023. Additionally, across the five images, it’s easy to see the rapid and dramatic evolution of the binary star and its surrounding nebula. Plus the binary star dims and brightens due to strong pulsations in the red giant star.

By the way, the scale of the event is extraordinary even in astronomical terms. Space-blasted material can be traced out to at least 248 billion miles from the stars, or 24 times our solar system’s diameter.

Bottom line: Hubble captured images of R Aquarii, a binary star system 700 light-years away. It has violent eruptions that produce spiral filaments of glowing gas.

Via Hubble site

The post R Aquarii: A dynamic duo with geyser-like eruptions first appeared on EarthSky.

from EarthSky https://ift.tt/yVxk01Q

Hubble captured a colorful close-up of R Aquarii, a bright binary star surrounded by a large glowing nebula. R Aquarii is in the center (large white spot) and is surrounded by a circular glow with X-shaped diffraction spikes. The nebula surrounds the star in long, arcing shapes made of thin, multicolored filaments. Image via NASA/ ESA/ Matthias Stute/ Margarita Karovska/ Davide De Martin (ESA/Hubble)/ Mahdi Zamani (ESA/Hubble).

NASA published this original story on October 16, 2024. Edits by EarthSky.

• R Aquarii is a special pair of stars, called a binary star, located 700 light-years from Earth.
• One star is a red giant, which is very big, and the other is a small, white dwarf star.
• The stars have explosive eruptions, and the Hubble Space Telescope has captured amazing pictures of glowing gas filaments around them.

Hubble captures violent eruptions on R Aquarii

The Hubble Space Telescope has captured close-up images of R Aquarii, a binary star system 700 light-years away.

R Aquarii experiences violent eruptions that produce glowing gas filaments in a spiral pattern. The system consists of a red giant star and a white dwarf. The red giant is over 400 times larger than the sun.

When the white dwarf siphons hydrogen from the red giant, it causes explosive nuclear fusion on its surface. Hubble has been observing R Aquarii since 1990. NASA recently created a timelapse video showing its dynamic behavior from 2014 to 2023.

Meet R Aquarri

A binary star system called R Aquarii – located approximately 700 light-years away – undergoes violent eruptions that blast out huge filaments of glowing gas. The system demonstrates how the universe redistributes the products of nuclear energy that form deep inside stars and blast them back out into space. The twisted stellar outflows make an interesting shape on our sky’s dome. Some say the region looks like a lawn sprinkler gone berserk. Others see it as a great cosmic bird in flight.

R Aquarii belongs to a class of double stars called symbiotic binary stars. The primary star is an aging red giant and its companion is a compact burned-out star known as a white dwarf. Astronomers classify the red giant primary star as a Mira variable. And it’s over 400 times larger than our sun. The monster star pulsates, changes temperature, and varies in brightness by a factor of 750 times over a roughly 390-day period. At its peak the star is blinding at nearly 5,000 times our sun’s brightness.

Outbursts cause geyser-like filaments

When the white dwarf star swings closest to the red giant along its 44-year orbital period, it gravitationally siphons off hydrogen gas. This material accumulates on the dwarf star’s surface until it undergoes spontaneous nuclear fusion, making that surface explode like a gigantic hydrogen bomb. After the outburst, the fueling cycle begins again.

This outburst ejects geyser-like filaments shooting out from the core, forming weird loops and trails as the plasma emerges in streamers. The force of the explosion twists the plasma and channels it upward and outward from strong magnetic fields. The outflow appears to bend back on itself into a spiral pattern. The plasma is shooting into space over 1 million miles per hour. That’s fast enough to travel from Earth to the moon in 15 minutes! Radiation from the stellar duo energize the filaments and they glow in visible light.

Hubble shows evolution of the binary star

Hubble first observed the star in 1990. R Aquarii was resolved into two very bright stars separated by about 1.6 billion miles. The ESA/Hubble team released a time-lapse of R Aquarii’s dynamic behavior, from observations spanning from 2014 to 2023. Additionally, across the five images, it’s easy to see the rapid and dramatic evolution of the binary star and its surrounding nebula. Plus the binary star dims and brightens due to strong pulsations in the red giant star.

By the way, the scale of the event is extraordinary even in astronomical terms. Space-blasted material can be traced out to at least 248 billion miles from the stars, or 24 times our solar system’s diameter.

Bottom line: Hubble captured images of R Aquarii, a binary star system 700 light-years away. It has violent eruptions that produce spiral filaments of glowing gas.

Via Hubble site

The post R Aquarii: A dynamic duo with geyser-like eruptions first appeared on EarthSky.

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First 1% of new cosmic atlas reveals millions of galaxies

• With the Euclid mission, scientists hope to gain insight about our expanding universe by learning more about dark energy.
• The mission is mapping the sky in 3D so that we can better understand its structure and composition.
• The first 1% of this cosmic atlas is now available, and it has captured millions of galaxies in incredible detail.

NASA/JPL published this original story on October 15, 2024. Edits by EarthSky.

Euclid mission begins its cosmic atlas

In 2023, the Euclid spacecraft launched from Florida on a mission to learn why the universe is expanding at an accelerating rate. To do so, the wide-angle space telescope is creating the most extensive 3D map of the universe yet. On October 15, 2024, the Euclid team released its first portion – just 1% – of the cosmic atlas, which covers more than 500 times the area of the full moon. The 208-gigapixel mosaic gives us a sneak peak of what’s to come in Euclid’s six-year mission.

The Euclid team released the new images at the International Astronautical Congress in Milan on October 15.

This photo mosaic is the beginning of a new cosmic atlas from ESA’s Euclid space telescope. It contains 260 observations in visible and infrared light and covers 132 square degrees, or more than 500 times the area of the full moon. This is 1% of the wide survey that Euclid will capture during its 6-year mission. Image via ESA/ Euclid/ Euclid Consortium/ NASA, CEA Paris-Saclay, image processing by J.-C. Cuillandre, E. Bertin, G. Anselmi (CC BY-SA 3.0 IGO).

A deep view into space

The mosaic contains 260 observations in visible and infrared light made between March 25 and April 8 of this year. In just two weeks, Euclid covered 132 square degrees of the southern sky, or more than 500 times the area of the sky covered by a full moon.

The mosaic accounts for 1% of the wide survey Euclid will conduct over six years. During this survey, the telescope observes the shapes, distances and motions of billions of galaxies out to a distance of more than 10 billion light-years. By doing this, it will create the largest 3D cosmic map ever made.

This first piece of the map already contains around 100 million stars and galaxies. Some 14 million of these galaxies could be used by Euclid to study the hidden influence of dark energy on the universe.

Jason Rhodes is an observational cosmologist at NASA’s Jet Propulsion Laboratory in Southern California. He’s also the U.S. science lead for Euclid and principal investigator for NASA’s Euclid dark energy science team. Rhodes said:

We have already seen beautiful, high-resolution images of individual objects and groups of objects from Euclid. This new image finally gives us a taste of the enormity of the area of sky Euclid will cover, which will enable us to take detailed measurements of billions of galaxies.

A closer look at our universe

Even though this patch of space shows only 1% of Euclid’s total survey area, the spacecraft’s sensitive cameras captured an incredible number of objects in great detail. Enlarging the image by a factor of 600 reveals the intricate structure of a spiral galaxy in galaxy cluster Abell 3381, 470 million light-years away.

JPL’s Mike Seiffert is project scientist for the NASA contribution to Euclid. Seiffert said:

What really strikes me about these new images is the tremendous range in physical scale. The images capture detail from clusters of stars near an individual galaxy to some of the largest structures in the universe. We are beginning to see the first hints of what the full Euclid data will look like when it reaches the completion of the prime survey.

In the new mosaic, we can also see clouds of gas and dust located between the stars in our own galaxy. Sometimes called galactic cirrus because they look like cirrus clouds at Earth, Euclid’s visible-light camera can see these clouds because they reflect visible light from the Milky Way.

