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See Venus in the daytime: Here are 3 tips

Bright white dot in the sky and inset larger image of the dot, above pine tree branches.
View at EarthSky Community Photos. | Steven Bellavia captured this image on February 7, 2025, in Virginia. Steven wrote: “Venus, in broad daylight, on a beautiful clear day. A little zoom-in, and you can see the crescent shape.” Thank you, Steven! Keep reading for tips on seeing Venus in the daytime.
  • Venus is bright enough to see in daylight when the sky is clear and you know exactly where to look.
  • One way is to use the moon as a guide. Or look when Venus is highest in the sky. Or, when Venus is up before sunrise, track it after sunrise.
  • Never look at the sun with your unprotected eyes. When searching for Venus in daylight, position the sun behind a building.

Don’t miss the next spectacular sky event! Subscribe to EarthSky’s free daily newsletter for sky and science news.

Why can you see Venus in daylight?

After the sun and moon, Venus is the brightest natural object in our sky.

It appears so bright because it’s relatively close to Earth, and is nearly as large as Earth. But, most importantly, Venus is covered with highly reflective clouds. It reflects approximately 75% of the sunlight shining on it back into space.

Still, Venus can be difficult to find against a bright blue sky. You need to know its location before you begin looking. How can you know at any given time whether Venus is up in the morning or the evening? A great way is to check EarthSky’s visible planets guide. It’s updated daily and will tell you when and where Venus is currently visible.

Or use an astronomy app such as Stellarium.

Right now – September 13, 2026 — Venus is in the west after sunset. It’ll pass between the Earth and sun on October 23-24, 2026. Afterwards, it’ll return to the east before dawn. You should begin to see it before dawn in early November, 2026.

Safety warning: Never look directly at the sun. Do not use binoculars, a telescope or a camera to search for Venus in daylight. If possible, stand where a tree trunk or building completely blocks the sun.

Thin crescent Venus in a blue daytime sky with part of a statue in the foreground.
View at EarthSky Community Photos. | Paolo Palma captured this image on March 18, 2025, from Italy. To the unaided eye, Venus looks like a point of light. But magnified photographs can reveal its changing phases. Around the time the planet is passing between Earth and the sun, it’ll appear as a slim crescent in our sky. Venus will go between us and the sun next on October 23-24, 2026.

Tip #1 for seeing Venus in daylight: Use the moon

Venus is bright enough to appear as a tiny white point in a blue daytime sky. The easiest way to find it — when Venus is in the evening sky, as it is now – is to use the moon as a guide.

Then, on a clear sunny day, find the moon first with your unaided eyes. And use the app to determine which direction Venus lies from the moon and how far apart they appear. Venus will look like a tiny white point.

Remember to keep the sun hidden behind a building.

A crescent shape, the moon, moves past a starred dot, Venus. They are above a wavy line, the horizon.
Shortly after sunset on September 13 and 14, the thin waxing moon will sweep past brilliant Venus. And Venus is at its greatest brilliancy this week! Be sure to step outside for this sweet sky scene. The farther south you are on Earth’s globe, the higher Venus will appear in your sky after sunset. The moon will occult, or pass in front of, Venus in daylight for people in Europe and Africa at 11 UTC on September 14. Few people (or nobody) will see the occultation. But many will see the moon exceptionally near Venus in the evening sky. The Southern Hemisphere has the best view! Read about the occultation here. Chart via EarthSky.

Tip #2: Look for Venus high in the sky

On days when Venus is above your horizon in daylight, it reaches its highest point in the sky as it crosses your local meridian (an imaginery line across the sky over your head, between your sky’s due north and due south points). Astronomers call this crossing a meridian transit, or culmination, of Venus.

Venus can be easier to find around this time because — at meridian transit — it’s as high above the horizon as it will be that day.

An astronomy app can provide the time of Venus’s meridian transit, along with its altitude, or height above your horizon. It’ll also give you the compass direction of Venus. That direction varies with your location, the season and the time of day. So follow the app rather than assuming Venus will be due south or north.

As always, before you look, position yourself so that a solid structure blocks the sun.

Magnified view of thin crescent Venus against a blue daytime sky.
View at EarthSky Community Photos. | A magnified view of crescent Venus in daylight, captured four days before inferior conjunction. Steven Bellavia captured the image on March 18, 2025, in Virginia.

Tip #3: Track Venus after sunrise

Another way — useful when Venus comes back to the morning sky this November — is to locate Venus before sunrise and follow it as the sky brightens. Again, an astronomy app can also show you exactly where to look. But you don’t need an app. You can just watch. This is often the easiest method for finding Venus in daylight, but it only works when Venus is visible in the morning (which it will be, again, by early November 2026).

Just find the planet before sunrise, when it will be the brightest starlike object in that part of the sky. Note its position relative to a building, pole or other fixed landmark. Continue watching as the eastern sky brightens at dawn. Venus will become less obvious after sunrise, but, if you keep watching, you can keep it in view. If you look away, use your landmark to return to Venus as dawn is breaking.

Stop if the sun approaches your line of sight, and never use binoculars or a telescope to search for the planet.

Good luck!

Have you photographed Venus in daylight? Submit your image to EarthSky.

Venus in the daytime: Three diagrams showing Venus as a dot rising higher in the sky beside a tree as the sun rises.
View larger. | One way to see Venus in daylight is to find it before sunrise and follow it as the sky brightens. Note its position relative to a foreground landmark so you can find it again. Always keep the sun safely out of view. Chart via EarthSky.

Bottom line: You can see Venus in daylight when the sky is clear and you know where to look. Use the moon as a guide, track Venus through sunrise or use an astronomy app to find it when it is highest in the sky. Always keep the sun safely out of view.

Source: Venus facts from NASA

Source: Eye safety from the American Astronomical Society

Read more: Why is Venus so bright?

Read more: Top 10 space objects to see during the day

The post See Venus in the daytime: Here are 3 tips first appeared on EarthSky.



from EarthSky https://ift.tt/kuET90z
Bright white dot in the sky and inset larger image of the dot, above pine tree branches.
View at EarthSky Community Photos. | Steven Bellavia captured this image on February 7, 2025, in Virginia. Steven wrote: “Venus, in broad daylight, on a beautiful clear day. A little zoom-in, and you can see the crescent shape.” Thank you, Steven! Keep reading for tips on seeing Venus in the daytime.
  • Venus is bright enough to see in daylight when the sky is clear and you know exactly where to look.
  • One way is to use the moon as a guide. Or look when Venus is highest in the sky. Or, when Venus is up before sunrise, track it after sunrise.
  • Never look at the sun with your unprotected eyes. When searching for Venus in daylight, position the sun behind a building.

