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Space is getting crowded. Here’s the latest satellite report

Earth orbit is getting more crowded, and the consequences could be serious. The European Space Agency’s 2026 Space Environment Report warns that debris collisions could trigger a runaway chain reaction, making some orbital regions unsafe or unusable. Space hazards expert Jonathan McDowell joins EarthSky to explain what the report reveals, how dangerous conditions in space have become, and what we can do about it. Watch in the player above.

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

Space is getting crowded. Let’s look at the numbers

In September 2026, ESA’s Space Debris Office published its annual Space Environment Report. And, as you might suspect, the news is that space — in particular low Earth orbit — is getting more crowded. Here’s a look at the basic numbers as of October 2026 from OrbitalRadar.com:

  • 31,000+ total tracked objects in low Earth orbit
  • 18,600+ payloads in orbit, working and nonworking
  • 15,800+ of those are working satellites
  • 10,000+ of the working satellites are Starlink

And, according to ESA, the only place those numbers are going to go is up. ESA, which based its report on data through 2025, outlined some of the biggest concerns:

  • The number and scale of commercial satellite constellations continue to increase each year.  
  • Not enough satellites leave heavily congested orbits at the end of their lives, creating a growing collision risk. The expected number of objects and collisions in low-Earth orbit are skyrocketing in a runaway effect. (Read more: The Kessler syndrome) 
  • More than three intact satellites or rocket bodies are reentering every day. Plus, 10 new payloads are launched daily. (Read more: 1 to 2 Starlink satellites are falling back to Earth each day)
  • In 2026, ESA added an on-ground casualty risk of reentries. While the risk is still very low, the chance is still increasing every year due to increased traffic.  

Let’s visualize the numbers

Here are some graphics from ESA to help us visualize the numbers of satellites in orbit and being added to orbit.

Graph with small vertical bars at left until the last 1/7 of the graph the bars get tall with different colors.
This graph from ESA shows how in the last 5 years the number of satellites launched into low Earth orbit has skyrocketed. Image via ESA.
Graph with a slowly rising curve until the end when it starts to jut up sharply.
According to ESA, the overall number of objects in low Earth orbit is rapidly increasing. That includes working payloads along with nonworking satellites and debris from collisions. Image via ESA.

The pluses and minuses of reentry

Because there are now so many satellites in low Earth orbit, it’s important that they get removed from orbit when they’ve reached the end of their lives. And one of the positive findings of ESA’s 2026 report was that there are more controlled reentries now. That means companies and governments are conducting planned end-of-life disposal of their satellites.

But reentries have drawbacks. As they burn up in our atmosphere, they deposit heavy metals. There are many issues this deposit could lead to, include damaging the ozone layer, affecting the climate and altering the atmosphere’s natural chemistry.

And then, of course, there’s the new metric ESA introduced this year: the risk of casualties on the ground. While you are still much more likely to be injured or killed in a car or on a staircase, the risk of harm from satellite reentry has naturally gone up as the number of reentering satellites goes up. More controlled reentries would help to mitigate this risk.

Graph showing undulating vertical bars growing steadily taller at the very right side.
What goes up must come down … eventually. This ESA graph shows how the number of reentering satellites has sharply increased in the last few years. Image via ESA.
Graph with a red line slowly increasing and the yellow line following a similar route, with broken yellow line lower.
While the risk of death or injury from a reentering satellite or rocket body that lifted the satellite into orbit is still extremely low, the numbers are rising nonetheless. Image via ESA.

Space is getting crowded: What are the real risks?

The biggest immediate concern, as we send more and more satellites into low Earth orbit, is that the rising population seems unstoppable. That is, until collisions cascade into more collisions and make the environment unusable.

This idea that satellites will collide and create debris that produces more collisions until we have a runaway cascading effect is called the Kessler syndrome.

As recently as October 5, 2026, LeoLabs detected a satellite breakup in a crowded low-Earth environment. LeoLabs spotted multiple objects near the inactive Meteor 2-7 satellite after it passed over a radar station in Western Australia. Followup observations from other radars confirmed that a debris-generating event occurred. The company called it a:

… worrying trend for space safety and security.

But ESA — along with other space organizations — is working on ways to reduce the risk. This will involve cleaning up orbits and working toward a zero debris solution.

Bottom line: ESA has put out an annual report documenting the state of low Earth orbit. The number of satellites in orbit is skyrocketing, along with the chance for collisions and on-ground casualties.

Via ESA

The post Space is getting crowded. Here’s the latest satellite report first appeared on EarthSky.



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Earth orbit is getting more crowded, and the consequences could be serious. The European Space Agency’s 2026 Space Environment Report warns that debris collisions could trigger a runaway chain reaction, making some orbital regions unsafe or unusable. Space hazards expert Jonathan McDowell joins EarthSky to explain what the report reveals, how dangerous conditions in space have become, and what we can do about it. Watch in the player above.

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

Space is getting crowded. Let’s look at the numbers

In September 2026, ESA’s Space Debris Office published its annual Space Environment Report. And, as you might suspect, the news is that space — in particular low Earth orbit — is getting more crowded. Here’s a look at the basic numbers as of October 2026 from OrbitalRadar.com:

  • 31,000+ total tracked objects in low Earth orbit
  • 18,600+ payloads in orbit, working and nonworking
  • 15,800+ of those are working satellites
  • 10,000+ of the working satellites are Starlink

And, according to ESA, the only place those numbers are going to go is up. ESA, which based its report on data through 2025, outlined some of the biggest concerns:

  • The number and scale of commercial satellite constellations continue to increase each year.  
  • Not enough satellites leave heavily congested orbits at the end of their lives, creating a growing collision risk. The expected number of objects and collisions in low-Earth orbit are skyrocketing in a runaway effect. (Read more: The Kessler syndrome) 
  • More than three intact satellites or rocket bodies are reentering every day. Plus, 10 new payloads are launched daily. (Read more: 1 to 2 Starlink satellites are falling back to Earth each day)
  • In 2026, ESA added an on-ground casualty risk of reentries. While the risk is still very low, the chance is still increasing every year due to increased traffic.  

Let’s visualize the numbers

Here are some graphics from ESA to help us visualize the numbers of satellites in orbit and being added to orbit.

Graph with small vertical bars at left until the last 1/7 of the graph the bars get tall with different colors.
This graph from ESA shows how in the last 5 years the number of satellites launched into low Earth orbit has skyrocketed. Image via ESA.
Graph with a slowly rising curve until the end when it starts to jut up sharply.
According to ESA, the overall number of objects in low Earth orbit is rapidly increasing. That includes working payloads along with nonworking satellites and debris from collisions. Image via ESA.

The pluses and minuses of reentry

Because there are now so many satellites in low Earth orbit, it’s important that they get removed from orbit when they’ve reached the end of their lives. And one of the positive findings of ESA’s 2026 report was that there are more controlled reentries now. That means companies and governments are conducting planned end-of-life disposal of their satellites.

But reentries have drawbacks. As they burn up in our atmosphere, they deposit heavy metals. There are many issues this deposit could lead to, include damaging the ozone layer, affecting the climate and altering the atmosphere’s natural chemistry.

And then, of course, there’s the new metric ESA introduced this year: the risk of casualties on the ground. While you are still much more likely to be injured or killed in a car or on a staircase, the risk of harm from satellite reentry has naturally gone up as the number of reentering satellites goes up. More controlled reentries would help to mitigate this risk.

Graph showing undulating vertical bars growing steadily taller at the very right side.
What goes up must come down … eventually. This ESA graph shows how the number of reentering satellites has sharply increased in the last few years. Image via ESA.
Graph with a red line slowly increasing and the yellow line following a similar route, with broken yellow line lower.
While the risk of death or injury from a reentering satellite or rocket body that lifted the satellite into orbit is still extremely low, the numbers are rising nonetheless. Image via ESA.

Space is getting crowded: What are the real risks?

The biggest immediate concern, as we send more and more satellites into low Earth orbit, is that the rising population seems unstoppable. That is, until collisions cascade into more collisions and make the environment unusable.

This idea that satellites will collide and create debris that produces more collisions until we have a runaway cascading effect is called the Kessler syndrome.

As recently as October 5, 2026, LeoLabs detected a satellite breakup in a crowded low-Earth environment. LeoLabs spotted multiple objects near the inactive Meteor 2-7 satellite after it passed over a radar station in Western Australia. Followup observations from other radars confirmed that a debris-generating event occurred. The company called it a:

… worrying trend for space safety and security.

But ESA — along with other space organizations — is working on ways to reduce the risk. This will involve cleaning up orbits and working toward a zero debris solution.

Bottom line: ESA has put out an annual report documenting the state of low Earth orbit. The number of satellites in orbit is skyrocketing, along with the chance for collisions and on-ground casualties.

Via ESA

The post Space is getting crowded. Here’s the latest satellite report first appeared on EarthSky.



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Cassiopeia the Queen is overhead on autumn evenings

Cassiopeia overhead on autumn evenings

The constellation Cassiopeia the Queen can be found high in the sky on October and November evenings, not far from Polaris, the North Star. And at any time of year, you can use the Big Dipper to find Cassiopeia. These two star formations are like riders on opposite sides of a Ferris wheel. In fact, they’re part of a great spinning wheel of stars seen moving counterclockwise around Polaris, the North Star, once each day. Whenever Cassiopeia rises upward, the Big Dipper plunges downward, and vice versa.

Some of you know how to star-hop to Polaris, the North Star, by using the Big Dipper’s pointer stars, as displayed on the sky chart below. That’s because the Big Dipper’s handle and Cassiopeia shine on opposite sides of Polaris, an imaginary line from any star on the Big Dipper handle through Polaris reliably points to Cassiopeia.

Star chart with constellations and animation of arrows pointing from the Big Dipper to Polaris to Cassiopeia.
You can find Cassiopeia somewhere in the north for much of the year, and much of the night. And here it is on autumn evenings relative to Polaris, the North Star. But no matter the time of year, you can use the Big Dipper and Polaris to find Cassiopeia. Chart via Stellarium.org. Used with permission.