Zoom in for incredible detail

ESA’s Planck and Gaia missions previously captured this map of the entire sky. The area highlighted in yellow is the location of the newly released Euclid mosaic. Image via ESA/ Euclid/ Euclid Consortium/ NASA/ Gaia/ DPAC/ Planck Collaboration (CC BY-SA 3.0 IGO).

This section of the Euclid mosaic is zoomed in 36 times, revealing the core of galaxy cluster Abell 3381. It’s 470 million light-years from Earth. The image, made using both visible and infrared light, shows galaxies of different shapes and sizes, including elliptical, spiral and dwarf galaxies. Image via ESA/ Euclid/ Euclid Consortium/ NASA, CEA Paris-Saclay, image processing by J.-C. Cuillandre, E. Bertin, G. Anselmi (CC BY-SA 3.0 IGO).

Here’s the same region as above (lower left portion), now zoomed in 150 times. Image via ESA/ Euclid/ Euclid Consortium/ NASA, CEA Paris-Saclay, image processing by J.-C. Cuillandre, E. Bertin, G. Anselmi (CC BY-SA 3.0 IGO).

And here’s a close-up on one of the spiral galaxies from Euclid. This section is zoomed in 600 times. Image via ESA/ Euclid/ Euclid Consortium/ NASA, CEA Paris-Saclay, image processing by J.-C. Cuillandre, E. Bertin, G. Anselmi (CC BY-SA 3.0 IGO).

More to come for the cosmic atlas

The mosaic released today is taste of what’s to come from Euclid. The mission plans to release 53 square degrees of the Euclid survey, including a preview of the Euclid Deep Field areas, in March 2025. The Euclid team will then release its first year of cosmology data in 2026.

NASA’s forthcoming Nancy Grace Roman mission will also study dark energy, in ways that are complementary to Euclid. Mission planners will use Euclid’s findings to inform Roman’s dark energy work. Scheduled to launch by May 2027, Roman will study a smaller section of sky than Euclid but will provide higher-resolution images of millions of galaxies. It will also peer deeper into the universe’s past, providing complementary information. In addition, Roman will survey nearby galaxies, find and investigate planets throughout our galaxy, study objects on the outskirts of our solar system and more.

Bottom line: The Euclid mission to survey the universe and help us understand the nature of dark energy and the expanding universe has just released the first 1% of its cosmic atlas.

Via NASA/JPL

The post First 1% of new cosmic atlas reveals millions of galaxies first appeared on EarthSky.

from EarthSky https://ift.tt/pqMh7wu

• With the Euclid mission, scientists hope to gain insight about our expanding universe by learning more about dark energy.
• The mission is mapping the sky in 3D so that we can better understand its structure and composition.
• The first 1% of this cosmic atlas is now available, and it has captured millions of galaxies in incredible detail.

NASA/JPL published this original story on October 15, 2024. Edits by EarthSky.

Euclid mission begins its cosmic atlas

In 2023, the Euclid spacecraft launched from Florida on a mission to learn why the universe is expanding at an accelerating rate. To do so, the wide-angle space telescope is creating the most extensive 3D map of the universe yet. On October 15, 2024, the Euclid team released its first portion – just 1% – of the cosmic atlas, which covers more than 500 times the area of the full moon. The 208-gigapixel mosaic gives us a sneak peak of what’s to come in Euclid’s six-year mission.

The Euclid team released the new images at the International Astronautical Congress in Milan on October 15.

This photo mosaic is the beginning of a new cosmic atlas from ESA’s Euclid space telescope. It contains 260 observations in visible and infrared light and covers 132 square degrees, or more than 500 times the area of the full moon. This is 1% of the wide survey that Euclid will capture during its 6-year mission. Image via ESA/ Euclid/ Euclid Consortium/ NASA, CEA Paris-Saclay, image processing by J.-C. Cuillandre, E. Bertin, G. Anselmi (CC BY-SA 3.0 IGO).

A deep view into space

The mosaic contains 260 observations in visible and infrared light made between March 25 and April 8 of this year. In just two weeks, Euclid covered 132 square degrees of the southern sky, or more than 500 times the area of the sky covered by a full moon.

The mosaic accounts for 1% of the wide survey Euclid will conduct over six years. During this survey, the telescope observes the shapes, distances and motions of billions of galaxies out to a distance of more than 10 billion light-years. By doing this, it will create the largest 3D cosmic map ever made.

This first piece of the map already contains around 100 million stars and galaxies. Some 14 million of these galaxies could be used by Euclid to study the hidden influence of dark energy on the universe.

Jason Rhodes is an observational cosmologist at NASA’s Jet Propulsion Laboratory in Southern California. He’s also the U.S. science lead for Euclid and principal investigator for NASA’s Euclid dark energy science team. Rhodes said:

We have already seen beautiful, high-resolution images of individual objects and groups of objects from Euclid. This new image finally gives us a taste of the enormity of the area of sky Euclid will cover, which will enable us to take detailed measurements of billions of galaxies.

A closer look at our universe

Even though this patch of space shows only 1% of Euclid’s total survey area, the spacecraft’s sensitive cameras captured an incredible number of objects in great detail. Enlarging the image by a factor of 600 reveals the intricate structure of a spiral galaxy in galaxy cluster Abell 3381, 470 million light-years away.

JPL’s Mike Seiffert is project scientist for the NASA contribution to Euclid. Seiffert said:

What really strikes me about these new images is the tremendous range in physical scale. The images capture detail from clusters of stars near an individual galaxy to some of the largest structures in the universe. We are beginning to see the first hints of what the full Euclid data will look like when it reaches the completion of the prime survey.

In the new mosaic, we can also see clouds of gas and dust located between the stars in our own galaxy. Sometimes called galactic cirrus because they look like cirrus clouds at Earth, Euclid’s visible-light camera can see these clouds because they reflect visible light from the Milky Way.

Zoom in for incredible detail

ESA’s Planck and Gaia missions previously captured this map of the entire sky. The area highlighted in yellow is the location of the newly released Euclid mosaic. Image via ESA/ Euclid/ Euclid Consortium/ NASA/ Gaia/ DPAC/ Planck Collaboration (CC BY-SA 3.0 IGO).

This section of the Euclid mosaic is zoomed in 36 times, revealing the core of galaxy cluster Abell 3381. It’s 470 million light-years from Earth. The image, made using both visible and infrared light, shows galaxies of different shapes and sizes, including elliptical, spiral and dwarf galaxies. Image via ESA/ Euclid/ Euclid Consortium/ NASA, CEA Paris-Saclay, image processing by J.-C. Cuillandre, E. Bertin, G. Anselmi (CC BY-SA 3.0 IGO).

Here’s the same region as above (lower left portion), now zoomed in 150 times. Image via ESA/ Euclid/ Euclid Consortium/ NASA, CEA Paris-Saclay, image processing by J.-C. Cuillandre, E. Bertin, G. Anselmi (CC BY-SA 3.0 IGO).

And here’s a close-up on one of the spiral galaxies from Euclid. This section is zoomed in 600 times. Image via ESA/ Euclid/ Euclid Consortium/ NASA, CEA Paris-Saclay, image processing by J.-C. Cuillandre, E. Bertin, G. Anselmi (CC BY-SA 3.0 IGO).

More to come for the cosmic atlas

The mosaic released today is taste of what’s to come from Euclid. The mission plans to release 53 square degrees of the Euclid survey, including a preview of the Euclid Deep Field areas, in March 2025. The Euclid team will then release its first year of cosmology data in 2026.

NASA’s forthcoming Nancy Grace Roman mission will also study dark energy, in ways that are complementary to Euclid. Mission planners will use Euclid’s findings to inform Roman’s dark energy work. Scheduled to launch by May 2027, Roman will study a smaller section of sky than Euclid but will provide higher-resolution images of millions of galaxies. It will also peer deeper into the universe’s past, providing complementary information. In addition, Roman will survey nearby galaxies, find and investigate planets throughout our galaxy, study objects on the outskirts of our solar system and more.

Bottom line: The Euclid mission to survey the universe and help us understand the nature of dark energy and the expanding universe has just released the first 1% of its cosmic atlas.