Don’t miss the next spectacular sky event! Subscribe to EarthSky’s free daily newsletter for sky and science news.

Why can you see Venus in daylight?

After the sun and moon, Venus is the brightest natural object in our sky.

It appears so bright because it’s relatively close to Earth, and is nearly as large as Earth. But, most importantly, Venus is covered with highly reflective clouds. It reflects approximately 75% of the sunlight shining on it back into space.

Still, Venus can be difficult to find against a bright blue sky. You need to know its location before you begin looking. How can you know at any given time whether Venus is up in the morning or the evening? A great way is to check EarthSky’s visible planets guide. It’s updated daily and will tell you when and where Venus is currently visible.

Or use an astronomy app such as Stellarium.

Right now – September 13, 2026 — Venus is in the west after sunset. It’ll pass between the Earth and sun on October 23-24, 2026. Afterwards, it’ll return to the east before dawn. You should begin to see it before dawn in early November, 2026.

Safety warning: Never look directly at the sun. Do not use binoculars, a telescope or a camera to search for Venus in daylight. If possible, stand where a tree trunk or building completely blocks the sun.

Thin crescent Venus in a blue daytime sky with part of a statue in the foreground.
View at EarthSky Community Photos. | Paolo Palma captured this image on March 18, 2025, from Italy. To the unaided eye, Venus looks like a point of light. But magnified photographs can reveal its changing phases. Around the time the planet is passing between Earth and the sun, it’ll appear as a slim crescent in our sky. Venus will go between us and the sun next on October 23-24, 2026.

Tip #1 for seeing Venus in daylight: Use the moon

Venus is bright enough to appear as a tiny white point in a blue daytime sky. The easiest way to find it — when Venus is in the evening sky, as it is now – is to use the moon as a guide.

Then, on a clear sunny day, find the moon first with your unaided eyes. And use the app to determine which direction Venus lies from the moon and how far apart they appear. Venus will look like a tiny white point.

Remember to keep the sun hidden behind a building.

A crescent shape, the moon, moves past a starred dot, Venus. They are above a wavy line, the horizon.
Shortly after sunset on September 13 and 14, the thin waxing moon will sweep past brilliant Venus. And Venus is at its greatest brilliancy this week! Be sure to step outside for this sweet sky scene. The farther south you are on Earth’s globe, the higher Venus will appear in your sky after sunset. The moon will occult, or pass in front of, Venus in daylight for people in Europe and Africa at 11 UTC on September 14. Few people (or nobody) will see the occultation. But many will see the moon exceptionally near Venus in the evening sky. The Southern Hemisphere has the best view! Read about the occultation here. Chart via EarthSky.

Tip #2: Look for Venus high in the sky

On days when Venus is above your horizon in daylight, it reaches its highest point in the sky as it crosses your local meridian (an imaginery line across the sky over your head, between your sky’s due north and due south points). Astronomers call this crossing a meridian transit, or culmination, of Venus.

Venus can be easier to find around this time because — at meridian transit — it’s as high above the horizon as it will be that day.

An astronomy app can provide the time of Venus’s meridian transit, along with its altitude, or height above your horizon. It’ll also give you the compass direction of Venus. That direction varies with your location, the season and the time of day. So follow the app rather than assuming Venus will be due south or north.

As always, before you look, position yourself so that a solid structure blocks the sun.

Magnified view of thin crescent Venus against a blue daytime sky.
View at EarthSky Community Photos. | A magnified view of crescent Venus in daylight, captured four days before inferior conjunction. Steven Bellavia captured the image on March 18, 2025, in Virginia.

Tip #3: Track Venus after sunrise

Another way — useful when Venus comes back to the morning sky this November — is to locate Venus before sunrise and follow it as the sky brightens. Again, an astronomy app can also show you exactly where to look. But you don’t need an app. You can just watch. This is often the easiest method for finding Venus in daylight, but it only works when Venus is visible in the morning (which it will be, again, by early November 2026).

Just find the planet before sunrise, when it will be the brightest starlike object in that part of the sky. Note its position relative to a building, pole or other fixed landmark. Continue watching as the eastern sky brightens at dawn. Venus will become less obvious after sunrise, but, if you keep watching, you can keep it in view. If you look away, use your landmark to return to Venus as dawn is breaking.

Stop if the sun approaches your line of sight, and never use binoculars or a telescope to search for the planet.

Good luck!

Have you photographed Venus in daylight? Submit your image to EarthSky.

Venus in the daytime: Three diagrams showing Venus as a dot rising higher in the sky beside a tree as the sun rises.
View larger. | One way to see Venus in daylight is to find it before sunrise and follow it as the sky brightens. Note its position relative to a foreground landmark so you can find it again. Always keep the sun safely out of view. Chart via EarthSky.

Bottom line: You can see Venus in daylight when the sky is clear and you know where to look. Use the moon as a guide, track Venus through sunrise or use an astronomy app to find it when it is highest in the sky. Always keep the sun safely out of view.

Source: Venus facts from NASA

Source: Eye safety from the American Astronomical Society

Read more: Why is Venus so bright?

Read more: Top 10 space objects to see during the day

The post See Venus in the daytime: Here are 3 tips first appeared on EarthSky.



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Crepuscular rays are sunrays in twilight skies

Crepuscular rays coming off the sun above some trees in the distance.
View at EarthSky Community Photos. | Sudhir Sharma photographed this on October 7, 2025, in India, and wrote: “While driving this afternoon we saw this amazing sunset with crepuscular rays.” Thank you, Sudhir!

What are crepuscular rays?

Crepuscular means resembling twilight or dim. This phenomenon occurs around sunrise or sunset, when the sun is below the horizon. And you can also see crepuscular rays when the sun is hiding behind clouds. They’re more noticeable when the sky is a bit darker and there is greater contrast between dark and light. We can see the rays of light thanks to dust, smoke or water droplets that scatter the light toward our eyes.