Cassiopeia is bright and easy to pick out in the sky

However, you won’t need the Big Dipper and Polaris to find Cassiopeia. That’s because Cassiopeia is very easy to pick out. Even thought it’s small and compact, it has a distinctive pattern. As you can see, it looks like the letter M or W, depending on the time of night and time of year.

Like the Big Dipper, Cassiopeia is visible even on moonlit nights.

Plus, there’s a bonus for you if you live north of about 40 degrees north latitude, about the latitude of New York City! From that latitude and farther north, the Big Dipper and Cassiopeia are both circumpolar. So that means they’re always above the horizon at any time of night, all year round.

Sky chart of constellation Cassiopeia with stars in black on white and other objects as small colored symbols.
Chart of the constellation Cassiopeia the Queen. Obviously spotting a pattern of stars shaped as a M or W makes Cassiopeia an easy constellation to find. Chart via IAU. Used with permission.

Star lore of Cassiopeia

Cassiopeia used to be known among astronomers and skywatchers alike as Cassiopeia’s Chair. In the 1930s, the International Astronomical Union gave this constellation the official name of Cassiopeia the Queen.

Cassiopeia was a queen in ancient Greek mythology. According to legend, she boasted she was more beautiful than the sea nymphs called the Nereids. Her boast angered Poseidon, god of the sea, who sent a sea monster, Cetus, to ravage the kingdom. To pacify the monster, Cassiopeia’s daughter, Princess Andromeda, was left tied to a rock by the sea. Cetus was about to devour her when Perseus the Hero looked down upon her from Pegasus, the Flying Horse. Perseus rescued the Princess, and all lived happily.

The gods were so pleased, they elevated all these characters to the heavens as stars. However, Cassiopeia suffered an indignity; her vanity caused her to be bound to a chair and placed in the heavens so that, as she revolves around the north celestial pole, she is sometimes in an upside-down position.

Old-fashioned drawing of Queen Cassiopeia in Greek garb on her throne, with scattered stars.
Cassiopeia as depicted by Johannes Hevelius in the 1600s. Image via Wikimedia Commons (public domain).

Bottom line: Spot the constellation Cassiopeia the Queen somewhere in the northern sky during much of the year, and throughout much of the night. It’s high overhead now.

The post Cassiopeia the Queen is overhead on autumn evenings first appeared on EarthSky.



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Cassiopeia overhead on autumn evenings

The constellation Cassiopeia the Queen can be found high in the sky on October and November evenings, not far from Polaris, the North Star. And at any time of year, you can use the Big Dipper to find Cassiopeia. These two star formations are like riders on opposite sides of a Ferris wheel. In fact, they’re part of a great spinning wheel of stars seen moving counterclockwise around Polaris, the North Star, once each day. Whenever Cassiopeia rises upward, the Big Dipper plunges downward, and vice versa.

Some of you know how to star-hop to Polaris, the North Star, by using the Big Dipper’s pointer stars, as displayed on the sky chart below. That’s because the Big Dipper’s handle and Cassiopeia shine on opposite sides of Polaris, an imaginary line from any star on the Big Dipper handle through Polaris reliably points to Cassiopeia.

Star chart with constellations and animation of arrows pointing from the Big Dipper to Polaris to Cassiopeia.
You can find Cassiopeia somewhere in the north for much of the year, and much of the night. And here it is on autumn evenings relative to Polaris, the North Star. But no matter the time of year, you can use the Big Dipper and Polaris to find Cassiopeia. Chart via Stellarium.org. Used with permission.

Cassiopeia is bright and easy to pick out in the sky

However, you won’t need the Big Dipper and Polaris to find Cassiopeia. That’s because Cassiopeia is very easy to pick out. Even thought it’s small and compact, it has a distinctive pattern. As you can see, it looks like the letter M or W, depending on the time of night and time of year.

Like the Big Dipper, Cassiopeia is visible even on moonlit nights.

Plus, there’s a bonus for you if you live north of about 40 degrees north latitude, about the latitude of New York City! From that latitude and farther north, the Big Dipper and Cassiopeia are both circumpolar. So that means they’re always above the horizon at any time of night, all year round.

Sky chart of constellation Cassiopeia with stars in black on white and other objects as small colored symbols.
Chart of the constellation Cassiopeia the Queen. Obviously spotting a pattern of stars shaped as a M or W makes Cassiopeia an easy constellation to find. Chart via IAU. Used with permission.

Star lore of Cassiopeia

Cassiopeia used to be known among astronomers and skywatchers alike as Cassiopeia’s Chair. In the 1930s, the International Astronomical Union gave this constellation the official name of Cassiopeia the Queen.

Cassiopeia was a queen in ancient Greek mythology. According to legend, she boasted she was more beautiful than the sea nymphs called the Nereids. Her boast angered Poseidon, god of the sea, who sent a sea monster, Cetus, to ravage the kingdom. To pacify the monster, Cassiopeia’s daughter, Princess Andromeda, was left tied to a rock by the sea. Cetus was about to devour her when Perseus the Hero looked down upon her from Pegasus, the Flying Horse. Perseus rescued the Princess, and all lived happily.

The gods were so pleased, they elevated all these characters to the heavens as stars. However, Cassiopeia suffered an indignity; her vanity caused her to be bound to a chair and placed in the heavens so that, as she revolves around the north celestial pole, she is sometimes in an upside-down position.

Old-fashioned drawing of Queen Cassiopeia in Greek garb on her throne, with scattered stars.
Cassiopeia as depicted by Johannes Hevelius in the 1600s. Image via Wikimedia Commons (public domain).

Bottom line: Spot the constellation Cassiopeia the Queen somewhere in the northern sky during much of the year, and throughout much of the night. It’s high overhead now.

The post Cassiopeia the Queen is overhead on autumn evenings first appeared on EarthSky.



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What star in the northeast flashes colorfully? It’s Capella!

Star chart: Roundish constellation Auriga with stars and other objects labeled.
The bright star Capella in the constellation Auriga the Charioteer flashes red, green and blue in the northeast on northern autumn evenings. Around October in the Northern Hemisphere, many people look at this star and wonder if they’re seeing a UFO. To be sure you’ve found Capella, look for a little triangle of stars next to it. This little triangular asterism is called The Kids.

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Capella is the colorful, twinkling star in the northeast

This evening, check out one of the flashiest stars in the sky. It’s the brightest star in the northeast this month. It’s so bright that every year in northern autumn, we get questions from people in the Northern Hemisphere who see a star twinkling with colorful flashes. It lies low in the northeastern sky in early evening as seen from mid-northern locations. That star is Capella.

The reason it’s so flashy is because it’s a bright star shining near the horizon. That means its light is coming to us through our thick atmosphere. The wavering air makes its point of light jump around, split into colors and appear to flash.

If you could travel to it in space, you’d find that Capella is really two golden stars, both with roughly the same surface temperature as our local star, the sun … but both larger and brighter.

Capella is in the constellation Auriga the Charioteer. Since antiquity, Capella’s nickname has been the Goat Star. You might pick it out just by gazing northeastward from a Northern Hemisphere latitude during the evening hours in October. Capella climbs upward throughout the night, and this month soars high overhead in the wee hours before dawn.

Why stars twinkle or flash

So, Capella is a golden point of light that flashes red and green when it’s low in the sky. Why does it do that?

The reality is that every star in the sky undergoes the same process as Capella when it twinkles. That is, every star’s light must shine through Earth’s atmosphere before reaching our eyes. But not every star flashes as noticeably as Capella. The flashes happen because Capella is low in the sky in the evening at this time of the year. And, when you look at an object low in the sky, you’re looking through more atmosphere than when the same object is overhead.

The atmosphere splits or refracts the star’s light, just as a prism splits sunlight.

So that’s where Capella’s red and green flashes are coming from — not from the star itself, but from the refraction of its light by our atmosphere. When you see Capella higher in the sky, you’ll find that these glints of color will disappear.

By the way, why are these flashes of color so especially noticeable with Capella? The reason is simply that it’s a very bright star. It’s the sixth brightest star in Earth’s sky, not including our sun.

Here are 2 other flashing stars of autumn

If the flashy star you’re seeing doesn’t seem to be Capella (wrong time, wrong location), here are a couple of other options. Arcturus is in the northwest at this time of year. Follow the curving handle of the Big Dipper toward the horizon, and if it hits the star you’re wondering about, then you’re looking at Arcturus in Boötes.

Another option is Sirius. If you’re waking before dawn this time of the year, you’ll find Sirius toward the south. Check out the maps below to see which star is twinkling at you.

Chart of the Big Dipper with a line following the Dipper's handle to Arcturus.
Look northwest soon after sunset in October to find the star Arcturus in the constellation Boötes and the Big Dipper asterism. The curve in the Dipper’s handle always points to Arcturus, one of autumn’s 3 flashiest stars. Just be sure to look not long after nightfall. Unlike Capella, which ascends in the northeastern sky throughout the evening, Arcturus sets not long after sunset.
Star chart of Orion - that looks like an hourglass with arms - and arrow from Orion's Belt to Sirius.
Look southward before dawn to see the star Sirius in October. At this time of the year, we get many, many questions about a multicolored star twinkling in the southeastern to southern sky after midnight. This star typically turns out to be Sirius, which is in the constellation Canis Major the Greater Dog and is sometimes called the Dog Star. Notice that a line from Orion’s Belt points to Sirius.

Bottom line: If you’re in Earth’s Northern Hemisphere and see a bright star twinkling with red and green flashes low in the northeast on October evenings, it’s probably Capella.

The post What star in the northeast flashes colorfully? It’s Capella! first appeared on EarthSky.



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Star chart: Roundish constellation Auriga with stars and other objects labeled.
The bright star Capella in the constellation Auriga the Charioteer flashes red, green and blue in the northeast on northern autumn evenings. Around October in the Northern Hemisphere, many people look at this star and wonder if they’re seeing a UFO. To be sure you’ve found Capella, look for a little triangle of stars next to it. This little triangular asterism is called The Kids.