Via NASA/JPL

The post First 1% of new cosmic atlas reveals millions of galaxies first appeared on EarthSky.

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Meteors in moonlight: 6 tips for the Orionids

View at EarthSky Community Photos. | Joel Weatherly in Edmonton, Alberta, Canada, made this composite image under bright moonlight on August 12, 2022, and wrote: “Despite the blinding glare of a 97% waning gibbous moon, the Perseids delivered an enjoyable show. Numerous bright meteors raced across the night, including a couple that left behind persistent trains. This composite image features a few Perseid meteors.” Thank you, Joel! Read tips below for watching meteors in moonlight.

Moonlight will hinder the Orionid meteors in 2024

The best mornings to watch 2024’s Orionid meteor shower are October 20 and 21. But this year a fat waning gibbous moon, just a few days after the closest supermoon this year, will interfere. However, that doesn’t mean you can’t watch the Orionids in 2024. Here’s how to minimize the moon and optimize the 2024 Orionids.

1. Optimize your night sky for meteors

This should go without saying, but just a reminder to avoid city lights. A wide open area – a field or a lonely country road – is best if you’re serious about watching meteors. Visit EarthSky’s Best Places to Stargaze to find a dark location near you.

2. Find a moon shadow

On nights when the moon is full, or nearly full, you’ll notice that the moon casts shadows. When you’re out there watching the Orionids in 2024, don’t stand under a wide open sky. Instead, find somewhere that still provides you with a wide expanse of sky for meteor-viewing, but blocks out the moonlight. A plateau area with high-standing mountains to block out the moon would work just fine. If you can’t do that, find a hedgerow of trees bordering a wide open field somewhere (though obtain permission, if it’s private land). Or simply sit in the shadow of a barn or other building. Ensconced within a moon shadow, and far from the glow of city lights, the night all of a sudden darkens and can help you see more meteors. You can’t run from the moon, but you can sure hide from it.

3. Look carefully at the meteors

For most meteor showers, it’s all about the count. Meteor-watchers love to count how many meteors they see in, say, an hour. But when the moon is obscuring the view, you know your meteor count will be way down. So, instead of counting, look at each meteor you do see carefully. Notice the speed and colors, if any, of the meteors. Notice whether, as they streak through your sky, the meteors “pop” with brightness suddenly. Orionids tend to zip through the sky. Sometimes, an Orionid meteor can be exceptionally bright and break up into fragments.

Also, watch for meteor trains. A meteor train is a persistent glow in the air left by some meteors after they have faded from view. Trains are caused by luminous ionized matter left in the wake of this incoming space debris. Hard to see in the moonlight, but watch for them! And by the way, under a dark sky, roughly half of the Orionid meteors leave a persistent train. Watch for them!

4. Watch for earthgrazers and fireballs

Earthgrazers. Most meteor showers are best after midnight, and the Orionids are no exception. Their radiant point – in the constellation Orion – is highest in the sky around 2 a.m.. But you can also try watching for meteors in the late evening. And late evening is the best time to catch what’s called an earthgrazer: a bright, long-lasting meteor that travels horizontally across the sky. Earthgrazers are rare but memorable, if you’re lucky enough to spot one.

Fireballs. Even in bright moonlight, you might see an extremely bright meteor. Astronomers call them fireballs, and you have a shot at seeing one while watching a meteor shower. Unlike the meteors in annual showers – which start out no bigger than rice grains and are bits left behind by icy comets – a fireball starts as a larger, rockier object. So, fireballs aren’t necessarily part of the meteor shower. But if you happen to be outside watching a meteor shower, you might see one! If you do, you can report it here.

5. Make yourself comfortable

Bring along a blanket, some friends, a hot drink and a lawn chair. You’ll be more comfortable with a reclining lawn chair. If several of you are watching, take different parts of the sky. If you see one, shout “Meteor!” Let your eyes rove casually in all parts of the sky. Dress warmly; the nights can be cool or cold, even during the autumn and spring months. You’ll probably appreciate that blanket and warm drink in the wee hours of the morning.

Also, leave your cell phone in your pocket, and your laptops and tablets at home; even using the nighttime dark mode will ruin your night vision.

6. Enjoy nature

Not every meteor shower is a winner. Sometimes, you come away having seen only one meteor. But consider this. If that one meteor is a pretty one, or a colorful one, or it takes a slow path across a starry night sky, then it was worth it. Maybe you simply enjoyed being outside, bathing in the moonlight, smelling the night air and chatting with a friend. Heaven!

From a veteran sky photographer

Moonlit meteor, via veteran meteor photographer Eliot Herman in Tucson, Arizona. He caught this image on November 1, 2015, and wrote: “I have 2 rules for meteors: Avoid the moon, if possible, and if not, embrace the situation. Make the adjustments and accept that, while the photos probably won’t be epic, it’s possible to record the good ones. The moon isn’t so bad. Clouds are.”

Eliot Herman in Tucson also caught this image. He said this one – from early July 2017 – is one of the brightest meteors he caught in 2017, despite the moon. When we asked him for tips for shooting meteors in bright moonlight, he answered: “I shoot my images so that it is bright i.e. ISO 2500 at F5 for 15 sec in RAW (this is critical) at 8 mm fisheye. Using the RAW images in Photoshop, I adjust the white balance to look like the sky color, and then adjust saturation, gamma, exposure, and levels until the stars appear against a background that looks closer to reality. It’s not difficult to do this, takes just a few minutes to process one image. There are aspects like moonlight reflections that one has to live with. I do not mask or otherwise hide anything, although that can be done with in Photoshop. But I like my images to be real, so no subtractions. Meteors at +2 magnitude can easily be seen even in full moonlight. In dark skies, I shoot ISO 3200 F 3.5 for 15 seconds, and it is, of course, much better.” Thank you, Eliot!

Bottom line: A very bright waning gibbous moon that is up most of the night will do its best to drown out the 2024 Orionid meteor shower. Here are some tips for enjoying the moonlit Orionids in 2024.

The post Meteors in moonlight: 6 tips for the Orionids first appeared on EarthSky.

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View at EarthSky Community Photos. | Joel Weatherly in Edmonton, Alberta, Canada, made this composite image under bright moonlight on August 12, 2022, and wrote: “Despite the blinding glare of a 97% waning gibbous moon, the Perseids delivered an enjoyable show. Numerous bright meteors raced across the night, including a couple that left behind persistent trains. This composite image features a few Perseid meteors.” Thank you, Joel! Read tips below for watching meteors in moonlight.

Moonlight will hinder the Orionid meteors in 2024

The best mornings to watch 2024’s Orionid meteor shower are October 20 and 21. But this year a fat waning gibbous moon, just a few days after the closest supermoon this year, will interfere. However, that doesn’t mean you can’t watch the Orionids in 2024. Here’s how to minimize the moon and optimize the 2024 Orionids.

1. Optimize your night sky for meteors

This should go without saying, but just a reminder to avoid city lights. A wide open area – a field or a lonely country road – is best if you’re serious about watching meteors. Visit EarthSky’s Best Places to Stargaze to find a dark location near you.

2. Find a moon shadow

On nights when the moon is full, or nearly full, you’ll notice that the moon casts shadows. When you’re out there watching the Orionids in 2024, don’t stand under a wide open sky. Instead, find somewhere that still provides you with a wide expanse of sky for meteor-viewing, but blocks out the moonlight. A plateau area with high-standing mountains to block out the moon would work just fine. If you can’t do that, find a hedgerow of trees bordering a wide open field somewhere (though obtain permission, if it’s private land). Or simply sit in the shadow of a barn or other building. Ensconced within a moon shadow, and far from the glow of city lights, the night all of a sudden darkens and can help you see more meteors. You can’t run from the moon, but you can sure hide from it.

3. Look carefully at the meteors

For most meteor showers, it’s all about the count. Meteor-watchers love to count how many meteors they see in, say, an hour. But when the moon is obscuring the view, you know your meteor count will be way down. So, instead of counting, look at each meteor you do see carefully. Notice the speed and colors, if any, of the meteors. Notice whether, as they streak through your sky, the meteors “pop” with brightness suddenly. Orionids tend to zip through the sky. Sometimes, an Orionid meteor can be exceptionally bright and break up into fragments.