The darker streaks beside the sunrays are due to shadows, where the terrain or clouds block the sunlight from coming through. Sometimes those obstructions are below the horizon from your point of view, so it may not seem immediately clear what’s causing the darker rays.

When crepuscular rays extend from behind a cloud toward the ground, they also go by the nickname Jacob’s Ladder. The term comes from a story in the Bible where Jacob has a dream in which he sees a ladder leading up to the golden light of heaven with angels ascending and descending.

Parallel lines that seem to converge

Crepuscular rays appear to fan across the sky. But these sunrays are really parallel to each other. In fact, sometimes you can trace them all the way across the sky to the point on the horizon opposite the sunset. So, the next time you see them, remember to turn around. You might spot the fainter and less noticeable anticrepuscular rays. The illusion is similar to standing on train tracks and seeing how they appear to converge in the far distance in front of and behind you.

Black and white image showing crepuscular rays over the Sierra mountains.
View at EarthSky Community Photos. | Ross Stone captured this image on July 15, 2026, from California and wrote: “With the summer heat of the Owens valley being unbearable, an afternoon trip into the White mountains is a must to escape the heat. As I reached the Sierra Vista lookout, I was treated to crepuscular rays crossing over Bishop, California, and the Eastern Sierra mountains.  It is beautifully majestic scenery, and a highlight of my summer (so far).” Thank you, Ross!
Streamers of crepuscular rays coming out of heavy clouds over the ocean.
View at EarthSky Community Photos. | Cecille Kennedy captured this view on April 26, 2026, in Oregon. Cecille wrote: “Approaching sunset the sun was behind the clouds but shafts of light known as crepuscular rays, broke through the cloud layers. If you look closer there is a dark cloud triangle in the middle where some rays are also emanating. Sunrays (crepuscular rays) are a form of optical illusion based on perspective. While the sun’s rays are actually parallel, they appear to diverge or fan out from the sun due to linear perspective, similar to how parallel train tracks look like they converge in the distance.” Thank you, Cecille!

Photo gallery of crepuscular rays

All of these photos were contributed by EarthSky friends. Thanks for sharing your awesome photos with us! Would you like to contribute? Submit your image here.

Reddish crepuscular rays over a twilight sky.
View at EarthSky Community Photos. | Peter Lowenstein photographed this on February 25, 2026, in Zimbabwe. Peter wrote: “Following the development of rainbow pilei and cloud shadows above the prominent cumulus formation near Murahwa Mountain, the setting sun, which remained hidden, continued to shine brightly beyond and then produced a beautiful display of orange, red and magenta crepuscular rays adjacent to a broad cloud shadow which had developed above the cumulus remnant near the sunset point.” Thank you, Peter!
Twilight at sunset the crepuscular rays - one going over Venus - with trees and bushes in the foreground.
View at EarthSky Community Photos. | Palo Bardelli captured this image on April 30, 2026, in Italy and wrote: “A beautiful sunset with twilight rays created by low clouds. Venus, very bright, is almost in the center of the image.” Thank you, Palo!
Crepuscular rays coming out of several cloud layers over prairie land.
View at EarthSky Community Photos. | Lorraine Boyd shared this image taken on January 2, 2026, in the UK. Lorraine wrote: “It was a beautiful & dramatic scene taking place in the sky, over the Washington County Grasslands. Known as Crepuscular Rays, the sunlight passes through breaks in the clouds, caused by tiny particles (dust, water droplets, haze) in the air scattering this sun light.” Thank you, Lorraine!
Streamers of crepuscular rays coming out of dark clouds over a few houses and prairie land.
Marcy Curran captured this image of crepuscular rays from Wyoming on August 26, 2026.

Bottom line: Crepuscular rays are shadows in the sky of distant terrain or clouds. They form around twilight when particles in the atmosphere reflect the sun’s light beams toward our eyes. Sometimes you can see anticrepuscular rays on the horizon opposite the sun.

Enjoying EarthSky? Sign up for our free daily newsletter today!

The post Crepuscular rays are sunrays in twilight skies first appeared on EarthSky.



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Crepuscular rays coming off the sun above some trees in the distance.
View at EarthSky Community Photos. | Sudhir Sharma photographed this on October 7, 2025, in India, and wrote: “While driving this afternoon we saw this amazing sunset with crepuscular rays.” Thank you, Sudhir!

What are crepuscular rays?

Crepuscular means resembling twilight or dim. This phenomenon occurs around sunrise or sunset, when the sun is below the horizon. And you can also see crepuscular rays when the sun is hiding behind clouds. They’re more noticeable when the sky is a bit darker and there is greater contrast between dark and light. We can see the rays of light thanks to dust, smoke or water droplets that scatter the light toward our eyes.

The darker streaks beside the sunrays are due to shadows, where the terrain or clouds block the sunlight from coming through. Sometimes those obstructions are below the horizon from your point of view, so it may not seem immediately clear what’s causing the darker rays.

When crepuscular rays extend from behind a cloud toward the ground, they also go by the nickname Jacob’s Ladder. The term comes from a story in the Bible where Jacob has a dream in which he sees a ladder leading up to the golden light of heaven with angels ascending and descending.

Parallel lines that seem to converge

Crepuscular rays appear to fan across the sky. But these sunrays are really parallel to each other. In fact, sometimes you can trace them all the way across the sky to the point on the horizon opposite the sunset. So, the next time you see them, remember to turn around. You might spot the fainter and less noticeable anticrepuscular rays. The illusion is similar to standing on train tracks and seeing how they appear to converge in the far distance in front of and behind you.

Black and white image showing crepuscular rays over the Sierra mountains.
View at EarthSky Community Photos. | Ross Stone captured this image on July 15, 2026, from California and wrote: “With the summer heat of the Owens valley being unbearable, an afternoon trip into the White mountains is a must to escape the heat. As I reached the Sierra Vista lookout, I was treated to crepuscular rays crossing over Bishop, California, and the Eastern Sierra mountains.  It is beautifully majestic scenery, and a highlight of my summer (so far).” Thank you, Ross!
Streamers of crepuscular rays coming out of heavy clouds over the ocean.
View at EarthSky Community Photos. | Cecille Kennedy captured this view on April 26, 2026, in Oregon. Cecille wrote: “Approaching sunset the sun was behind the clouds but shafts of light known as crepuscular rays, broke through the cloud layers. If you look closer there is a dark cloud triangle in the middle where some rays are also emanating. Sunrays (crepuscular rays) are a form of optical illusion based on perspective. While the sun’s rays are actually parallel, they appear to diverge or fan out from the sun due to linear perspective, similar to how parallel train tracks look like they converge in the distance.” Thank you, Cecille!