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

Capella is the colorful, twinkling star in the northeast

This evening, check out one of the flashiest stars in the sky. It’s the brightest star in the northeast this month. It’s so bright that every year in northern autumn, we get questions from people in the Northern Hemisphere who see a star twinkling with colorful flashes. It lies low in the northeastern sky in early evening as seen from mid-northern locations. That star is Capella.

The reason it’s so flashy is because it’s a bright star shining near the horizon. That means its light is coming to us through our thick atmosphere. The wavering air makes its point of light jump around, split into colors and appear to flash.

If you could travel to it in space, you’d find that Capella is really two golden stars, both with roughly the same surface temperature as our local star, the sun … but both larger and brighter.

Capella is in the constellation Auriga the Charioteer. Since antiquity, Capella’s nickname has been the Goat Star. You might pick it out just by gazing northeastward from a Northern Hemisphere latitude during the evening hours in October. Capella climbs upward throughout the night, and this month soars high overhead in the wee hours before dawn.

Why stars twinkle or flash

So, Capella is a golden point of light that flashes red and green when it’s low in the sky. Why does it do that?

The reality is that every star in the sky undergoes the same process as Capella when it twinkles. That is, every star’s light must shine through Earth’s atmosphere before reaching our eyes. But not every star flashes as noticeably as Capella. The flashes happen because Capella is low in the sky in the evening at this time of the year. And, when you look at an object low in the sky, you’re looking through more atmosphere than when the same object is overhead.

The atmosphere splits or refracts the star’s light, just as a prism splits sunlight.

So that’s where Capella’s red and green flashes are coming from — not from the star itself, but from the refraction of its light by our atmosphere. When you see Capella higher in the sky, you’ll find that these glints of color will disappear.

By the way, why are these flashes of color so especially noticeable with Capella? The reason is simply that it’s a very bright star. It’s the sixth brightest star in Earth’s sky, not including our sun.

Here are 2 other flashing stars of autumn

If the flashy star you’re seeing doesn’t seem to be Capella (wrong time, wrong location), here are a couple of other options. Arcturus is in the northwest at this time of year. Follow the curving handle of the Big Dipper toward the horizon, and if it hits the star you’re wondering about, then you’re looking at Arcturus in Boötes.

Another option is Sirius. If you’re waking before dawn this time of the year, you’ll find Sirius toward the south. Check out the maps below to see which star is twinkling at you.

Chart of the Big Dipper with a line following the Dipper's handle to Arcturus.
Look northwest soon after sunset in October to find the star Arcturus in the constellation Boötes and the Big Dipper asterism. The curve in the Dipper’s handle always points to Arcturus, one of autumn’s 3 flashiest stars. Just be sure to look not long after nightfall. Unlike Capella, which ascends in the northeastern sky throughout the evening, Arcturus sets not long after sunset.
Star chart of Orion - that looks like an hourglass with arms - and arrow from Orion's Belt to Sirius.
Look southward before dawn to see the star Sirius in October. At this time of the year, we get many, many questions about a multicolored star twinkling in the southeastern to southern sky after midnight. This star typically turns out to be Sirius, which is in the constellation Canis Major the Greater Dog and is sometimes called the Dog Star. Notice that a line from Orion’s Belt points to Sirius.

Bottom line: If you’re in Earth’s Northern Hemisphere and see a bright star twinkling with red and green flashes low in the northeast on October evenings, it’s probably Capella.

The post What star in the northeast flashes colorfully? It’s Capella! first appeared on EarthSky.



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Best deep-sky photos of September 2026 from EarthSky community

A large area of blue nebulosity with bright white stars immersed within.
View at EarthSky Community Photos. | Muhammad Alaa in Egypt used a smart telescope to capture this view of the Pleiades open cluster on September 15, 2026. Muhammad wrote: “One of the most beautiful open star clusters in the night sky, surrounded by stunning blue reflection nebulosity.” Thank you, Muhammad! See more deep-sky photos from September 2026 below.

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Thank you, EarthSky community

The EarthSky community has many talented astrophotographers who capture stunning images of the deep sky. We gathered some of our favorite deep-sky photos from September 2026 for you to enjoy. Do you have images of your own to share? You can submit them to EarthSky here. We’d love to see them and share them!

Deep-sky photos of diffuse nebulae

A huge, complex red nebula with small blue swirls and a background of thousands of faint stars.
View at EarthSky Community Photos. | Ernest Jacobs in Eden, New York, captured this telescopic view of nebulae surrounding the star WR134 on September 6, 2026. Ernest wrote: “WR 134 (also known as V1769 Cyg) is a Wolf-Rayet star—a massive, hot, and rapidly shedding stellar core in its final stages of life. It has a surface temperature of about 63,000 K and a luminosity roughly 400,000 times that of the sun. WR 134 is located in the constellation Cygnus about 6,000 light-years from Earth. This image was captured over 3 nights with my wide-field deep sky imaging rig from my backyard.” Thank you, Ernest!
A large, multicolor arc of nebulosity, with numerous stars immersed within and in the surroundings.
View at EarthSky Community Photos. | Cody Sandusky in Harrisburg, Illinois, used a smart telescope to capture a part of the Veil Nebula, in the constellation Cygnus, on September 15, 2026. Cody wrote: “NGC 6960, the Western Veil Nebula, captured over five nights (approximately 15 hours of integration time) from my back yard.” Thank you, Cody!
A large, complex, orange mass of gas with blue highlights, dark lanes and numerous foreground stars.
View at EarthSky Community Photos. | Andy Dungan near Cotopaxi, Colorado, captured this telescopic view of the Wizard Nebula, in the constellation Cepheus, on September 3, 2026. Andy wrote: “I remember taking a pic of the Wizard Nebula 2 years ago. It was basically a red blob. By using narrow-band filters I really get more information and can color it in more unique ways.” Thank you, Andy!
Two large, complex, yellowish mass of gas with blue highlights and numerous foreground stars.
View at EarthSky Community Photos. | Muhammad Alaa in Assiut, Egypt, used a smart telescope to capture this view of the Heart and Soul nebulae on September 24, 2025. Muhammad calls this image a labor of love, and wrote: “The Heart and Soul Nebulae (IC 1805 and IC 1848) are two spectacular emission nebulae located in the constellation Cassiopeia, filled with glowing hydrogen gas and intricate clouds of interstellar dust. I truly love this image. This one was a little challenging to process, especially bringing out the delicate hydrogen-alpha + oxygen III emissions while preserving the natural structure and fine details of the nebulae.” Thank you, Muhammad!

Deep-sky photos of distant galaxies

Whitish spiral galaxy seen head-on, with dark lanes and sparse foreground stars.
View at EarthSky Community Photos. | Catherine Hyde in Cambria, California, captured this telescopic view of galaxy Messier 74, in the constellation Pisces, on September 19, 2026. Catherine wrote: “This is the big, beautiful face-on spiral galaxy M74 in the constellation Pisces. This is 134 images, 300 seconds each, stacked, for a little over 11 hours of total integration time. I took it over four nights because of weather conditions.” Thank you, Catherine!
Large, pinkish, spiral-shaped object with thousands of foreground stars.
View at EarthSky Community Photos. | Jeremy Likness in Newport, Oregon, captured this telescopic view of the Andromeda galaxy on September 10, 2026. Jeremy wrote: “The numbers are mind-numbing. 2.5 million light years? One trillion stars? This week had a run of clear, dark skies. Though I’m not in a position to travel from our Newport home, the garage roof was just fine to capture my target: M31, the Andromeda galaxy. Our nearest galactic neighbor is also enthusiastically approaching us at a rate of 250,000 miles per hour, on track to collide after the estimated billion years it will take to cross the estimated 250 million light years between our galaxies. And this is the busy neighborhood!” Thank you, Jeremy!

Galaxy NGC 7331 with supernova 2026aaiv

Large, yellowish galaxy, a spiral seen almost edge-on, with white tick marks and numerous foreground stars.
View at EarthSky Community Photos. | Ernest Jacobs in North Java, New York, captured this telescopic view of galaxy NGC 7331 with supernova 2026aaiv on September 11, 2026. Ernest wrote: “This data was captured on Friday 9/11/2026 at our club’s observatory following our September member meeting. This is my processing of the data. SN2026aaiv was discovered in NGC 7331 on 9/1/2026. It is a Type Ia supernova. There was another Type Ia supernova in NGC 7331 discovered last July. NGC 7331 is in the constellation Pegasus and is about 45 million light-years from Earth. NGC 7331 is the most prominent galaxy in the NGC 7331 Group (a.k.a. The Deer Lick Group). The smaller galaxies surrounding it are sometimes referred to as The Fleas.” Thank you, Ernest!
Large, yewllowish galaxy, a spiral seen almost edge-on, with a black arrow and numerous foreground stars.
View at EarthSky Community Photos. | Dominique Gering in Belgium captured this telescopic view of galaxy NGC 7331 with supernova 2026aaiv on September 10, 2026. Dominique wrote: “Here is a galaxy that closely resembles our own (the Milky Way) in both shape and size. Located in the constellation Pegasus, NGC 7331 (its nickname) exhibits different activity; specifically, supernovae explosions occur there more frequently than in our own galaxy. A supernova marks the end of a star more massive than our sun. In this particular case, it is the thermonuclear explosion of a white dwarf that is accreting material stripped from a neighboring star. The bright star (named SN 2026aaiv) visible near the core appeared suddenly on September 1st. It will shine for a few weeks or months before “fading out.” Supernova explosions were also observed there last year, as well as in 2014, 2013, and 1959. The galaxy lies approximately 45 million light-years away from us.” Thank you, Dominique!
Large, yewllowish galaxy, a spiral seen almost edge-on, with white tick marks and numerous foreground stars.
View at EarthSky Community Photos. | Steven Bellavia in Smithfield, Virginia, captured this telescopic view of galaxy NGC 7331 with supernova 2026aaiv on September 8, 2026. Steven wrote: “Supernova SN2026aaiv is a Type Ia supernova, in galaxy NGC 7331 discovered by ATLAS on September 1st (exploding around 44 million years ago, and the light just reaching us now). Last year’s SN2025rbs, also a type Ia supernova, was the brightest of 2025, and in the same host galaxy! That is rare. Typically galaxies can go 100 years or more between supernovae.” Thank you, Steven!
Large, yewllowish galaxy, a spiral seen almost edge-on, with a foreground of numerous stars.
View at EarthSky Community Photos. | Robert Pettengill in Lampasas, Texas captured this telescopic view of galaxy NGC 7331 with supernova 2026aaiv on September 10, 2026. Robert wrote: “NGC 7331 is the largest of the Deer Lick group of galaxies in Pegasus. On Sept 1 the ATLAS asteroid warning network detected a type 1A supernova, SN 2026 aaiv near its center. I was out at Bad Wolf Ranch, near Lampasas, Texas, imaging the Deer Lick group along with nearby Stephan’s Quintet on August 13 and September 10 when I captured this image.” Thank you, Robert!