Also, watch for meteor trains. A meteor train is a persistent glow in the air left by some meteors after they have faded from view. Trains are caused by luminous ionized matter left in the wake of this incoming space debris. Hard to see in the moonlight, but watch for them! And by the way, under a dark sky, roughly half of the Orionid meteors leave a persistent train. Watch for them!

4. Watch for earthgrazers and fireballs

Earthgrazers. Most meteor showers are best after midnight, and the Orionids are no exception. Their radiant point – in the constellation Orion – is highest in the sky around 2 a.m.. But you can also try watching for meteors in the late evening. And late evening is the best time to catch what’s called an earthgrazer: a bright, long-lasting meteor that travels horizontally across the sky. Earthgrazers are rare but memorable, if you’re lucky enough to spot one.

Fireballs. Even in bright moonlight, you might see an extremely bright meteor. Astronomers call them fireballs, and you have a shot at seeing one while watching a meteor shower. Unlike the meteors in annual showers – which start out no bigger than rice grains and are bits left behind by icy comets – a fireball starts as a larger, rockier object. So, fireballs aren’t necessarily part of the meteor shower. But if you happen to be outside watching a meteor shower, you might see one! If you do, you can report it here.

5. Make yourself comfortable

Bring along a blanket, some friends, a hot drink and a lawn chair. You’ll be more comfortable with a reclining lawn chair. If several of you are watching, take different parts of the sky. If you see one, shout “Meteor!” Let your eyes rove casually in all parts of the sky. Dress warmly; the nights can be cool or cold, even during the autumn and spring months. You’ll probably appreciate that blanket and warm drink in the wee hours of the morning.

Also, leave your cell phone in your pocket, and your laptops and tablets at home; even using the nighttime dark mode will ruin your night vision.

6. Enjoy nature

Not every meteor shower is a winner. Sometimes, you come away having seen only one meteor. But consider this. If that one meteor is a pretty one, or a colorful one, or it takes a slow path across a starry night sky, then it was worth it. Maybe you simply enjoyed being outside, bathing in the moonlight, smelling the night air and chatting with a friend. Heaven!

From a veteran sky photographer

Moonlit meteor, via veteran meteor photographer Eliot Herman in Tucson, Arizona. He caught this image on November 1, 2015, and wrote: “I have 2 rules for meteors: Avoid the moon, if possible, and if not, embrace the situation. Make the adjustments and accept that, while the photos probably won’t be epic, it’s possible to record the good ones. The moon isn’t so bad. Clouds are.”

Eliot Herman in Tucson also caught this image. He said this one – from early July 2017 – is one of the brightest meteors he caught in 2017, despite the moon. When we asked him for tips for shooting meteors in bright moonlight, he answered: “I shoot my images so that it is bright i.e. ISO 2500 at F5 for 15 sec in RAW (this is critical) at 8 mm fisheye. Using the RAW images in Photoshop, I adjust the white balance to look like the sky color, and then adjust saturation, gamma, exposure, and levels until the stars appear against a background that looks closer to reality. It’s not difficult to do this, takes just a few minutes to process one image. There are aspects like moonlight reflections that one has to live with. I do not mask or otherwise hide anything, although that can be done with in Photoshop. But I like my images to be real, so no subtractions. Meteors at +2 magnitude can easily be seen even in full moonlight. In dark skies, I shoot ISO 3200 F 3.5 for 15 seconds, and it is, of course, much better.” Thank you, Eliot!

Bottom line: A very bright waning gibbous moon that is up most of the night will do its best to drown out the 2024 Orionid meteor shower. Here are some tips for enjoying the moonlit Orionids in 2024.

The post Meteors in moonlight: 6 tips for the Orionids first appeared on EarthSky.

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Fomalhaut is the Loneliest Star … but not in 2024

On October evenings in 2024, from the Northern Hemisphere, 2 objects can be seen sweeping across your southern sky. They are the Loneliest Star, Fomalhaut … not so lonely in 2024 because the golden planet Saturn is nearby. Fomalhaut and Saturn will be the brightest lights in that area of the sky. Watch for them! Chart via EarthSky.

Fomalhaut, bright and lonely

Fomalhaut, aka Alpha Piscis Austrinus, carries the nickname the Loneliest Star. It’s because Fomalhaut is the only bright star in a wide stretch of sky. From the Northern Hemisphere, in most years, Fomalhaut arcs in solitary splendor across the southern sky in autumn. Some also call it the Autumn Star. But in 2024, Fomalhaut isn’t so lonely. The bright planet Saturn is near it in the sky, so that – when you look southward on Northern Hemisphere autumn evenings – you see two bright objects. Fomalhaut will be the one that’s twinkling. Saturn will shine with a steady light.

From the Southern Hemisphere, you’ll look higher up to see Fomalhaut and Saturn in your season of spring.

Keep reading to learn more about Fomalhaut. It’s of special interest to astronomers because it has a debris ring around it. Astronomers think new worlds might be forming in Fomalhaut’s ring, as an early stage in the planet-forming process.

The star Fomalhaut as seen by an Earth-based telescope on November 13, 2008. Image via NASA/ ESA/ Digitized Sky Survey 2/ Davide De Martin (ESA/Hubble)/ ESA.

How to see it

Fomalhaut is the 18th brightest star in the night sky. It’s part of the faint constellation Piscis Austrinus the Southern Fish. In a dark sky, you’ll see a half-circle of faint stars of which bright Fomalhaut is a part. This star pattern marks the open mouth of the Southern Fish.

In early September, Fomalhaut is opposite the sun. So, it shines in the sky all night. It reaches its culmination – its highest point in the sky – around local midnight in mid-September.

Fomalhaut culminates at different times on different dates. Here are just a few approximate times and dates of culmination:

July 15: 4:30 a.m. daylight saving time (DST)
August 15: 2:30 a.m. DST
September 15: 12:30 a.m. DST
October 15: 10:30 p.m. DST
November 15: 8:30 p.m. DST
December 15: 5:30 p.m. standard time

The view from different hemispheres

From the Northern Hemisphere, you can see Fomalhaut from as far north as 60 degrees latitude (southern Alaska, central Canada, northern Europe), where it just skims the southern horizon. From the Southern Hemisphere, Fomalhaut appears much higher in the sky. You can use one of several stargazing smartphone apps, some that are free, to help you find it. Or visit Stellarium-Web.org, the free online planetarium, and enter your location and time.

Rings of dust and gas

Fomalhaut is a hot white star about 25 light-years away. It’s almost twice the mass and size of our sun but radiates over 16 times the sun’s energy. Fomalhaut has a companion star less than a light-year away from it. The companion is an orange dwarf star, about 70% the mass of our sun. A third member of the Fomalhaut star system was announced in 2013, a small reddish star about 2.5 light-years from Fomalhaut. From Earth, we see the third star located in the constellation Aquarius instead of Piscis Austrinus.

Fomalhaut itself is a young star, just 440 million years old. That’s in contrast to 4 1/2 billion years for our sun. Fomalhaut is of special interest to astronomers because it has several rings of dust and gas around it, early indications of planets in the process of formation around this star. Astronomers have detected inner debris disks close to the star, within a few astronomical units (AU) from the star.

There’s a much larger, thicker debris ring about 133 AU from the star. A study published in 2008 generated a lot of excitement when Hubble Space Telescope images, taken in 2004, 2006 and 2008 showed an apparent planet very close to this debris ring. Astronomers first thought it was the first directly imaged exoplanet. But data from other telescopes brought that conclusion under scrutiny. And, by 2014, this object was no longer visible to Hubble.

A possible explanation

So what happened? Astronomers think that the “planet” was actually a large dust cloud generated by the collision of two large bodies near the ring. And over time, that dust cloud may have dissipated. And even though it turned out not to be a planet, astronomers were pleased. Catching the aftermath of a collision in a planet-forming disk was good, too! The event provided clues to a deeper understanding about how planets form.