Photo gallery of crepuscular rays

All of these photos were contributed by EarthSky friends. Thanks for sharing your awesome photos with us! Would you like to contribute? Submit your image here.

Reddish crepuscular rays over a twilight sky.
View at EarthSky Community Photos. | Peter Lowenstein photographed this on February 25, 2026, in Zimbabwe. Peter wrote: “Following the development of rainbow pilei and cloud shadows above the prominent cumulus formation near Murahwa Mountain, the setting sun, which remained hidden, continued to shine brightly beyond and then produced a beautiful display of orange, red and magenta crepuscular rays adjacent to a broad cloud shadow which had developed above the cumulus remnant near the sunset point.” Thank you, Peter!
Twilight at sunset the crepuscular rays - one going over Venus - with trees and bushes in the foreground.
View at EarthSky Community Photos. | Palo Bardelli captured this image on April 30, 2026, in Italy and wrote: “A beautiful sunset with twilight rays created by low clouds. Venus, very bright, is almost in the center of the image.” Thank you, Palo!
Crepuscular rays coming out of several cloud layers over prairie land.
View at EarthSky Community Photos. | Lorraine Boyd shared this image taken on January 2, 2026, in the UK. Lorraine wrote: “It was a beautiful & dramatic scene taking place in the sky, over the Washington County Grasslands. Known as Crepuscular Rays, the sunlight passes through breaks in the clouds, caused by tiny particles (dust, water droplets, haze) in the air scattering this sun light.” Thank you, Lorraine!
Streamers of crepuscular rays coming out of dark clouds over a few houses and prairie land.
Marcy Curran captured this image of crepuscular rays from Wyoming on August 26, 2026.

Bottom line: Crepuscular rays are shadows in the sky of distant terrain or clouds. They form around twilight when particles in the atmosphere reflect the sun’s light beams toward our eyes. Sometimes you can see anticrepuscular rays on the horizon opposite the sun.

Enjoying EarthSky? Sign up for our free daily newsletter today!

The post Crepuscular rays are sunrays in twilight skies first appeared on EarthSky.



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Does this Mars image show an alien in a hallway?

Mars image: Rocky ground with some sharp-edged rocks at upper right and what looks like a creature with a round head and rounded body.
View larger. | What do you see in this image from the Mars Curiosity rover, taken on February 24, 2026? Look closely at the upper left portion of the Mars image with the sharp-edged rocks. Does it look like a cute alien walking down a hallway? It’s a classic case of what scientists call pareidolia: the psychological tendency of the human brain to perceive familiar, meaningful patterns — often a human face or body — where none exists. Image via NASA/ JPL-Caltech/ MSSS.

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

Does this Mars image show an alien in a hallway?

On February 24, 2026, the Curiosity rover took the above image on Mars with its Mast Camera. And just recently the image has been making the rounds on social media, with some claiming there’s something unusual in the image. At the upper left, there are some rocks with sharp edges. And if you look closely, you might see what looks like a wee Martian wandering down a hallway! Scientists call seeing things — like faces in rocks — pareidolia.

This is a phenomenon that happens a lot with images of Mars. Mars is a dry, rocky world. And when we see pictures of its surface, our brain is always trying to make sense of them in context of what we already know. So sometimes we see a face on Mars, for example. Or, perhaps, a gorilla mask discarded on the ground. And there was this fun sighting of a doorway on Mars.

But, in reality, these are normally occurring formations on the surface of Mars, formed by natural processes such as wind and water.

What do you think you see in the image at top? Share your thoughts with us in the comments below.

Sandy landscape with rock at left and rectangular-looking doorway at right in steep rocky bank.
The Mars Curiosity rover took this image of Mars on May 7, 2022. Social media came up with theories about this “doorway” on Mars. What do you see? Image via NASA/ JPL-Caltech/ MSSS.

Bottom line: What do you see in the Mars image? Some people think the rocks look like a hallway where a little alien is walking. When our brains see faces and figures that aren’t there, it’s called pareidolia.

The post Does this Mars image show an alien in a hallway? first appeared on EarthSky.



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Mars image: Rocky ground with some sharp-edged rocks at upper right and what looks like a creature with a round head and rounded body.
View larger. | What do you see in this image from the Mars Curiosity rover, taken on February 24, 2026? Look closely at the upper left portion of the Mars image with the sharp-edged rocks. Does it look like a cute alien walking down a hallway? It’s a classic case of what scientists call pareidolia: the psychological tendency of the human brain to perceive familiar, meaningful patterns — often a human face or body — where none exists. Image via NASA/ JPL-Caltech/ MSSS.

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

Does this Mars image show an alien in a hallway?

On February 24, 2026, the Curiosity rover took the above image on Mars with its Mast Camera. And just recently the image has been making the rounds on social media, with some claiming there’s something unusual in the image. At the upper left, there are some rocks with sharp edges. And if you look closely, you might see what looks like a wee Martian wandering down a hallway! Scientists call seeing things — like faces in rocks — pareidolia.

This is a phenomenon that happens a lot with images of Mars. Mars is a dry, rocky world. And when we see pictures of its surface, our brain is always trying to make sense of them in context of what we already know. So sometimes we see a face on Mars, for example. Or, perhaps, a gorilla mask discarded on the ground. And there was this fun sighting of a doorway on Mars.

But, in reality, these are normally occurring formations on the surface of Mars, formed by natural processes such as wind and water.

What do you think you see in the image at top? Share your thoughts with us in the comments below.

Sandy landscape with rock at left and rectangular-looking doorway at right in steep rocky bank.
The Mars Curiosity rover took this image of Mars on May 7, 2022. Social media came up with theories about this “doorway” on Mars. What do you see? Image via NASA/ JPL-Caltech/ MSSS.

Bottom line: What do you see in the Mars image? Some people think the rocks look like a hallway where a little alien is walking. When our brains see faces and figures that aren’t there, it’s called pareidolia.

The post Does this Mars image show an alien in a hallway? first appeared on EarthSky.