Bottom line: Enjoy this gallery of deep-sky photos from September 2026 by our EarthSky community. If you have a great photo to share, we’d love to see it!

Share your recent Earth or sky photo at EarthSky Community Photos.

Read more: Messier objects are fuzzy patches in the night sky

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A large area of blue nebulosity with bright white stars immersed within.
View at EarthSky Community Photos. | Muhammad Alaa in Egypt used a smart telescope to capture this view of the Pleiades open cluster on September 15, 2026. Muhammad wrote: “One of the most beautiful open star clusters in the night sky, surrounded by stunning blue reflection nebulosity.” Thank you, Muhammad! See more deep-sky photos from September 2026 below.

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Thank you, EarthSky community

The EarthSky community has many talented astrophotographers who capture stunning images of the deep sky. We gathered some of our favorite deep-sky photos from September 2026 for you to enjoy. Do you have images of your own to share? You can submit them to EarthSky here. We’d love to see them and share them!

Deep-sky photos of diffuse nebulae

A huge, complex red nebula with small blue swirls and a background of thousands of faint stars.
View at EarthSky Community Photos. | Ernest Jacobs in Eden, New York, captured this telescopic view of nebulae surrounding the star WR134 on September 6, 2026. Ernest wrote: “WR 134 (also known as V1769 Cyg) is a Wolf-Rayet star—a massive, hot, and rapidly shedding stellar core in its final stages of life. It has a surface temperature of about 63,000 K and a luminosity roughly 400,000 times that of the sun. WR 134 is located in the constellation Cygnus about 6,000 light-years from Earth. This image was captured over 3 nights with my wide-field deep sky imaging rig from my backyard.” Thank you, Ernest!
A large, multicolor arc of nebulosity, with numerous stars immersed within and in the surroundings.
View at EarthSky Community Photos. | Cody Sandusky in Harrisburg, Illinois, used a smart telescope to capture a part of the Veil Nebula, in the constellation Cygnus, on September 15, 2026. Cody wrote: “NGC 6960, the Western Veil Nebula, captured over five nights (approximately 15 hours of integration time) from my back yard.” Thank you, Cody!
A large, complex, orange mass of gas with blue highlights, dark lanes and numerous foreground stars.
View at EarthSky Community Photos. | Andy Dungan near Cotopaxi, Colorado, captured this telescopic view of the Wizard Nebula, in the constellation Cepheus, on September 3, 2026. Andy wrote: “I remember taking a pic of the Wizard Nebula 2 years ago. It was basically a red blob. By using narrow-band filters I really get more information and can color it in more unique ways.” Thank you, Andy!
Two large, complex, yellowish mass of gas with blue highlights and numerous foreground stars.
View at EarthSky Community Photos. | Muhammad Alaa in Assiut, Egypt, used a smart telescope to capture this view of the Heart and Soul nebulae on September 24, 2025. Muhammad calls this image a labor of love, and wrote: “The Heart and Soul Nebulae (IC 1805 and IC 1848) are two spectacular emission nebulae located in the constellation Cassiopeia, filled with glowing hydrogen gas and intricate clouds of interstellar dust. I truly love this image. This one was a little challenging to process, especially bringing out the delicate hydrogen-alpha + oxygen III emissions while preserving the natural structure and fine details of the nebulae.” Thank you, Muhammad!

Deep-sky photos of distant galaxies

Whitish spiral galaxy seen head-on, with dark lanes and sparse foreground stars.
View at EarthSky Community Photos. | Catherine Hyde in Cambria, California, captured this telescopic view of galaxy Messier 74, in the constellation Pisces, on September 19, 2026. Catherine wrote: “This is the big, beautiful face-on spiral galaxy M74 in the constellation Pisces. This is 134 images, 300 seconds each, stacked, for a little over 11 hours of total integration time. I took it over four nights because of weather conditions.” Thank you, Catherine!
Large, pinkish, spiral-shaped object with thousands of foreground stars.
View at EarthSky Community Photos. | Jeremy Likness in Newport, Oregon, captured this telescopic view of the Andromeda galaxy on September 10, 2026. Jeremy wrote: “The numbers are mind-numbing. 2.5 million light years? One trillion stars? This week had a run of clear, dark skies. Though I’m not in a position to travel from our Newport home, the garage roof was just fine to capture my target: M31, the Andromeda galaxy. Our nearest galactic neighbor is also enthusiastically approaching us at a rate of 250,000 miles per hour, on track to collide after the estimated billion years it will take to cross the estimated 250 million light years between our galaxies. And this is the busy neighborhood!” Thank you, Jeremy!

Galaxy NGC 7331 with supernova 2026aaiv

Large, yellowish galaxy, a spiral seen almost edge-on, with white tick marks and numerous foreground stars.
View at EarthSky Community Photos. | Ernest Jacobs in North Java, New York, captured this telescopic view of galaxy NGC 7331 with supernova 2026aaiv on September 11, 2026. Ernest wrote: “This data was captured on Friday 9/11/2026 at our club’s observatory following our September member meeting. This is my processing of the data. SN2026aaiv was discovered in NGC 7331 on 9/1/2026. It is a Type Ia supernova. There was another Type Ia supernova in NGC 7331 discovered last July. NGC 7331 is in the constellation Pegasus and is about 45 million light-years from Earth. NGC 7331 is the most prominent galaxy in the NGC 7331 Group (a.k.a. The Deer Lick Group). The smaller galaxies surrounding it are sometimes referred to as The Fleas.” Thank you, Ernest!
Large, yewllowish galaxy, a spiral seen almost edge-on, with a black arrow and numerous foreground stars.
View at EarthSky Community Photos. | Dominique Gering in Belgium captured this telescopic view of galaxy NGC 7331 with supernova 2026aaiv on September 10, 2026. Dominique wrote: “Here is a galaxy that closely resembles our own (the Milky Way) in both shape and size. Located in the constellation Pegasus, NGC 7331 (its nickname) exhibits different activity; specifically, supernovae explosions occur there more frequently than in our own galaxy. A supernova marks the end of a star more massive than our sun. In this particular case, it is the thermonuclear explosion of a white dwarf that is accreting material stripped from a neighboring star. The bright star (named SN 2026aaiv) visible near the core appeared suddenly on September 1st. It will shine for a few weeks or months before “fading out.” Supernova explosions were also observed there last year, as well as in 2014, 2013, and 1959. The galaxy lies approximately 45 million light-years away from us.” Thank you, Dominique!
Large, yewllowish galaxy, a spiral seen almost edge-on, with white tick marks and numerous foreground stars.
View at EarthSky Community Photos. | Steven Bellavia in Smithfield, Virginia, captured this telescopic view of galaxy NGC 7331 with supernova 2026aaiv on September 8, 2026. Steven wrote: “Supernova SN2026aaiv is a Type Ia supernova, in galaxy NGC 7331 discovered by ATLAS on September 1st (exploding around 44 million years ago, and the light just reaching us now). Last year’s SN2025rbs, also a type Ia supernova, was the brightest of 2025, and in the same host galaxy! That is rare. Typically galaxies can go 100 years or more between supernovae.” Thank you, Steven!
Large, yewllowish galaxy, a spiral seen almost edge-on, with a foreground of numerous stars.
View at EarthSky Community Photos. | Robert Pettengill in Lampasas, Texas captured this telescopic view of galaxy NGC 7331 with supernova 2026aaiv on September 10, 2026. Robert wrote: “NGC 7331 is the largest of the Deer Lick group of galaxies in Pegasus. On Sept 1 the ATLAS asteroid warning network detected a type 1A supernova, SN 2026 aaiv near its center. I was out at Bad Wolf Ranch, near Lampasas, Texas, imaging the Deer Lick group along with nearby Stephan’s Quintet on August 13 and September 10 when I captured this image.” Thank you, Robert!

Bottom line: Enjoy this gallery of deep-sky photos from September 2026 by our EarthSky community. If you have a great photo to share, we’d love to see it!

Share your recent Earth or sky photo at EarthSky Community Photos.

Read more: Messier objects are fuzzy patches in the night sky

The post Best deep-sky photos of September 2026 from EarthSky community first appeared on EarthSky.



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Proxima Centauri is the closest star to our sun


The star Proxima Centauri is the closest star to our sun, at 4.2 light-years away. It’s one of 3 stars in the Alpha Centauri system. Watch this video for more information.

Proxima Centauri is a red dwarf

The star Proxima Centauri isn’t visible to the eye. Yet it’s one of the most noted stars in the heavens. That’s because it’s part of the Alpha Centauri system, the closest star system to our sun. Alpha Centauri consists of three known stars (including Proxima). Of the three, Proxima is closest, at 4.2 light-years away. Alpha Centauri appears as the 3rd-brightest star in Earth’s sky. But Proxima is too faint to see with the eye. It’s a small, dim, low-mass star, with its own planetary system.