On the left, a Hubble Space Telescope image showing Fomalhaut’s debris disk. The star itself has been blocked so its brightness doesn’t drown out the view of the faint ring. The small box shows the object once thought to be a planet (but no more). On the right is a simulation, based on observations, of how the object appeared from 2004 to 2014. The object is now thought to be the result of a collision in the disk. Image via NASA.

Fomalhaut in history and mythology

The name Fomalhaut derives from the Arabic Fum al Hut, meaning Mouth of the Fish.

In the sky visible from the Northern Hemisphere, the constellation Aquarius the Water Bearer resides above Fomalhaut’s constellation Piscis Austrinus. You can see a zigzag line of stars from Aquarius to Piscis Austrinus. In sky lore, this line of stars represents water from the Jar of the Water Bearer, trickling into the open Mouth of the Fish.

According to Richard Hinckley Allen, Fomalhaut was one of the four guardians of the heavens to the ancient Persians, in 3,000 BCE, called by them Hastorang. (The other guardians were Aldebaran in Taurus, Antares in Scorpius, and Regulus in Leo.) Around 2,500 BCE, Fomalhaut helped mark the location of the winter solstice, meaning that it helped to define the location in the sky where the sun crossed the meridian at noon on the first day of winter. Also Allen also says that in 500 BCE, people worshipped Fomalhaut at the temple of Demeter in Eleusis, in ancient Greece.

View larger. | Aquarius the Water Carrier appears above Piscis Austrinus the Southern Fish, in the Celestial Atlas by Alexander Jamieson, published in 1822. In the illustration, water from the Water Jar of Aquarius is going into the Mouth of the Southern Fish. if it’s dark where you are, you can easily see a zigzag line of stars representing this flow of water. Image via Wikimedia (public domain).

Bottom line: Fomalhaut is known as the “lonely one” or “solitary one” because it shines brightly in an otherwise dim patch of sky. But in 2024, Saturn is nearby. Fomalhaut is of special interest to astronomers because of debris rings around it that are possibly the beginnings of a planetary system.

Read more: Fomalhaut has 3 nested belts around the star

The post Fomalhaut is the Loneliest Star … but not in 2024 first appeared on EarthSky.

from EarthSky https://ift.tt/se3d7TU

On October evenings in 2024, from the Northern Hemisphere, 2 objects can be seen sweeping across your southern sky. They are the Loneliest Star, Fomalhaut … not so lonely in 2024 because the golden planet Saturn is nearby. Fomalhaut and Saturn will be the brightest lights in that area of the sky. Watch for them! Chart via EarthSky.

Fomalhaut, bright and lonely

Fomalhaut, aka Alpha Piscis Austrinus, carries the nickname the Loneliest Star. It’s because Fomalhaut is the only bright star in a wide stretch of sky. From the Northern Hemisphere, in most years, Fomalhaut arcs in solitary splendor across the southern sky in autumn. Some also call it the Autumn Star. But in 2024, Fomalhaut isn’t so lonely. The bright planet Saturn is near it in the sky, so that – when you look southward on Northern Hemisphere autumn evenings – you see two bright objects. Fomalhaut will be the one that’s twinkling. Saturn will shine with a steady light.

From the Southern Hemisphere, you’ll look higher up to see Fomalhaut and Saturn in your season of spring.

Keep reading to learn more about Fomalhaut. It’s of special interest to astronomers because it has a debris ring around it. Astronomers think new worlds might be forming in Fomalhaut’s ring, as an early stage in the planet-forming process.

The star Fomalhaut as seen by an Earth-based telescope on November 13, 2008. Image via NASA/ ESA/ Digitized Sky Survey 2/ Davide De Martin (ESA/Hubble)/ ESA.

How to see it

Fomalhaut is the 18th brightest star in the night sky. It’s part of the faint constellation Piscis Austrinus the Southern Fish. In a dark sky, you’ll see a half-circle of faint stars of which bright Fomalhaut is a part. This star pattern marks the open mouth of the Southern Fish.

In early September, Fomalhaut is opposite the sun. So, it shines in the sky all night. It reaches its culmination – its highest point in the sky – around local midnight in mid-September.

Fomalhaut culminates at different times on different dates. Here are just a few approximate times and dates of culmination:

July 15: 4:30 a.m. daylight saving time (DST)
August 15: 2:30 a.m. DST
September 15: 12:30 a.m. DST
October 15: 10:30 p.m. DST
November 15: 8:30 p.m. DST
December 15: 5:30 p.m. standard time

The view from different hemispheres

From the Northern Hemisphere, you can see Fomalhaut from as far north as 60 degrees latitude (southern Alaska, central Canada, northern Europe), where it just skims the southern horizon. From the Southern Hemisphere, Fomalhaut appears much higher in the sky. You can use one of several stargazing smartphone apps, some that are free, to help you find it. Or visit Stellarium-Web.org, the free online planetarium, and enter your location and time.

Rings of dust and gas

Fomalhaut is a hot white star about 25 light-years away. It’s almost twice the mass and size of our sun but radiates over 16 times the sun’s energy. Fomalhaut has a companion star less than a light-year away from it. The companion is an orange dwarf star, about 70% the mass of our sun. A third member of the Fomalhaut star system was announced in 2013, a small reddish star about 2.5 light-years from Fomalhaut. From Earth, we see the third star located in the constellation Aquarius instead of Piscis Austrinus.

Fomalhaut itself is a young star, just 440 million years old. That’s in contrast to 4 1/2 billion years for our sun. Fomalhaut is of special interest to astronomers because it has several rings of dust and gas around it, early indications of planets in the process of formation around this star. Astronomers have detected inner debris disks close to the star, within a few astronomical units (AU) from the star.

There’s a much larger, thicker debris ring about 133 AU from the star. A study published in 2008 generated a lot of excitement when Hubble Space Telescope images, taken in 2004, 2006 and 2008 showed an apparent planet very close to this debris ring. Astronomers first thought it was the first directly imaged exoplanet. But data from other telescopes brought that conclusion under scrutiny. And, by 2014, this object was no longer visible to Hubble.

A possible explanation

So what happened? Astronomers think that the “planet” was actually a large dust cloud generated by the collision of two large bodies near the ring. And over time, that dust cloud may have dissipated. And even though it turned out not to be a planet, astronomers were pleased. Catching the aftermath of a collision in a planet-forming disk was good, too! The event provided clues to a deeper understanding about how planets form.

On the left, a Hubble Space Telescope image showing Fomalhaut’s debris disk. The star itself has been blocked so its brightness doesn’t drown out the view of the faint ring. The small box shows the object once thought to be a planet (but no more). On the right is a simulation, based on observations, of how the object appeared from 2004 to 2014. The object is now thought to be the result of a collision in the disk. Image via NASA.

Fomalhaut in history and mythology

The name Fomalhaut derives from the Arabic Fum al Hut, meaning Mouth of the Fish.

In the sky visible from the Northern Hemisphere, the constellation Aquarius the Water Bearer resides above Fomalhaut’s constellation Piscis Austrinus. You can see a zigzag line of stars from Aquarius to Piscis Austrinus. In sky lore, this line of stars represents water from the Jar of the Water Bearer, trickling into the open Mouth of the Fish.

According to Richard Hinckley Allen, Fomalhaut was one of the four guardians of the heavens to the ancient Persians, in 3,000 BCE, called by them Hastorang. (The other guardians were Aldebaran in Taurus, Antares in Scorpius, and Regulus in Leo.) Around 2,500 BCE, Fomalhaut helped mark the location of the winter solstice, meaning that it helped to define the location in the sky where the sun crossed the meridian at noon on the first day of winter. Also Allen also says that in 500 BCE, people worshipped Fomalhaut at the temple of Demeter in Eleusis, in ancient Greece.

View larger. | Aquarius the Water Carrier appears above Piscis Austrinus the Southern Fish, in the Celestial Atlas by Alexander Jamieson, published in 1822. In the illustration, water from the Water Jar of Aquarius is going into the Mouth of the Southern Fish. if it’s dark where you are, you can easily see a zigzag line of stars representing this flow of water. Image via Wikimedia (public domain).