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Atlantic hurricane season sets a record: No hurricanes yet!

Map of the Atlantic with the words "Tropical cyclone activity is not expected during the next 7 days."
The Atlantic hurricane season has set a record. It’s now been the longest season on record without a hurricane since the modern era of observing the weather with satellites began in 1966. And there are no storms that are emerging in the immediate future, based on current data. Image via NHC/ NOAA.

We’ve never needed good science more than we do right now. Support EarthSky in 2026 and help us keep it going strong.

Record quiet Atlantic hurricane season so far

As of the morning of September 11, 2026, the Atlantic hurricane season set a new record for the quietest in the modern era. As the National Hurricane Center said on social media:

We officially passed the satellite-era (1966-present) record for the latest formation of the first hurricane during an Atlantic hurricane season, held by Hurricanes Gustav (2002) and Humberto (2013).

It’s important to remember that about half of a normal season’s activity happens after today. In fact, there has never been a season during the satellite era without the formation of at least 2 hurricanes. Late-starting years can still produce hurricane impacts—so stay prepared! Continue to visit Hurricanes.gov for the latest forecast.

Hurricanes Gustav (2002) and Humberto (2013) both formed on September 11 of their respective years.

The forecast for the next seven days will continue the quiet streak we’ve seen so far. While we haven’t had any hurricanes in the Atlantic yet, we have had five named tropical storms: Arthur, Bertha, Cristobal, Dolly and Edouard.

Why the extra-quiet season? El Niño appears to be the driving force.

Why does El Niño mean fewer hurricanes?

El Niño conditions happen when warmer-than-average water pools in the eastern Pacific near equatorial South America. Normally, cold, nutrient-rich water rises from the deep ocean in this area. But El Niño blocks the upwelling of this cold water. So it disrupts marine life and local fisheries. And its effects cascade into Earth’s atmosphere, creating conditions like rainfall and temperature shifts in some parts of the world … and affecting wind shear.

It’s El Niño’s wind shear effects that have a major impact on hurricanes. Wind shear is the change in speed and direction of the wind. Specifically for hurricanes, what matters is the condition of wind shear at 5,000 to 35,000 feet (1,500 m to 10,700 m) above the ground.

In the Atlantic, El Niño can create strong wind shear, so strong it can rip apart storms or prevent them from forming in the first place. El Niño often brings a downstream trough of flowing winds over the Caribbean Sea and western tropical Atlantic. It’s this trough that brings the wind shear that can disrupt hurricane formation or growth. Plus, El Niño can bring sinking air to the region, which is a sign of an area of high pressure. And hurricanes are essentially huge, organized low-pressure systems.

While El Niño hinders the formation of strong hurricane activity in the Atlantic Ocean, it helps hurricane formation in the Pacific. El Niño creates a ridge over parts of the Pacific, which favors conditions such as weaker upper-level winds and less vertical wind shear.

In conditions such as these, hurricanes can grow without obstruction.

Read more: Hurricane triplets spin across the Pacific Ocean

Map of Western Hemisphere showing warm water in the Pacific and notes on hurricanes in Pacific and Atlantic.
View larger. | This map shows the typical influence of El Niño on Pacific and Atlantic seasonal hurricane activity. Image via NOAA/ Climate.gov.

An update to the Atlantic hurricane season forecast

After El Niño conditions were set in place this season, Colorado State University (CSU) revised its earlier hurricane forecast downward. The earlier forecast was already low, but now it is lower still.

On July 8, 2026, CSU predicts just nine named storms and just one major hurricane.

Back on April 9, the CSU forecast had called for 13 named storms, and two major hurricanes.

Both the National Oceanic and Atmospheric Administration (NOAA) and CSU release a forecast for the Atlantic hurricane season yearly. Earlier this year, both organizations called for a below-average year for tropical storms in the Atlantic basin.

CSU said:

Coastal residents are reminded that it only takes one hurricane making landfall to make it an active season for them.

As always, be aware and be prepared.

The original Atlantic hurricane season forecast for 2026

Originally, NOAA released its official forecast for the 2026 Atlantic hurricane season on May 21, 2026. And it predicted a below-average hurricane season, specifically, 8-14 total named storms (this includes both tropical storms and hurricanes), 3-6 hurricanes and 1-3 major hurricanes. NOAA did not make any changes to its 2026 forecast.

Hurricane season runs from June 1 through November 30.

What are the categories of hurricanes? Well, major hurricanes are those that reach Categories 3, 4 or 5.

  • Category 3: 111–129 mph sustained winds (180-209 km/h)
  • Category 4: 130–156 mph sustained winds (210-250 km/h)
  • Category 5: 157 mph or higher sustained winds (251+ km/h)
Atlantic hurricane season: View looking down into tight spiral clouds around a clear center with water visible in it.
The eye of Hurricane Melissa – strongest Atlantic hurricane of 2025 – on October 28, 2025. The Copernicus Sentinel-2 satellite captured this image while looking down from space – from 500 miles (800 km) high – shortly before Melissa hit the Caribbean island of Jamaica. On July 8, 2026, Colorado State University revised its forecast for the Atlantic hurricane season. It said that a strengthening El Niño means even lower chances of tropical storms than its already low forecast from earlier this year. Image via EU/ ESA/ Copernicus Sentinel-2.

Keep up-to-date with tropical conditions

To stay up-to-date on the tropics, visit NOAA’s National Hurricane Center page. You can toggle between Atlantic, Pacific and Central Pacific, as well as 2-day and 7-day forecasts.

Bottom line: The 2026 Atlantic hurricane season has set a record. It’s the longest we’ve ever gone in a hurricane season without seeing a hurricane.

Read more: Here’s the hurricane name list for 2026

The post Atlantic hurricane season sets a record: No hurricanes yet! first appeared on EarthSky.



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Map of the Atlantic with the words "Tropical cyclone activity is not expected during the next 7 days."
The Atlantic hurricane season has set a record. It’s now been the longest season on record without a hurricane since the modern era of observing the weather with satellites began in 1966. And there are no storms that are emerging in the immediate future, based on current data. Image via NHC/ NOAA.

We’ve never needed good science more than we do right now. Support EarthSky in 2026 and help us keep it going strong.