So, Proxima Centauri has three confirmed planets, known as Proxima Centauri b, c and d. These three exoplanets are the nearest planets outside our solar system. Proxima is a red dwarf star. And, like other red dwarfs, it’s also known to have massive solar flares.

Usually, when stars are so close to Earth, they appear bright in our sky. Consider the star Sirius, for example, in the constellation Canis Major. Sirius is the brightest star in Earth’s sky, at just 8.6 light-years away. So why isn’t Proxima Centauri, at 4.22 light years away, even brighter?

Far from being bright, Proxima is exceedingly dim. It shines at about +11 magnitude.

And that’s the nature of red dwarf stars like Proxima. These stars – the most common sorts of stars in our Milky Way galaxy – are too puny to shine brightly. Indeed, Proxima contains only about an eighth of the mass of our sun. Faint red Proxima Centauri is only 3,100 Kelvin (5,100 degrees F or 2,800 C) in contrast to 5,778 Kelvin (9,940 degrees F or 5,504 degrees C) for our sun.

So, in visible light, Proxima Centauri is only 0.0056% as luminous as our sun.

Chart with rings around sun at 2, 4, and 6 light-years with labeled stars.
Our sun’s closest neighbors, including Proxima Centauri. Image via NASA PhotoJournal.

Proxima’s location, seen from Earth

In Earth’s sky, Proxima is located in the direction of our constellation Centaurus the Centaur. That’s a southern constellation, best seen from Earth’s Southern Hemisphere. And indeed – although it can be glimpsed from very southerly latitudes in the Northern Hemisphere – many experienced northern stargazers say they’ve never seen Alpha Centauri.

Proxima lies nearly a fifth of a light-year from Alpha Centauri A and B. Because it’s so far from the two primary stars, some scientists question whether it’s really part of the star system. As an illustration, the charts below will give you a sense of Proxima’s location with respect to our sun and other stars, and with respect to Alpha Centauri A and B.

All of these nearby stars – Proxima, Alpha Centauri A and B, and our sun – orbit together around the center of our Milky Way galaxy.

Read more: Where is Proxima Centauri?

Flat, blue grid with sun in center and labeled stars above and below it.
View larger. Stars within 12 light-years of our sun. The lines on the grid are 4 light-years apart. Imaginary stalks from the plane to the stars show how far north or south they are. Proxima Centauri is part of the triple star system we see as the single star Alpha Centauri. Diagram published originally by Guy Ottewell. Used with permission. Guy commented: “It’s quite vivid when it fills the screen.”
Chart showing distance to the Alpha Centauri system from the sun. There are 3 circles around the sun for 2, 4, and 6 light-years. The system is between 4 and 6 light-years.
Another 2-dimensional chart showing the distance to the Alpha Centauri system – including Proxima Centauri – in light-years. Image via ESO.

Planets orbiting Proxima

In 2016, the European Southern Observatory (ESO) announced the discovery of Proxima b, a planet orbiting Proxima Centauri at a distance of roughly 4.7 million miles (7.5 million km) with an orbital period of approximately 11.2 Earth days. Its estimated mass is at least 1.3 times that of the Earth.

Proxima b is within the habitable zone of its star. But a 2017 study suggests that the exoplanet does not have an Earth-like atmosphere.

In June 2020, scientists announced that they had discovered a second planet candidate around the star, Proxima c. This second planet for Proxima is a lot larger than Earth and orbits its star every 1,907 days. It orbits at about 1.5 times the distance from its star than Earth orbits from the sun.

Then in 2022, the discovery of a third planet candidate orbiting Proxima Centauri was announced. Researchers used the European Southern Observatory’s Very Large Telescope (VLT). The planet, Proxima d, is only 1/4 the mass of Earth and one of the smallest and lightest exoplanets ever discovered. It orbits close to its star, at a distance of approximately 2.5 million miles (4 million kilometers). And it completes one orbit in only five days. Proxima d was confirmed by ESO’s Near Infra Red Planet Searcher (NIRPS) in 2025.

By the way, any planets around Proxima Centauri would contend with massive flares that pop off the red dwarf, which might or might not spell doom.

Proxima Centauri: Brilliant star with 4 rays and a few smaller stars scattered around.
Hubble Space Telescope image of Proxima Centauri, the closest known star to the sun. Image via ESA/ Hubble/ NASA.

Record-breaking flare on Proxima Centauri

Astronomers said in April 2021 that they spotted a flare – or burst of radiation – from Proxima that’s 100 times more powerful than any flare seen from our sun. They said the flare ranks as one of the most violent seen on a solitary star anywhere in the galaxy. Flares like this on Proxima could doom chances for life on its planets.

Astronomer R. O. Parke Loyd of Arizona State University said the verdict for life could go either way. On the one hand, the flares will eventually decimate a planet’s atmosphere. But on the other hand, flares could spark life.

In fact, Proxima Centauri appears to have frequent flares. According to NASA:

The star known as Proxima Centauri, the sun’s nearest interstellar neighbor, turns out to have a hair-trigger temper, frequently erupting with potentially damaging stellar flares, including its largest ever recorded.

A signal from our nearest neighbor?

Many scientists engaged in the Search for Extraterrestrial Intelligence (SETI) consider the famous Wow! signal to be the best-known candidate for an alien radio signal. The 1977 Wow! signal was heard only once. It was never fully confirmed and remains unexplained to this day. But in 2020 scientists found a new possible signal, dubbed by some as Wow! signal 2020. And it appeared to come from our nearest neighbor, Proxima Centauri.

However, it turned out to be from another planet, our own Earth. The source was eventually pinpointed to originate from somewhere in Australia.

Starfield with 2 yellow circles at top left for A and B, and an arrow pointing to an almost-not-visible Proxima at bottom right.
Alpha Centauri A and B are a double-star system, and a 3rd star, Proxima – whose location with respect to the other 2 is indicated by an arrow – is believed to be gravitationally bound to them. Proxima is the closest star to Earth. Image via ESO.

Bottom line: Proxima Centauri is the nearest star to our sun at 4.22 light-years away. It’s home to at least three planets and has massive solar flares.

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What Proxima’s massive flare means for our chances of alien neighbors

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The star Proxima Centauri is the closest star to our sun, at 4.2 light-years away. It’s one of 3 stars in the Alpha Centauri system. Watch this video for more information.

Proxima Centauri is a red dwarf

The star Proxima Centauri isn’t visible to the eye. Yet it’s one of the most noted stars in the heavens. That’s because it’s part of the Alpha Centauri system, the closest star system to our sun. Alpha Centauri consists of three known stars (including Proxima). Of the three, Proxima is closest, at 4.2 light-years away. Alpha Centauri appears as the 3rd-brightest star in Earth’s sky. But Proxima is too faint to see with the eye. It’s a small, dim, low-mass star, with its own planetary system.

So, Proxima Centauri has three confirmed planets, known as Proxima Centauri b, c and d. These three exoplanets are the nearest planets outside our solar system. Proxima is a red dwarf star. And, like other red dwarfs, it’s also known to have massive solar flares.

Usually, when stars are so close to Earth, they appear bright in our sky. Consider the star Sirius, for example, in the constellation Canis Major. Sirius is the brightest star in Earth’s sky, at just 8.6 light-years away. So why isn’t Proxima Centauri, at 4.22 light years away, even brighter?

Far from being bright, Proxima is exceedingly dim. It shines at about +11 magnitude.

And that’s the nature of red dwarf stars like Proxima. These stars – the most common sorts of stars in our Milky Way galaxy – are too puny to shine brightly. Indeed, Proxima contains only about an eighth of the mass of our sun. Faint red Proxima Centauri is only 3,100 Kelvin (5,100 degrees F or 2,800 C) in contrast to 5,778 Kelvin (9,940 degrees F or 5,504 degrees C) for our sun.

So, in visible light, Proxima Centauri is only 0.0056% as luminous as our sun.

Chart with rings around sun at 2, 4, and 6 light-years with labeled stars.
Our sun’s closest neighbors, including Proxima Centauri. Image via NASA PhotoJournal.

Proxima’s location, seen from Earth

In Earth’s sky, Proxima is located in the direction of our constellation Centaurus the Centaur. That’s a southern constellation, best seen from Earth’s Southern Hemisphere. And indeed – although it can be glimpsed from very southerly latitudes in the Northern Hemisphere – many experienced northern stargazers say they’ve never seen Alpha Centauri.

Proxima lies nearly a fifth of a light-year from Alpha Centauri A and B. Because it’s so far from the two primary stars, some scientists question whether it’s really part of the star system. As an illustration, the charts below will give you a sense of Proxima’s location with respect to our sun and other stars, and with respect to Alpha Centauri A and B.

All of these nearby stars – Proxima, Alpha Centauri A and B, and our sun – orbit together around the center of our Milky Way galaxy.

Read more: Where is Proxima Centauri?

Flat, blue grid with sun in center and labeled stars above and below it.
View larger. Stars within 12 light-years of our sun. The lines on the grid are 4 light-years apart. Imaginary stalks from the plane to the stars show how far north or south they are. Proxima Centauri is part of the triple star system we see as the single star Alpha Centauri. Diagram published originally by Guy Ottewell. Used with permission. Guy commented: “It’s quite vivid when it fills the screen.”
Chart showing distance to the Alpha Centauri system from the sun. There are 3 circles around the sun for 2, 4, and 6 light-years. The system is between 4 and 6 light-years.
Another 2-dimensional chart showing the distance to the Alpha Centauri system – including Proxima Centauri – in light-years. Image via ESO.

Planets orbiting Proxima

In 2016, the European Southern Observatory (ESO) announced the discovery of Proxima b, a planet orbiting Proxima Centauri at a distance of roughly 4.7 million miles (7.5 million km) with an orbital period of approximately 11.2 Earth days. Its estimated mass is at least 1.3 times that of the Earth.

Proxima b is within the habitable zone of its star. But a 2017 study suggests that the exoplanet does not have an Earth-like atmosphere.