Bottom line: Fomalhaut is known as the “lonely one” or “solitary one” because it shines brightly in an otherwise dim patch of sky. But in 2024, Saturn is nearby. Fomalhaut is of special interest to astronomers because of debris rings around it that are possibly the beginnings of a planetary system.

Read more: Fomalhaut has 3 nested belts around the star

The post Fomalhaut is the Loneliest Star … but not in 2024 first appeared on EarthSky.

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60% chance for La Niña in late 2024. Mild or cold winter?

La Niña in late 2024? Spanish for “the girl,” La Niña is a periodic cooling of ocean surface temperatures in the central and east-central equatorial Pacific. Typically, La Niña events occur every 3 to 5 years, but they can also happen over successive years, affecting weather around the globe. Image via NOAA’s World Ocean Database.

Will we have La Niña in late 2024?

NOAA’s Climate Prediction Center has issued a La Niña Watch, meaning that conditions are favorable for La Niña in late 2024 or early 2025. La Niña occurs when cold water from the depths of the equatorial Pacific rises up to the ocean surface, causing a change in weather patterns around the world.

NOAA is predicting a 60% chance for a weak La Niña event, developing in the Northern Hemisphere autumn months. And, if it happens, the La Niña is expected to persist through January-March, 2025. This event could lead to a dry and mild winter in the U.S. South and parts of Mexico, and a colder winter in the U.S. Northeast. And the northern tier of the U.S. and southern Canada could be wetter than average.

La Niña and El Niño are phases within the El Niño-Southern Oscillation, a naturally occurring global climate pattern. This pattern involves changes in wind and ocean temperatures in the Pacific and can cause extreme weather across the planet. La Nina is the cool phase of the pattern. And El Niño is the warm phase, occurring along with a weakening of trade winds that typically blow across the Pacific toward Asia. These winds weaken, allowing warm ocean waters to pile up along the western edge of South America.

A recent triple-dip La Niña

AP reported:

These cold ocean temperatures and changes in the atmosphere affect the position of the jet stream — a narrow band of fast moving air flowing from west to east around the planet—by bumping it northward. The jet stream sits over the ocean and can tap into its moisture, influence the path storms take and boost precipitation.

Just recently Earth experienced a ‘triple-dip’ La Niña event from 2020 to 2023. ‘We had three back-to-back winters where we had La Niña conditions, which was unusual because the only other case of that happening was back in 1973 to 1976,’ said Michelle L’Heurex, a climate scientist at NOAA.

L’Heurex said that La Niña’s tend to last longer and be more recurrent than El Niño events.

La Niña in late 2024? Ocean surface waters have been cooler than usual in recent months. Image via NOAA.

Bottom line: The National Oceanic and Atmospheric Administration (NOAA) has issued a La Niña for the northern autumn of 2024. If it happens, conditions will likely persist to early 2025.

Via AP

The post 60% chance for La Niña in late 2024. Mild or cold winter? first appeared on EarthSky.

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La Niña in late 2024? Spanish for “the girl,” La Niña is a periodic cooling of ocean surface temperatures in the central and east-central equatorial Pacific. Typically, La Niña events occur every 3 to 5 years, but they can also happen over successive years, affecting weather around the globe. Image via NOAA’s World Ocean Database.

Will we have La Niña in late 2024?

NOAA’s Climate Prediction Center has issued a La Niña Watch, meaning that conditions are favorable for La Niña in late 2024 or early 2025. La Niña occurs when cold water from the depths of the equatorial Pacific rises up to the ocean surface, causing a change in weather patterns around the world.

NOAA is predicting a 60% chance for a weak La Niña event, developing in the Northern Hemisphere autumn months. And, if it happens, the La Niña is expected to persist through January-March, 2025. This event could lead to a dry and mild winter in the U.S. South and parts of Mexico, and a colder winter in the U.S. Northeast. And the northern tier of the U.S. and southern Canada could be wetter than average.

La Niña and El Niño are phases within the El Niño-Southern Oscillation, a naturally occurring global climate pattern. This pattern involves changes in wind and ocean temperatures in the Pacific and can cause extreme weather across the planet. La Nina is the cool phase of the pattern. And El Niño is the warm phase, occurring along with a weakening of trade winds that typically blow across the Pacific toward Asia. These winds weaken, allowing warm ocean waters to pile up along the western edge of South America.

A recent triple-dip La Niña

AP reported:

These cold ocean temperatures and changes in the atmosphere affect the position of the jet stream — a narrow band of fast moving air flowing from west to east around the planet—by bumping it northward. The jet stream sits over the ocean and can tap into its moisture, influence the path storms take and boost precipitation.

Just recently Earth experienced a ‘triple-dip’ La Niña event from 2020 to 2023. ‘We had three back-to-back winters where we had La Niña conditions, which was unusual because the only other case of that happening was back in 1973 to 1976,’ said Michelle L’Heurex, a climate scientist at NOAA.

L’Heurex said that La Niña’s tend to last longer and be more recurrent than El Niño events.

La Niña in late 2024? Ocean surface waters have been cooler than usual in recent months. Image via NOAA.

Bottom line: The National Oceanic and Atmospheric Administration (NOAA) has issued a La Niña for the northern autumn of 2024. If it happens, conditions will likely persist to early 2025.

Via AP

The post 60% chance for La Niña in late 2024. Mild or cold winter? first appeared on EarthSky.

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The moon illusion makes the moon look huge!

The moon illusion is a trick of the mind

We’ve all seen a full moon looming large shortly after it rises, when it’s still hugging the horizon. And it’s true that the moon is sometimes closer to Earth than at other times, making it minutely larger in our sky. Yet the difference is barely discernible. When the moon viewed near the horizon looks larger than usual, your brain is playing a trick on you. It’s called the moon illusion.

You can check it out this week. On October 17, the Super Hunter’s Moon will be the closest supermoon in 2024. But even a brighter than normal supermoon will not look noticeably larger.

It’s all an illusion

We still don’t know the precise cause of the moon illusion. But the video above, from AsapSCIENCE, offers some explanations.

A common theory is when the moon is near the horizon, you’re seeing it in the company of many familiar visual reference points: trees, buildings, mountains and so on. Your brain automatically compares the moon to these reference points. But when the moon is higher up, there’s nothing to compare it to. As AsapSCIENCE says:

The moon seems smaller against the vastness of the night sky.

The moon looks bigger on the horizon. There is an optical illusion which makes the moon appear to be larger the lower it is in the sky. pic.twitter.com/zMAiAJ58g7

— Space Explorer Mike (@MichaelGalanin) August 28, 2017

Prove it to yourself

Maybe you’d like to test this theory yourself. According to NASA, here are some ways to prove it to yourself:

Hold up your outstretched index finger next to the moon. You’ll find that your fingernail and the moon are about the same size. Or try looking at the moon through a paper tube, or bend over and look backward between your legs. When you view it like this, the moon will be nowhere near as big as it had seemed.

Or NASA suggests:

Another ironclad way to size-check the moon is to take a photo when it’s near the horizon, and another when it’s high in the sky. If you keep your camera zoom settings the same, you’ll find that the moon is the same width, side to side, in both photos.

What about a red or orange moon?

By the way, there’s a second phenomenon that the moon displays when we see it near the horizon. That is, a low moon often appears red or orange in color. That reddish color is not an illusion. It’s a true physical effect, caused by the fact that – when the moon is low in the sky – you’re seeing it through a greater thickness of Earth’s atmosphere than when it’s overhead. The atmosphere filters out the bluer wavelengths of moonlight (which is really reflected sunlight). Meanwhile, it allows the red component of moonlight to travel straight through to your eyes. So a low moon is likely to look red or orange to you.

So how do people get those photos of extra big moons seen near a horizon? Photographers use zoom lenses and have familiar objects in the foreground making the more distant moon look huge. So they’re the result of photographic tricks and techniques, which you can read about here or here.