Record quiet Atlantic hurricane season so far

As of the morning of September 11, 2026, the Atlantic hurricane season set a new record for the quietest in the modern era. As the National Hurricane Center said on social media:

We officially passed the satellite-era (1966-present) record for the latest formation of the first hurricane during an Atlantic hurricane season, held by Hurricanes Gustav (2002) and Humberto (2013).

It’s important to remember that about half of a normal season’s activity happens after today. In fact, there has never been a season during the satellite era without the formation of at least 2 hurricanes. Late-starting years can still produce hurricane impacts—so stay prepared! Continue to visit Hurricanes.gov for the latest forecast.

Hurricanes Gustav (2002) and Humberto (2013) both formed on September 11 of their respective years.

The forecast for the next seven days will continue the quiet streak we’ve seen so far. While we haven’t had any hurricanes in the Atlantic yet, we have had five named tropical storms: Arthur, Bertha, Cristobal, Dolly and Edouard.

Why the extra-quiet season? El Niño appears to be the driving force.

Why does El Niño mean fewer hurricanes?

El Niño conditions happen when warmer-than-average water pools in the eastern Pacific near equatorial South America. Normally, cold, nutrient-rich water rises from the deep ocean in this area. But El Niño blocks the upwelling of this cold water. So it disrupts marine life and local fisheries. And its effects cascade into Earth’s atmosphere, creating conditions like rainfall and temperature shifts in some parts of the world … and affecting wind shear.

It’s El Niño’s wind shear effects that have a major impact on hurricanes. Wind shear is the change in speed and direction of the wind. Specifically for hurricanes, what matters is the condition of wind shear at 5,000 to 35,000 feet (1,500 m to 10,700 m) above the ground.

In the Atlantic, El Niño can create strong wind shear, so strong it can rip apart storms or prevent them from forming in the first place. El Niño often brings a downstream trough of flowing winds over the Caribbean Sea and western tropical Atlantic. It’s this trough that brings the wind shear that can disrupt hurricane formation or growth. Plus, El Niño can bring sinking air to the region, which is a sign of an area of high pressure. And hurricanes are essentially huge, organized low-pressure systems.

While El Niño hinders the formation of strong hurricane activity in the Atlantic Ocean, it helps hurricane formation in the Pacific. El Niño creates a ridge over parts of the Pacific, which favors conditions such as weaker upper-level winds and less vertical wind shear.

In conditions such as these, hurricanes can grow without obstruction.

Read more: Hurricane triplets spin across the Pacific Ocean

Map of Western Hemisphere showing warm water in the Pacific and notes on hurricanes in Pacific and Atlantic.
View larger. | This map shows the typical influence of El Niño on Pacific and Atlantic seasonal hurricane activity. Image via NOAA/ Climate.gov.

An update to the Atlantic hurricane season forecast

After El Niño conditions were set in place this season, Colorado State University (CSU) revised its earlier hurricane forecast downward. The earlier forecast was already low, but now it is lower still.

On July 8, 2026, CSU predicts just nine named storms and just one major hurricane.

Back on April 9, the CSU forecast had called for 13 named storms, and two major hurricanes.

Both the National Oceanic and Atmospheric Administration (NOAA) and CSU release a forecast for the Atlantic hurricane season yearly. Earlier this year, both organizations called for a below-average year for tropical storms in the Atlantic basin.

CSU said:

Coastal residents are reminded that it only takes one hurricane making landfall to make it an active season for them.

As always, be aware and be prepared.

The original Atlantic hurricane season forecast for 2026

Originally, NOAA released its official forecast for the 2026 Atlantic hurricane season on May 21, 2026. And it predicted a below-average hurricane season, specifically, 8-14 total named storms (this includes both tropical storms and hurricanes), 3-6 hurricanes and 1-3 major hurricanes. NOAA did not make any changes to its 2026 forecast.

Hurricane season runs from June 1 through November 30.

What are the categories of hurricanes? Well, major hurricanes are those that reach Categories 3, 4 or 5.

  • Category 3: 111–129 mph sustained winds (180-209 km/h)
  • Category 4: 130–156 mph sustained winds (210-250 km/h)
  • Category 5: 157 mph or higher sustained winds (251+ km/h)
Atlantic hurricane season: View looking down into tight spiral clouds around a clear center with water visible in it.
The eye of Hurricane Melissa – strongest Atlantic hurricane of 2025 – on October 28, 2025. The Copernicus Sentinel-2 satellite captured this image while looking down from space – from 500 miles (800 km) high – shortly before Melissa hit the Caribbean island of Jamaica. On July 8, 2026, Colorado State University revised its forecast for the Atlantic hurricane season. It said that a strengthening El Niño means even lower chances of tropical storms than its already low forecast from earlier this year. Image via EU/ ESA/ Copernicus Sentinel-2.

Keep up-to-date with tropical conditions

To stay up-to-date on the tropics, visit NOAA’s National Hurricane Center page. You can toggle between Atlantic, Pacific and Central Pacific, as well as 2-day and 7-day forecasts.

Bottom line: The 2026 Atlantic hurricane season has set a record. It’s the longest we’ve ever gone in a hurricane season without seeing a hurricane.

Read more: Here’s the hurricane name list for 2026

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Anak Krakatau erupts in Indonesia, 8 people missing

Anak Krakatau: Satellite view of a volcano spewing a stream of white ash drifting to the left.
The volcano Anak Krakatau – or Child of Krakatoa – underwent an eruption in Indonesia from September 4 to 6, 2026. Eight people are missing as a result of the eruption. The OLI (Operational Land Imager) on the Landsat 8 satellite acquired this image on September 5, 2026. Image via NASA’s Earth Observatory/ Michala Garrison.

Anak Krakatau erupts in Indonesia

In 1883, Krakatoa volcano in Indonesia erupted so powerfully that it destroyed the majority of its island, triggering 120-foot tsunami waves and producing the loudest sound in recorded history. In 1927, Anak Krakatau – or Child of Krakatoa, emerged from the old caldera. Anak Krakatau erupts fairly regularly. And on September 4, 2026, it roared back to activity, belching gas and ash into the atmosphere. The eruption snarled air traffic in the area. And, while the island itself is no longer inhabited, a boat of eight people, five of them journalists, were headed toward Anak Krakatau to cover the story. After reaching the vicinity of the island, the boat went missing.