In June 2020, scientists announced that they had discovered a second planet candidate around the star, Proxima c. This second planet for Proxima is a lot larger than Earth and orbits its star every 1,907 days. It orbits at about 1.5 times the distance from its star than Earth orbits from the sun.

Then in 2022, the discovery of a third planet candidate orbiting Proxima Centauri was announced. Researchers used the European Southern Observatory’s Very Large Telescope (VLT). The planet, Proxima d, is only 1/4 the mass of Earth and one of the smallest and lightest exoplanets ever discovered. It orbits close to its star, at a distance of approximately 2.5 million miles (4 million kilometers). And it completes one orbit in only five days. Proxima d was confirmed by ESO’s Near Infra Red Planet Searcher (NIRPS) in 2025.

By the way, any planets around Proxima Centauri would contend with massive flares that pop off the red dwarf, which might or might not spell doom.

Proxima Centauri: Brilliant star with 4 rays and a few smaller stars scattered around.
Hubble Space Telescope image of Proxima Centauri, the closest known star to the sun. Image via ESA/ Hubble/ NASA.

Record-breaking flare on Proxima Centauri

Astronomers said in April 2021 that they spotted a flare – or burst of radiation – from Proxima that’s 100 times more powerful than any flare seen from our sun. They said the flare ranks as one of the most violent seen on a solitary star anywhere in the galaxy. Flares like this on Proxima could doom chances for life on its planets.

Astronomer R. O. Parke Loyd of Arizona State University said the verdict for life could go either way. On the one hand, the flares will eventually decimate a planet’s atmosphere. But on the other hand, flares could spark life.

In fact, Proxima Centauri appears to have frequent flares. According to NASA:

The star known as Proxima Centauri, the sun’s nearest interstellar neighbor, turns out to have a hair-trigger temper, frequently erupting with potentially damaging stellar flares, including its largest ever recorded.

A signal from our nearest neighbor?

Many scientists engaged in the Search for Extraterrestrial Intelligence (SETI) consider the famous Wow! signal to be the best-known candidate for an alien radio signal. The 1977 Wow! signal was heard only once. It was never fully confirmed and remains unexplained to this day. But in 2020 scientists found a new possible signal, dubbed by some as Wow! signal 2020. And it appeared to come from our nearest neighbor, Proxima Centauri.

However, it turned out to be from another planet, our own Earth. The source was eventually pinpointed to originate from somewhere in Australia.

Starfield with 2 yellow circles at top left for A and B, and an arrow pointing to an almost-not-visible Proxima at bottom right.
Alpha Centauri A and B are a double-star system, and a 3rd star, Proxima – whose location with respect to the other 2 is indicated by an arrow – is believed to be gravitationally bound to them. Proxima is the closest star to Earth. Image via ESO.

Bottom line: Proxima Centauri is the nearest star to our sun at 4.22 light-years away. It’s home to at least three planets and has massive solar flares.

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What Proxima’s massive flare means for our chances of alien neighbors

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NASA’s Perseverance rover on Mars sets off-world driving record

The Mars Perseverance rover has set a new distance record on Mars. Watch its winding path across Mars in this animation, which shows its route from time of its 2021 landing to October 11, 2026. Video via NASA/ JPL-Caltech.

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Congratulations, Perseverance rover!

As of October 11, 2026, NASA’s Perseverance rover has driven 28.10 miles (45.22 km) on Mars. That’s a new off-world driving record for total distance driven by any vehicle on the surface of another world. The previous record of 28.06 miles (45.16 kilometers) was held by NASA’s Opportunity rover. Perseverance reached that mark on the 2,006th Martian day, or sol, of its mission. NASA said;

It covered in five and a half years a distance that took Opportunity almost 15.

The six-wheeled geologist has in less than six years surpassed a mark set by the agency’s Opportunity rover, which explored the Red Planet for nearly 15 years.

The milestone came as Perseverance traveled toward an area called Idubi through the region off the western rim of Jezero Crater nicknamed Lac de Charmes. There, the rover is investigating what may be some of the oldest terrain ever explored in the solar system.

The rocks and terrain of Lac de Charmes are so ancient that their Earthly equivalents have long since been erased by erosion and plate tectonics. But Mars doesn’t have tectonic plates. And Idubi is where the science team hopes to find traces of ancient hydrothermal (heated water) systems.

Humans set goals, Perseverance self-drives

Much of the credit belongs to Perseverance’s self-driving capability, NASA said. Using an autonomous navigation system known as AutoNav, the rover images the terrain while rolling, builds a 3D map of hazards, and plots its course between waypoints selected by rover planners on Earth — a capability the team calls thinking while driving.

Perseverance can do all that at or near its top speed, covering as much as 1,351 feet (412 meters) in a single sol.

The six-wheeled scientist has driven more than 90% of its total distance using AutoNav to evaluate the terrain. That’s in contrast to about 5% for the first Martian AutoNav system on Opportunity and its twin, Spirit. Where NASA’s first Mars rover, Sojourner, assessed the path ahead using 20 measurement points, Perseverance processes 600,000 with every look.

Steven Lee, the project manager of the Curiosity and Perseverance rovers at NASA’s Jet Propulsion Laboratory in Southern California, said:

It is an honor to be working on Perseverance at a moment when the technology has evolved to the point that drives like these are routine. The original mission called for no more than 12.4 miles of driving. We’ve blown well past that, and with all mobility systems fully operational and favorable extended-ground-life test results, we expect Perseverance to keep adding to this record for many years to come.

NASA recently approved the mission’s first extension, which began in October and will carry Perseverance’s exploration of the crater rim through roughly the end of 2028.

Perseverance rover: A portion of Martian terrain.
One of Perseverance’s navigation cameras captured this shot on October 11, 2026, the Martian day, or sol, that a 299.6-foot (91.31-meter) drive pushed the rover’s total mileage past Opportunity’s 28.06-mile (45.16-km) record on Mars. Image via NASA/JPL-Caltech.

3 decades of Mars rovers

Perseverance’s record caps nearly three decades of NASA rover operations on Mars, each mission driving farther and more capably than the last.

The microwave-oven-size Sojourner rover covered about 330 feet (100 meters) during its 83-sol mission in 1997. The golf-cart-size twins Spirit and Opportunity arrived in 2004 with 90-sol prime missions. Spirit logged 4.8 miles (7.7 km) before succumbing to the Martian winter in 2010. Opportunity kept rolling for 5,111 sols, completing the first extraterrestrial marathon in 2015 and setting the record Perseverance has now surpassed. The agency’s Curiosity rover, which landed in Gale Crater in 2012 and remains hard at work, has logged more than 23.65 miles (38.07 kilometers).

Mark Maimone, deputy team chief for robotic operations on Perseverance, said:

The rover that broke this record did so by making its own decisions about the path. Given the autonomy to just go, Perseverance is a better driver than the one that landed, and we’re not done,

Our newest software teaches Perseverance to steer less and roll more, and to check its own position against orbital maps mid-drive.

The next frontier is sunlight itself. Glare in the navigation cameras is why we park by mid-afternoon if we’re driving toward the sun, and if we can teach the rover to see past those artifacts, every rover that follows gets a longer working day.

Not just Mars, and why it matters

The extraterrestrial off-road driving record isn’t limited to Mars: Lunar driving records were broken earlier in the journey. Perseverance rolled past both the 22.2 miles (35.7 kilometers) covered by Apollo 17 astronauts Gene Cernan and Harrison Schmitt in 1972 and the 24.2 miles (39 kilometers) driven by the Soviet Union’s Lunokhod 2 rover in 1973.

Setting distance records is just a bonus. Stamina and longer drives are putting more geologic diversity within reach faster — more outcrops examined and more of the Red Planet’s history read from its rocks. That reach carried Perseverance from an ancient lakebed up a fossilized river system, where the rover found a potential biosignature at a rock called Cheyava Falls, and on to the crater rim, where an entirely different kind of ancient habitat — hydrothermal (heated water) — may await.

Perseverance has collected 29 rock and regolith samples. The samples span the crater floor, a delta fan formed by a long-gone river, and now the crater rim. In the latter region, it has been exploring impact-generated rocks some 4 billion years old. On Earth, that chapter of planetary history has been almost entirely erased.

After Lac de Charmes, the rover will continue along the crater rim and head south during the extended mission towards Rainbow Falls, a 328-foot-wide (100-meter-wide) block of ancient crust uplifted by the impact that created Jezero.

Infographic showing various driving distances accomplished by Mars and moon rovers.
This infographic illustrates the distances driven by various rovers on the surface of Earth’s Moon and Mars. Of the vehicles shown, the NASA Mars rovers Perseverance and Curiosity are still operational and moving across the surface; the figures shown for those two are distances driven as of Oct. 11, 2026. Credit: NASA/JPL-Caltech.

Bottom line: The Mars Perseverance rover has set a new distance record on Mars. It has driven 28.10 miles (45.22 km). Perseverance reached that mark on October 11, 2026, the 2,006th Martian day, or sol, of its mission.

Read more: Perseverance rover takes its 6th-ever selfie on Mars

Read more: Curiosity rover insights after 5000+ sols on Mars

The post NASA’s Perseverance rover on Mars sets off-world driving record first appeared on EarthSky.



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The Mars Perseverance rover has set a new distance record on Mars. Watch its winding path across Mars in this animation, which shows its route from time of its 2021 landing to October 11, 2026. Video via NASA/ JPL-Caltech.

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Congratulations, Perseverance rover!

As of October 11, 2026, NASA’s Perseverance rover has driven 28.10 miles (45.22 km) on Mars. That’s a new off-world driving record for total distance driven by any vehicle on the surface of another world. The previous record of 28.06 miles (45.16 kilometers) was held by NASA’s Opportunity rover. Perseverance reached that mark on the 2,006th Martian day, or sol, of its mission. NASA said;

It covered in five and a half years a distance that took Opportunity almost 15.