Some photos from our EarthSky Community

View at EarthSky Community Photos. | A great example of the moon illusion from Stephanie Becker in Soda Springs, California. She captured this image of the July full supermoon on July 2, 2023. Thank you, Stephanie!

View at EarthSky Community Photos. | Cecille Kennedy in Depoe Bay, Oregon, captured this image on August 30, 2023. Cecille wrote: “The blue supermoon shines behind the clouds as it rises over the hills and the trees. A few minutes before the moon rose, the clouds were lavender rose pink. Then the lovely moon appeared.” Thank you, Cecille!

Bottom line: It’s the Super Hunter’s Moon this week. You might see an extra-large-looking moon low in the sky. It’s the moon illusion that makes the moon look so big.

Did you get a great photo of the Super Hunter’s Moon? Submit your photos here. We love to see them!

The post The moon illusion makes the moon look huge! first appeared on EarthSky.

from EarthSky https://ift.tt/6ZpywJr

The moon illusion is a trick of the mind

We’ve all seen a full moon looming large shortly after it rises, when it’s still hugging the horizon. And it’s true that the moon is sometimes closer to Earth than at other times, making it minutely larger in our sky. Yet the difference is barely discernible. When the moon viewed near the horizon looks larger than usual, your brain is playing a trick on you. It’s called the moon illusion.

You can check it out this week. On October 17, the Super Hunter’s Moon will be the closest supermoon in 2024. But even a brighter than normal supermoon will not look noticeably larger.

It’s all an illusion

We still don’t know the precise cause of the moon illusion. But the video above, from AsapSCIENCE, offers some explanations.

A common theory is when the moon is near the horizon, you’re seeing it in the company of many familiar visual reference points: trees, buildings, mountains and so on. Your brain automatically compares the moon to these reference points. But when the moon is higher up, there’s nothing to compare it to. As AsapSCIENCE says:

The moon seems smaller against the vastness of the night sky.

The moon looks bigger on the horizon. There is an optical illusion which makes the moon appear to be larger the lower it is in the sky. pic.twitter.com/zMAiAJ58g7

— Space Explorer Mike (@MichaelGalanin) August 28, 2017

Prove it to yourself

Maybe you’d like to test this theory yourself. According to NASA, here are some ways to prove it to yourself:

Hold up your outstretched index finger next to the moon. You’ll find that your fingernail and the moon are about the same size. Or try looking at the moon through a paper tube, or bend over and look backward between your legs. When you view it like this, the moon will be nowhere near as big as it had seemed.

Or NASA suggests:

Another ironclad way to size-check the moon is to take a photo when it’s near the horizon, and another when it’s high in the sky. If you keep your camera zoom settings the same, you’ll find that the moon is the same width, side to side, in both photos.

What about a red or orange moon?

By the way, there’s a second phenomenon that the moon displays when we see it near the horizon. That is, a low moon often appears red or orange in color. That reddish color is not an illusion. It’s a true physical effect, caused by the fact that – when the moon is low in the sky – you’re seeing it through a greater thickness of Earth’s atmosphere than when it’s overhead. The atmosphere filters out the bluer wavelengths of moonlight (which is really reflected sunlight). Meanwhile, it allows the red component of moonlight to travel straight through to your eyes. So a low moon is likely to look red or orange to you.

So how do people get those photos of extra big moons seen near a horizon? Photographers use zoom lenses and have familiar objects in the foreground making the more distant moon look huge. So they’re the result of photographic tricks and techniques, which you can read about here or here.

Some photos from our EarthSky Community

View at EarthSky Community Photos. | A great example of the moon illusion from Stephanie Becker in Soda Springs, California. She captured this image of the July full supermoon on July 2, 2023. Thank you, Stephanie!

View at EarthSky Community Photos. | Cecille Kennedy in Depoe Bay, Oregon, captured this image on August 30, 2023. Cecille wrote: “The blue supermoon shines behind the clouds as it rises over the hills and the trees. A few minutes before the moon rose, the clouds were lavender rose pink. Then the lovely moon appeared.” Thank you, Cecille!

Bottom line: It’s the Super Hunter’s Moon this week. You might see an extra-large-looking moon low in the sky. It’s the moon illusion that makes the moon look so big.

Did you get a great photo of the Super Hunter’s Moon? Submit your photos here. We love to see them!

The post The moon illusion makes the moon look huge! first appeared on EarthSky.

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Sun officially reaches solar maximum in its 11-year cycle

Here’s a comparison of the sun at solar minimum, from December 2019, and solar maximum, from May 2024. Image via NASA/ SDO.

• NOAA and NASA announced solar maximum has arrived. Solar maximum is the peak of activity in the sun’s 11-year solar cycle.
• Signs of the peak of the sun’s cycle include the magnetic poles flipping and a high number of sunspots on the sun’s surface.
• We can still expect to see more aurora in the months to come. Scientists won’t know the exact month of the peak and its length until they look back on the data.

NASA published this original story on October 15, 2024. Edits by EarthSky.

We’re at the peak of the 11-year solar cycle

In a teleconference with reporters on Tuesday, October 15, 2024, representatives from NASA, the National Oceanic and Atmospheric Administration (NOAA), and the international Solar Cycle Prediction Panel announced that the sun has reached its solar maximum period, which could continue for the next year.

The solar cycle is a natural cycle the sun goes through as it transitions between low and high magnetic activity. Roughly every 11 years, at the height of the solar cycle, the sun’s magnetic poles flip — on Earth, that’d be like the North and South poles swapping places every decade — and the sun transitions from being calm to an active and stormy state.

NASA and NOAA track sunspots to determine and predict the progress of the solar cycle … and ultimately, solar activity. Sunspots are cooler regions on the sun caused by a concentration of magnetic field lines. Sunspots are the visible component of active regions, areas of intense and complex magnetic fields on the sun that are the source of solar eruptions.

Jamie Favors, director of the Space Weather Program at NASA Headquarters in Washington, said:

During solar maximum, the number of sunspots, and therefore, the amount of solar activity, increases. This increase in activity provides an exciting opportunity to learn about our closest star. But it also causes real effects at Earth and throughout our solar system.

Solar activity leads to space weather

Solar activity strongly influences conditions in space known as space weather. This can affect satellites and astronauts in space, as well as communications and navigation systems — such as radio and GPS — and power grids on Earth. When the sun is most active, space weather events become more frequent. Solar activity has led to increased aurora visibility and impacts on satellites and infrastructure in recent months.

During May 2024, a barrage of large solar flares and coronal mass ejections (CMEs) launched clouds of charged particles and magnetic fields toward Earth, creating the strongest geomagnetic storm at Earth in two decades. And it was possibly among the strongest displays of auroras on record in the past 500 years.

Elsayed Talaat, director of space weather operations at NOAA, said:

This announcement doesn’t mean that this is the peak of solar activity we’ll see this solar cycle. While the sun has reached the solar maximum period, the month that solar activity peaks on the sun will not be identified for months or years.

When is the exact peak of solar maximum?

Scientists will not be able to determine the exact peak of this solar maximum period for many months because it’s only identifiable after they’ve tracked a consistent decline in solar activity after that peak.

However, scientists have identified that the last two years on the sun have been part of this active phase of the solar cycle. That’s due to the consistently high number of sunspots during this period. Scientists anticipate the maximum phase will last another year or so before the sun enters the declining phase. And that leads back to solar minimum. Since 1989, the Solar Cycle Prediction Panel — an international panel of experts sponsored by NASA and NOAA — has worked together to make their prediction for the next solar cycle.

Solar cycles have been tracked by astronomers since Galileo first observed sunspots in the 1600s. Each solar cycle is different. Some cycles peak for larger and shorter amounts of time, and others have smaller peaks that last longer.

This is the sunspot number over the previous 24 solar cycles. Scientists use sunspots to track solar cycle progress. The dark spots are associated with solar activity, often as the origins for giant explosions. For example, solar flares or coronal mass ejections are giant explosions that can spew light, energy and solar material out into space. Image via NOAA’s Space Weather Prediction Center.