In the photo above, the Landsat 8 satellite captured the erupting volcano on September 5. By the next day, the smoke plume had reached 20,000 feet (6,000 m) high to the east and 50,000 feet (15,000 m) to the west.

In a video from September 5, another boat – a fishing boat – captured scenes of the eruption as debris pelted the water all around them.

Mount Anak Krakatau in Indonesia is on its second straight day of a major eruption. Volcanic ash has caused the suspension of flights out of Jakarta's main airport.

— CNN (@cnn.com) 2026-09-07T02:30:17.629752787Z

Are there dangers with Anak Krakatau?

For now, the eruptive period has ended and air travel has resumed. Anak Krakatau regularly erupts, usually in a more mild manner, but these larger outbursts are also not unusual. In 2018, Anak Krakatau erupted and caused part of its island to collapse. That collapse triggered a tsunami that killed 437 in Java and Sumatra.

What can we expect next? Erik Klemetti of Denison University wrote on his Eruptions blog:

What to expect: Likely smaller explosions than the eruption that occurred on September 6 but continued blasts will almost certainly happen. The PVMBG [Indonesia’s Center for Volcanology and Geological Hazard Mitigation] will be watching to see what the seismic activity at the volcano looks like to suggest whether more magma is rising up into the upper parts of the volcanic system. The seismic data for the past few months shows the sharp increase in earthquakes and tremor starting in late August before these new eruptions began.

And while PVMBG did report six volcanoes erupting simultaneously in Indonesia on August 31, this is not unusual behavior for a country on the Ring of Fire.

Satellite view of part of Indonesia showing a long stream of white smoke billowing to the left.
This satellite view by the VIIRS (Visible Infrared Imaging Radiometer Suite) on the Suomi NPP satellite showed smoked billowing away from Anak Krakatau on September 5, 2026. Image via NASA Earth Observatory/ Michala Garrison.

Bottom line: Anak Krakatau erupted in early September, sending a long plume of gas and ash into the atmosphere. Eight people, including 5 journalists who headed toward the eruption by boat, are now missing.

Via NASA

Via Eruptions

The post Anak Krakatau erupts in Indonesia, 8 people missing first appeared on EarthSky.



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Anak Krakatau: Satellite view of a volcano spewing a stream of white ash drifting to the left.
The volcano Anak Krakatau – or Child of Krakatoa – underwent an eruption in Indonesia from September 4 to 6, 2026. Eight people are missing as a result of the eruption. The OLI (Operational Land Imager) on the Landsat 8 satellite acquired this image on September 5, 2026. Image via NASA’s Earth Observatory/ Michala Garrison.

Anak Krakatau erupts in Indonesia

In 1883, Krakatoa volcano in Indonesia erupted so powerfully that it destroyed the majority of its island, triggering 120-foot tsunami waves and producing the loudest sound in recorded history. In 1927, Anak Krakatau – or Child of Krakatoa, emerged from the old caldera. Anak Krakatau erupts fairly regularly. And on September 4, 2026, it roared back to activity, belching gas and ash into the atmosphere. The eruption snarled air traffic in the area. And, while the island itself is no longer inhabited, a boat of eight people, five of them journalists, were headed toward Anak Krakatau to cover the story. After reaching the vicinity of the island, the boat went missing.

In the photo above, the Landsat 8 satellite captured the erupting volcano on September 5. By the next day, the smoke plume had reached 20,000 feet (6,000 m) high to the east and 50,000 feet (15,000 m) to the west.

In a video from September 5, another boat – a fishing boat – captured scenes of the eruption as debris pelted the water all around them.

Mount Anak Krakatau in Indonesia is on its second straight day of a major eruption. Volcanic ash has caused the suspension of flights out of Jakarta's main airport.

— CNN (@cnn.com) 2026-09-07T02:30:17.629752787Z

Are there dangers with Anak Krakatau?

For now, the eruptive period has ended and air travel has resumed. Anak Krakatau regularly erupts, usually in a more mild manner, but these larger outbursts are also not unusual. In 2018, Anak Krakatau erupted and caused part of its island to collapse. That collapse triggered a tsunami that killed 437 in Java and Sumatra.

What can we expect next? Erik Klemetti of Denison University wrote on his Eruptions blog:

What to expect: Likely smaller explosions than the eruption that occurred on September 6 but continued blasts will almost certainly happen. The PVMBG [Indonesia’s Center for Volcanology and Geological Hazard Mitigation] will be watching to see what the seismic activity at the volcano looks like to suggest whether more magma is rising up into the upper parts of the volcanic system. The seismic data for the past few months shows the sharp increase in earthquakes and tremor starting in late August before these new eruptions began.

And while PVMBG did report six volcanoes erupting simultaneously in Indonesia on August 31, this is not unusual behavior for a country on the Ring of Fire.

Satellite view of part of Indonesia showing a long stream of white smoke billowing to the left.
This satellite view by the VIIRS (Visible Infrared Imaging Radiometer Suite) on the Suomi NPP satellite showed smoked billowing away from Anak Krakatau on September 5, 2026. Image via NASA Earth Observatory/ Michala Garrison.

Bottom line: Anak Krakatau erupted in early September, sending a long plume of gas and ash into the atmosphere. Eight people, including 5 journalists who headed toward the eruption by boat, are now missing.

Via NASA

Via Eruptions

The post Anak Krakatau erupts in Indonesia, 8 people missing first appeared on EarthSky.



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What is retrograde motion? And why is the moon moving backwards?

A black circle in the middle of the image hides the sun. The moon enters from the right, makes a turn, then exits toward the right.
This video from the CCOR-1 coronagraph aboard GOES-19 – acquired on September 10, 2026 – blocks the sun’s bright face. So we can watch the faint outer corona, and the space near the sun. You can see a far-side eruption, blasting outward from behind the occulting disk. Also, the moon drifts into the field of view from the right, then slips back out the same way. Did the moon make a turn in orbit? No. Astronomers would say that the moon in this image is exhibiting retrograde motion. The apparent turn is a perspective effect … an illusion. It happens because moon orbits Earth only once each month. The spacecraft moves much faster, completing an orbit around Earth in just one day. So, from the spacecraft’s perspective, it’s as if the moon is a moving car on the highway, with a faster car (our spacecraft) passing it. From the spacecraft’s perspective, for a time, the slower moon appears to move backwards. Image via NOAA.

The retrograde or “backward” motion of a planet is an illusion, a trick of perspective.