The six-wheeled geologist has in less than six years surpassed a mark set by the agency’s Opportunity rover, which explored the Red Planet for nearly 15 years.

The milestone came as Perseverance traveled toward an area called Idubi through the region off the western rim of Jezero Crater nicknamed Lac de Charmes. There, the rover is investigating what may be some of the oldest terrain ever explored in the solar system.

The rocks and terrain of Lac de Charmes are so ancient that their Earthly equivalents have long since been erased by erosion and plate tectonics. But Mars doesn’t have tectonic plates. And Idubi is where the science team hopes to find traces of ancient hydrothermal (heated water) systems.

Humans set goals, Perseverance self-drives

Much of the credit belongs to Perseverance’s self-driving capability, NASA said. Using an autonomous navigation system known as AutoNav, the rover images the terrain while rolling, builds a 3D map of hazards, and plots its course between waypoints selected by rover planners on Earth — a capability the team calls thinking while driving.

Perseverance can do all that at or near its top speed, covering as much as 1,351 feet (412 meters) in a single sol.

The six-wheeled scientist has driven more than 90% of its total distance using AutoNav to evaluate the terrain. That’s in contrast to about 5% for the first Martian AutoNav system on Opportunity and its twin, Spirit. Where NASA’s first Mars rover, Sojourner, assessed the path ahead using 20 measurement points, Perseverance processes 600,000 with every look.

Steven Lee, the project manager of the Curiosity and Perseverance rovers at NASA’s Jet Propulsion Laboratory in Southern California, said:

It is an honor to be working on Perseverance at a moment when the technology has evolved to the point that drives like these are routine. The original mission called for no more than 12.4 miles of driving. We’ve blown well past that, and with all mobility systems fully operational and favorable extended-ground-life test results, we expect Perseverance to keep adding to this record for many years to come.

NASA recently approved the mission’s first extension, which began in October and will carry Perseverance’s exploration of the crater rim through roughly the end of 2028.

Perseverance rover: A portion of Martian terrain.
One of Perseverance’s navigation cameras captured this shot on October 11, 2026, the Martian day, or sol, that a 299.6-foot (91.31-meter) drive pushed the rover’s total mileage past Opportunity’s 28.06-mile (45.16-km) record on Mars. Image via NASA/JPL-Caltech.

3 decades of Mars rovers

Perseverance’s record caps nearly three decades of NASA rover operations on Mars, each mission driving farther and more capably than the last.

The microwave-oven-size Sojourner rover covered about 330 feet (100 meters) during its 83-sol mission in 1997. The golf-cart-size twins Spirit and Opportunity arrived in 2004 with 90-sol prime missions. Spirit logged 4.8 miles (7.7 km) before succumbing to the Martian winter in 2010. Opportunity kept rolling for 5,111 sols, completing the first extraterrestrial marathon in 2015 and setting the record Perseverance has now surpassed. The agency’s Curiosity rover, which landed in Gale Crater in 2012 and remains hard at work, has logged more than 23.65 miles (38.07 kilometers).

Mark Maimone, deputy team chief for robotic operations on Perseverance, said:

The rover that broke this record did so by making its own decisions about the path. Given the autonomy to just go, Perseverance is a better driver than the one that landed, and we’re not done,

Our newest software teaches Perseverance to steer less and roll more, and to check its own position against orbital maps mid-drive.

The next frontier is sunlight itself. Glare in the navigation cameras is why we park by mid-afternoon if we’re driving toward the sun, and if we can teach the rover to see past those artifacts, every rover that follows gets a longer working day.

Not just Mars, and why it matters

The extraterrestrial off-road driving record isn’t limited to Mars: Lunar driving records were broken earlier in the journey. Perseverance rolled past both the 22.2 miles (35.7 kilometers) covered by Apollo 17 astronauts Gene Cernan and Harrison Schmitt in 1972 and the 24.2 miles (39 kilometers) driven by the Soviet Union’s Lunokhod 2 rover in 1973.

Setting distance records is just a bonus. Stamina and longer drives are putting more geologic diversity within reach faster — more outcrops examined and more of the Red Planet’s history read from its rocks. That reach carried Perseverance from an ancient lakebed up a fossilized river system, where the rover found a potential biosignature at a rock called Cheyava Falls, and on to the crater rim, where an entirely different kind of ancient habitat — hydrothermal (heated water) — may await.

Perseverance has collected 29 rock and regolith samples. The samples span the crater floor, a delta fan formed by a long-gone river, and now the crater rim. In the latter region, it has been exploring impact-generated rocks some 4 billion years old. On Earth, that chapter of planetary history has been almost entirely erased.

After Lac de Charmes, the rover will continue along the crater rim and head south during the extended mission towards Rainbow Falls, a 328-foot-wide (100-meter-wide) block of ancient crust uplifted by the impact that created Jezero.

Infographic showing various driving distances accomplished by Mars and moon rovers.
This infographic illustrates the distances driven by various rovers on the surface of Earth’s Moon and Mars. Of the vehicles shown, the NASA Mars rovers Perseverance and Curiosity are still operational and moving across the surface; the figures shown for those two are distances driven as of Oct. 11, 2026. Credit: NASA/JPL-Caltech.

Bottom line: The Mars Perseverance rover has set a new distance record on Mars. It has driven 28.10 miles (45.22 km). Perseverance reached that mark on October 11, 2026, the 2,006th Martian day, or sol, of its mission.

Read more: Perseverance rover takes its 6th-ever selfie on Mars

Read more: Curiosity rover insights after 5000+ sols on Mars

The post NASA’s Perseverance rover on Mars sets off-world driving record first appeared on EarthSky.



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Meet Aquarius the Water Bearer and its stars

Aquarius: Star chart with 13 white dots connected by blue lines on dark blue background.
Aquarius the Water Bearer is a constellation of the zodiac that contains mostly dim stars. You can see it best on a fall evening in the Northern Hemisphere or a spring evening in the Southern Hemisphere. Chart via EarthSky.

Lying on our sky’s dome between the constellations Capricornus and Pisces, Aquarius the Water Bearer is tricky to spot. There aren’t many bright stars in this constellation, and you’ll need a dark sky to get a good look at it.

It’s one of the 13 constellations of the zodiac, which means the sun, moon and planets occasionally pass within its boundaries.

When to see Aquarius

The best time to spot Aquarius is in the evening during a Northern Hemisphere autumn or Southern Hemisphere spring. Aquarius is just east of another zodiacal constellation, Capricornus.

And you can use the Great Square of Pegasus to guide you toward Aquarius.

From northerly latitudes, this constellation appears in the southern sky. South of the equator, it’s found overhead or high in the northern sky. You’ll see Aquarius highest in the sky in early October around 10 p.m. local time (11 p.m. local daylight saving time in the U.S.). Or try one month later – in early November – around 8 p.m. local time (9 p.m. local daylight saving time in the U.S.).

A sea in the sky

Aquarius lies in a region of the sky sometimes called the Sea. This part of the sky looks dark and deep, but of course there are stars here, as there are everywhere on the heavenly globe. The stars in this part of the sky tend to be faint. In western sky lore, early stargazers associated the star patterns here with water in a celestial sea.

It’s here we find Cetus the Whale, Pisces the Fish, Eridanus the River, and Piscis Austrinus the Southern Fish.

The brightest star in this “watery” region of the sky is Fomalhaut in Piscis Austrinus the Southern Fish. Aquarius the Water Bearer is usually portrayed as a man pouring a stream of water into the mouth of the Southern Fish, which is interesting since fish don’t drink water. In the sky, you’ll see a zigzag line of stars leading from Aquarius to Fomalhaut, the only bright star in the Celestial Sea. By the way, because it’s in such an apparently empty part of the sky, Fomalhaut is sometimes called the Loneliest Star.

The stars of Aquarius

The two brightest stars in Aquarius are the magnitude 2.9 Beta Aquarii, or Sadalsuud, and the magnitude 2.95 Alpha Aquarii, or Sadalmelik. The two stars are 10 degrees apart, or about the width of your fist held at arm’s length.

The next brightest star is magnitude 3.27 Delta Aquarii, or Skat. A triple star (visual only, not physically related) is the stars of Psi Aquarii. Their magnitudes range from 4.2 to 4.9.

If your sky is dark enough, you can see a little asterism – or noticeable pattern of stars within Aquarius – just to the left of the star Sadalmelik. This little pattern, shown within the orange dashed oval in the star map, is called the Water Jar in Aquarius. Imagine a cascade of faint stars as water, visible in very dark skies, making a zigzag stream of stars, flowing down toward Fomalhaut.

Star chart of Aquarius with stars in black on white with a dashed orange oval around four stars.
A map of the constellation Aquarius. The orange dashed oval region is the Water Jar asterism. You can imagine stars pouring out from the Water Jar into the open mouth of Piscis Austrinus. Image via IAU.

Deep-sky treasures in Aquarius

Aquarius is home to a number of Messier objects, including both clusters and nebulae.

The globular cluster M2 resides in Aquarius. M2 is above a line drawn between the Alpha and Beta stars. This globular cluster shines at magnitude 6.5 and lies about 37,000 light-years away.

M72 is another globular cluster that can be found in Aquarius. If you draw a line from Alpha, through Beta, and extend it 11 to 12 degrees forward, you’ll run into M72. While you can see M2 with binoculars, M72 is magnitude 9.4, so you’ll need a telescope. M72 lies 55,000 light-years away.

An open cluster in the same area as M72 is M73, just over 1 degree east from the globular cluster. It shines a bit brighter at magnitude 9 but is a smaller and less noticeable grouping of stars.

Close to M72 and M73 is the Saturn Nebula, or NGC 7009. This 8th-magnitude planetary nebula looks like the planet Saturn because its gassy halo includes a thin extension on both sides that look like rings.

Another well-known nebula, the Helix Nebula (NGC 7293) lies in Aquarius. The Helix lies about 20 degrees below the stars Alpha and Beta. Although the Helix is magnitude 7.3, it’s hard to observe because its light extends over a large space. This nebula spreads out across 28 arcminutes, almost as large as a full moon. However, its appearance in photographs is quite stunning.