Solar maximum is slightly exceeding expectations

Lisa Upton, co-chair of the Solar Cycle Prediction Panel and lead scientist at Southwest Research Institute in San Antonio, Texas, said:

Solar Cycle 25 sunspot activity has slightly exceeded expectations. However, despite seeing a few large storms, they aren’t larger than what we might expect during the maximum phase of the cycle.

The most powerful flare of the solar cycle so far was an X9.0 on October 3. (X-class denotes the most intense flares, while the number provides more information about its strength.)

NOAA anticipates additional solar and geomagnetic storms during the current solar maximum period. This will lead to opportunities to spot auroras over the next several months, as well as potential technology impacts. Additionally, though less frequent, scientists often see fairly significant storms during the declining phase of the solar cycle.

The Solar Cycle 25 forecast, produced by the Solar Cycle 25 Prediction Panel, which is co-chaired by NASA and NOAA. Sunspot number is an indicator of solar cycle strength. The higher the sunspot number, the stronger the cycle. Image via NOAA’s Space Weather Prediction Center.

Future of space weather prediction

NASA and NOAA are preparing for the future of space weather research and prediction. In December 2024, NASA’s Parker Solar Probe mission will make its closest-ever approach to the sun, beating its own record of closest human-made object to the sun. This will be the first of three planned approaches for Parker at this distance, helping researchers to understand space weather right at the source.

NASA is launching several missions over the next year that will help us better understand space weather and its impacts across the solar system.

Space weather predictions are critical for supporting the spacecraft and astronauts of NASA’s Artemis campaign. Surveying this space environment is a vital part of understanding and mitigating astronaut exposure to space radiation.

NASA works as a research arm of the nation’s space weather effort. To see how space weather can affect Earth, please visit NOAA’s Space Weather Prediction Center, the U.S. government’s official source for space weather forecasts, watches, warnings, and alerts.

Bottom line: NASA and NOAA announced on October 15, 2024, that the sun has reached the peak of its 11-year solar cycle, or what is known as solar maximum.

Via NASA

Keep up-to-date with solar activity via our daily sun post!

The post Sun officially reaches solar maximum in its 11-year cycle first appeared on EarthSky.

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Here’s a comparison of the sun at solar minimum, from December 2019, and solar maximum, from May 2024. Image via NASA/ SDO.

• NOAA and NASA announced solar maximum has arrived. Solar maximum is the peak of activity in the sun’s 11-year solar cycle.
• Signs of the peak of the sun’s cycle include the magnetic poles flipping and a high number of sunspots on the sun’s surface.
• We can still expect to see more aurora in the months to come. Scientists won’t know the exact month of the peak and its length until they look back on the data.

NASA published this original story on October 15, 2024. Edits by EarthSky.

We’re at the peak of the 11-year solar cycle

In a teleconference with reporters on Tuesday, October 15, 2024, representatives from NASA, the National Oceanic and Atmospheric Administration (NOAA), and the international Solar Cycle Prediction Panel announced that the sun has reached its solar maximum period, which could continue for the next year.

The solar cycle is a natural cycle the sun goes through as it transitions between low and high magnetic activity. Roughly every 11 years, at the height of the solar cycle, the sun’s magnetic poles flip — on Earth, that’d be like the North and South poles swapping places every decade — and the sun transitions from being calm to an active and stormy state.

NASA and NOAA track sunspots to determine and predict the progress of the solar cycle … and ultimately, solar activity. Sunspots are cooler regions on the sun caused by a concentration of magnetic field lines. Sunspots are the visible component of active regions, areas of intense and complex magnetic fields on the sun that are the source of solar eruptions.

Jamie Favors, director of the Space Weather Program at NASA Headquarters in Washington, said:

During solar maximum, the number of sunspots, and therefore, the amount of solar activity, increases. This increase in activity provides an exciting opportunity to learn about our closest star. But it also causes real effects at Earth and throughout our solar system.

Solar activity leads to space weather

Solar activity strongly influences conditions in space known as space weather. This can affect satellites and astronauts in space, as well as communications and navigation systems — such as radio and GPS — and power grids on Earth. When the sun is most active, space weather events become more frequent. Solar activity has led to increased aurora visibility and impacts on satellites and infrastructure in recent months.

During May 2024, a barrage of large solar flares and coronal mass ejections (CMEs) launched clouds of charged particles and magnetic fields toward Earth, creating the strongest geomagnetic storm at Earth in two decades. And it was possibly among the strongest displays of auroras on record in the past 500 years.

Elsayed Talaat, director of space weather operations at NOAA, said:

This announcement doesn’t mean that this is the peak of solar activity we’ll see this solar cycle. While the sun has reached the solar maximum period, the month that solar activity peaks on the sun will not be identified for months or years.

When is the exact peak of solar maximum?

Scientists will not be able to determine the exact peak of this solar maximum period for many months because it’s only identifiable after they’ve tracked a consistent decline in solar activity after that peak.

However, scientists have identified that the last two years on the sun have been part of this active phase of the solar cycle. That’s due to the consistently high number of sunspots during this period. Scientists anticipate the maximum phase will last another year or so before the sun enters the declining phase. And that leads back to solar minimum. Since 1989, the Solar Cycle Prediction Panel — an international panel of experts sponsored by NASA and NOAA — has worked together to make their prediction for the next solar cycle.

Solar cycles have been tracked by astronomers since Galileo first observed sunspots in the 1600s. Each solar cycle is different. Some cycles peak for larger and shorter amounts of time, and others have smaller peaks that last longer.

This is the sunspot number over the previous 24 solar cycles. Scientists use sunspots to track solar cycle progress. The dark spots are associated with solar activity, often as the origins for giant explosions. For example, solar flares or coronal mass ejections are giant explosions that can spew light, energy and solar material out into space. Image via NOAA’s Space Weather Prediction Center.

Solar maximum is slightly exceeding expectations

Lisa Upton, co-chair of the Solar Cycle Prediction Panel and lead scientist at Southwest Research Institute in San Antonio, Texas, said:

Solar Cycle 25 sunspot activity has slightly exceeded expectations. However, despite seeing a few large storms, they aren’t larger than what we might expect during the maximum phase of the cycle.

The most powerful flare of the solar cycle so far was an X9.0 on October 3. (X-class denotes the most intense flares, while the number provides more information about its strength.)

NOAA anticipates additional solar and geomagnetic storms during the current solar maximum period. This will lead to opportunities to spot auroras over the next several months, as well as potential technology impacts. Additionally, though less frequent, scientists often see fairly significant storms during the declining phase of the solar cycle.

The Solar Cycle 25 forecast, produced by the Solar Cycle 25 Prediction Panel, which is co-chaired by NASA and NOAA. Sunspot number is an indicator of solar cycle strength. The higher the sunspot number, the stronger the cycle. Image via NOAA’s Space Weather Prediction Center.

Future of space weather prediction

NASA and NOAA are preparing for the future of space weather research and prediction. In December 2024, NASA’s Parker Solar Probe mission will make its closest-ever approach to the sun, beating its own record of closest human-made object to the sun. This will be the first of three planned approaches for Parker at this distance, helping researchers to understand space weather right at the source.

NASA is launching several missions over the next year that will help us better understand space weather and its impacts across the solar system.

Space weather predictions are critical for supporting the spacecraft and astronauts of NASA’s Artemis campaign. Surveying this space environment is a vital part of understanding and mitigating astronaut exposure to space radiation.

NASA works as a research arm of the nation’s space weather effort. To see how space weather can affect Earth, please visit NOAA’s Space Weather Prediction Center, the U.S. government’s official source for space weather forecasts, watches, warnings, and alerts.

Bottom line: NASA and NOAA announced on October 15, 2024, that the sun has reached the peak of its 11-year solar cycle, or what is known as solar maximum.

Via NASA

Keep up-to-date with solar activity via our daily sun post!

The post Sun officially reaches solar maximum in its 11-year cycle first appeared on EarthSky.

from EarthSky https://ift.tt/1gTcnPS