Aquarius in history and star lore

Aquarius is tied to an abundance of water, sometimes as a blessing and sometimes as a curse.

Greek mythology associates Aquarius with the deluge that wiped out all of humanity except for Deucalion and his wife Pyrrha. Zeus, king of the gods, unleashed the flood to punish people for their misdeeds. But Zeus advised the virtuous Deucalion to save himself by building an ark. This tale of divine retribution strongly parallels the story of the great flood in the Old Testament.

In ancient Egypt, the constellation Aquarius represented Hapi, god of the Nile River. This benevolent god distributed the waters of life, and the urn symbolized a fount of good fortune. It’s this association that explains why the Water Bearer is often seen holding the Norma Nilotica, a rod for measuring the depth of the Nile River. Also, the names of Aquarius’ two brightest stars – Sadalmelik and Sadalsuud – reaffirm the idea of providence. The names are thought to mean lucky one of the king and luckiest of the lucky.

Colored etching of old bearded man holding a large ceramic jar tipped down with water flowing out.
An illustration of Aquarius the Water Bearer from Urania’s Mirror, a set of astronomical star charts first published in 1824. Notice the Water Jar asterism. Water flows from the jar towards Fomalhaut, in the mouth of the Southern Fish. Image via U.S. Library of Congress/ Wikimedia Commons.

Dates of sun’s passage through Aquarius

As seen from Earth, the sun passes in front of the constellation Aquarius from about February 16 to March 12. It is important to note that these dates are in reference to the constellation – not the sign – Aquarius. The sun is in the sign Aquarius from about January 20 to February 18. (A constellation of the zodiac refers to certain section of the starry sky.

On the other hand, a sign of the zodiac refers to the seasonal position of the sun, irrespective of what constellation backdrops the sun at a given season.)

You’ve no doubt heard the song The Age of Aquarius. Learn more about what that phrase means here.

Bottom line: Aquarius the Water Bearer is a faint zodiacal constellation, best seen in a dark sky.

The constellations of the zodiac

Meet Taurus the Bull in the evening sky
Meet Gemini the Twins, home to 2 bright stars
Meet Cancer the Crab and its Beehive Cluster
Leo the Lion and its backward question mark
Virgo the Maiden in northern spring skies
Meet Libra the Scales, a zodiacal constellation
Scorpius the Scorpion is a summertime delight
Sagittarius the Archer and its famous Teapot
Capricornus the Sea-goat has an arrowhead shape
Meet Aquarius the Water Bearer and its stars
Meet Pisces the Fish, 1st constellation of the zodiac
Say hello to Aries the Ram
Born under the sign of Ophiuchus?

The post Meet Aquarius the Water Bearer and its stars first appeared on EarthSky.



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Aquarius: Star chart with 13 white dots connected by blue lines on dark blue background.
Aquarius the Water Bearer is a constellation of the zodiac that contains mostly dim stars. You can see it best on a fall evening in the Northern Hemisphere or a spring evening in the Southern Hemisphere. Chart via EarthSky.

Lying on our sky’s dome between the constellations Capricornus and Pisces, Aquarius the Water Bearer is tricky to spot. There aren’t many bright stars in this constellation, and you’ll need a dark sky to get a good look at it.

It’s one of the 13 constellations of the zodiac, which means the sun, moon and planets occasionally pass within its boundaries.

When to see Aquarius

The best time to spot Aquarius is in the evening during a Northern Hemisphere autumn or Southern Hemisphere spring. Aquarius is just east of another zodiacal constellation, Capricornus.

And you can use the Great Square of Pegasus to guide you toward Aquarius.

From northerly latitudes, this constellation appears in the southern sky. South of the equator, it’s found overhead or high in the northern sky. You’ll see Aquarius highest in the sky in early October around 10 p.m. local time (11 p.m. local daylight saving time in the U.S.). Or try one month later – in early November – around 8 p.m. local time (9 p.m. local daylight saving time in the U.S.).

A sea in the sky

Aquarius lies in a region of the sky sometimes called the Sea. This part of the sky looks dark and deep, but of course there are stars here, as there are everywhere on the heavenly globe. The stars in this part of the sky tend to be faint. In western sky lore, early stargazers associated the star patterns here with water in a celestial sea.

It’s here we find Cetus the Whale, Pisces the Fish, Eridanus the River, and Piscis Austrinus the Southern Fish.

The brightest star in this “watery” region of the sky is Fomalhaut in Piscis Austrinus the Southern Fish. Aquarius the Water Bearer is usually portrayed as a man pouring a stream of water into the mouth of the Southern Fish, which is interesting since fish don’t drink water. In the sky, you’ll see a zigzag line of stars leading from Aquarius to Fomalhaut, the only bright star in the Celestial Sea. By the way, because it’s in such an apparently empty part of the sky, Fomalhaut is sometimes called the Loneliest Star.

The stars of Aquarius

The two brightest stars in Aquarius are the magnitude 2.9 Beta Aquarii, or Sadalsuud, and the magnitude 2.95 Alpha Aquarii, or Sadalmelik. The two stars are 10 degrees apart, or about the width of your fist held at arm’s length.

The next brightest star is magnitude 3.27 Delta Aquarii, or Skat. A triple star (visual only, not physically related) is the stars of Psi Aquarii. Their magnitudes range from 4.2 to 4.9.

If your sky is dark enough, you can see a little asterism – or noticeable pattern of stars within Aquarius – just to the left of the star Sadalmelik. This little pattern, shown within the orange dashed oval in the star map, is called the Water Jar in Aquarius. Imagine a cascade of faint stars as water, visible in very dark skies, making a zigzag stream of stars, flowing down toward Fomalhaut.

Star chart of Aquarius with stars in black on white with a dashed orange oval around four stars.
A map of the constellation Aquarius. The orange dashed oval region is the Water Jar asterism. You can imagine stars pouring out from the Water Jar into the open mouth of Piscis Austrinus. Image via IAU.

Deep-sky treasures in Aquarius

Aquarius is home to a number of Messier objects, including both clusters and nebulae.

The globular cluster M2 resides in Aquarius. M2 is above a line drawn between the Alpha and Beta stars. This globular cluster shines at magnitude 6.5 and lies about 37,000 light-years away.

M72 is another globular cluster that can be found in Aquarius. If you draw a line from Alpha, through Beta, and extend it 11 to 12 degrees forward, you’ll run into M72. While you can see M2 with binoculars, M72 is magnitude 9.4, so you’ll need a telescope. M72 lies 55,000 light-years away.

An open cluster in the same area as M72 is M73, just over 1 degree east from the globular cluster. It shines a bit brighter at magnitude 9 but is a smaller and less noticeable grouping of stars.

Close to M72 and M73 is the Saturn Nebula, or NGC 7009. This 8th-magnitude planetary nebula looks like the planet Saturn because its gassy halo includes a thin extension on both sides that look like rings.

Another well-known nebula, the Helix Nebula (NGC 7293) lies in Aquarius. The Helix lies about 20 degrees below the stars Alpha and Beta. Although the Helix is magnitude 7.3, it’s hard to observe because its light extends over a large space. This nebula spreads out across 28 arcminutes, almost as large as a full moon. However, its appearance in photographs is quite stunning.

Aquarius in history and star lore

Aquarius is tied to an abundance of water, sometimes as a blessing and sometimes as a curse.

Greek mythology associates Aquarius with the deluge that wiped out all of humanity except for Deucalion and his wife Pyrrha. Zeus, king of the gods, unleashed the flood to punish people for their misdeeds. But Zeus advised the virtuous Deucalion to save himself by building an ark. This tale of divine retribution strongly parallels the story of the great flood in the Old Testament.

In ancient Egypt, the constellation Aquarius represented Hapi, god of the Nile River. This benevolent god distributed the waters of life, and the urn symbolized a fount of good fortune. It’s this association that explains why the Water Bearer is often seen holding the Norma Nilotica, a rod for measuring the depth of the Nile River. Also, the names of Aquarius’ two brightest stars – Sadalmelik and Sadalsuud – reaffirm the idea of providence. The names are thought to mean lucky one of the king and luckiest of the lucky.

Colored etching of old bearded man holding a large ceramic jar tipped down with water flowing out.
An illustration of Aquarius the Water Bearer from Urania’s Mirror, a set of astronomical star charts first published in 1824. Notice the Water Jar asterism. Water flows from the jar towards Fomalhaut, in the mouth of the Southern Fish. Image via U.S. Library of Congress/ Wikimedia Commons.

Dates of sun’s passage through Aquarius

As seen from Earth, the sun passes in front of the constellation Aquarius from about February 16 to March 12. It is important to note that these dates are in reference to the constellation – not the sign – Aquarius. The sun is in the sign Aquarius from about January 20 to February 18. (A constellation of the zodiac refers to certain section of the starry sky.

On the other hand, a sign of the zodiac refers to the seasonal position of the sun, irrespective of what constellation backdrops the sun at a given season.)

You’ve no doubt heard the song The Age of Aquarius. Learn more about what that phrase means here.

Bottom line: Aquarius the Water Bearer is a faint zodiacal constellation, best seen in a dark sky.

The constellations of the zodiac

Meet Taurus the Bull in the evening sky
Meet Gemini the Twins, home to 2 bright stars
Meet Cancer the Crab and its Beehive Cluster
Leo the Lion and its backward question mark
Virgo the Maiden in northern spring skies
Meet Libra the Scales, a zodiacal constellation
Scorpius the Scorpion is a summertime delight
Sagittarius the Archer and its famous Teapot
Capricornus the Sea-goat has an arrowhead shape
Meet Aquarius the Water Bearer and its stars
Meet Pisces the Fish, 1st constellation of the zodiac
Say hello to Aries the Ram
Born under the sign of Ophiuchus?

The post Meet Aquarius the Water Bearer and its stars first appeared on EarthSky.



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