Most retrograde motion is an illusion

As measured against the fixed stars, planets typically appear to move eastward throughout the year. But, sometimes, they seem to pause briefly in this eastward motion. They reach what astronomers call a stationary point. Then, for some months, the planet moves westward (backward) in front of the stars. For example, Mars will reach its next stationary point on January 10, 2027. Astronomers (and astrologers) call a planet’s westward motion its retrograde motion.

Though it baffled ancient stargazers, we know now that this type of retrograde motion is an illusion.

You can experience this illusion in an earthbound way, the next time you pass a car on the highway. As you approach a slower car, it’s clearly moving in the same direction you are. But, as you pull alongside and pass it – from your vantage point in the faster car – the slower car may appear to move backwards for a moment. Then, as you pull ahead of it, the car appears to resume its forward motion.

The same thing happens whenever Earth prepares to pass a slower-moving planet whose orbit is bigger than ours. Earth is due to pass between Mars and the sun on February 19, 2027. When we go between the sun and Mars (or another outer planet), these planets – all of which move more slowly than Earth in orbit – appear to reverse course in our sky.

Read more: Why is Mars sometimes bright and sometimes faint?

On a star chart, animated yellow dot moves from right to left, making a big loop in the middle.
An animation showing the retrograde motion of Mars in the summer of 2003. Planets typically move toward the east in front of the stars. When they move west, they’re said to be undergoing retrograde motion. The illusion is caused by our perspective, as seen from Earth. Image via Wikimedia Commons (CC BY-SA 4.0).
Diagram with orbits of inner and outer planets and lines of sight between them at different positions.
A schematic of how retrograde motion works when Earth (T) passes an outer planet (P) as they both orbit the sun (S). The changing viewing angle from Earth makes the projection of the planet against the celestial sphere (A) move backwards (A2-A4) as we pass the slower, outer planet. Image via Wikimedia Commons (CC BY-SA 3.0).

Retrograde motion in inner planets

The above description helps you understand why we see retrograde motion in outer planets. But we can see it in inner planets, too! It just works a bit differently.

We always see the inner planets relatively close to the sun. They can never be opposite the sun in our sky because they are on an orbit inside ours. So we see them before sunrise or after sunset. Venus and Mercury also move east to west daily in our skies (because Earth spins west to east). But because these inner planets are speedier than Earth, we can see them – over the course of days or weeks – rise away from the morning sun. Then as they turn the corner to go behind the sun, from our perspective it looks like they’re falling back toward the sun. At these times, their motion slows as they reach their apex, and then the motion reverses.

In fact, Mercury is the planet that experiences retrograde most often. An Earth-year is 365 days, but Mercury circles the sun in just 88 days. So a few times a year, Mercury is moving away from the sun in the morning or evening sky and then falling back toward it.

It baffled early astronomers

Early astronomers believed Earth lay at the center of the universe. And so they went to complicated lengths to attempt to explain retrograde motion in that Earth-centered universe. They theorized each planet not only orbited Earth, but also spun around a moving point on their orbit known as an epicycle.

Imagine whipping a ball on a length of string around your hand while you turned in place. That’s similar to the ancient view of retrograde motion.

When it became generally accepted that Earth and the other planets orbited the sun, suddenly retrograde motion made a lot more sense.

Diagram: Large circular orbits around Earth, with a smaller circle within one of the large orbits.
A schematic of how astronomers envisioned the motion of the planets before Copernicus. The Earth sat near the center of the universe. The planets moved around a small circle (the epicycle) which in turn moved along a larger circle (the deferent). The deferent was centered on a point (X) midway between the Earth and another spot called the equant. Image via Wikimedia Commons.

Retrograde motion on other worlds

If you could see the sky from another planet besides Earth, retrograde illusions would lead to your seeing some very strange phenomena. On Mercury, for example, the sun sometimes appears to move in retrograde. As Mercury speeds through its closest approach to the sun, its orbital speed overtakes its rotational speed. An astronaut on the surface would see the sun partially rise, then dip back below the horizon, then rise again before resuming its east-to-west trek across the sky. The result is that, once a year, Mercury gets two sunrises on the same day!

Other retrograde motion is real

Astronomers also use the word retrograde to describe true backward motion among planets and moons.

Venus, for example, rotates or spins on its axis in the opposite direction from every other planet in the solar system. If the clouds ever parted, hypothetical Venusians would see the sun rise in the west and set in the east. Astronomers would say that Venus rotates in a retrograde manner.

Some moons also have retrograde orbits around their planets. In other words, most of the large moons orbit in the same direction that their planet spins … but not Triton, for example, the largest moon of Neptune. It orbits opposite the direction of Neptune’s spin.

Among the smaller asteroid-like moons that swarm about the giant planets, many have retrograde orbits.

It’s the same word: retrograde. But now there’s no illusion. Whether speaking of a planet’s rotation – or its orbit – if it’s opposite what you’d expect, astronomers call it retrograde.

Light-colored, blotchy planet-like body half in shadow.
A photomosaic from Voyager 2 of Neptune’s largest moon, Triton. The moon orbits Neptune opposite the direction that the planet rotates. Does this mean that Triton came from the Kuiper Belt and was eventually captured by the ice giant? Image via NASA.

How does it happen?

According to modern astronomers, a true retrograde orbit for an orbiting moon most likely stems from a capture. Triton, for example, might have come out of the Kuiper Belt, the region of icy debris beyond Neptune. Perhaps a collision in the belt sent Triton careening inward toward the sun. A close encounter with Neptune could have slowed it down, forcing it to settle into a backward orbit.

In past decades, astronomers have also discovered planets in distant solar systems with retrograde orbits. These exoplanets orbit their suns in the opposite direction from how the star rotates.

It’s puzzling, because planets form out of debris disks that orbit young stars. And those orbiting disks share the star’s rotation. So how does a planet end up with a true backward orbit? The only way – some astronomers believe – is either by a near-collision with another planet, or if another star once passed too close to the system.

Either way, close encounters can disrupt the orbits of planets and set them on a backward path!

Bottom line: What is retrograde motion? See an image that appears to show the moon moving backwards! An explanation, and more bizarre examples, here.

Read more: Why is Mars sometimes bright and sometimes faint?

The post What is retrograde motion? And why is the moon moving backwards? first appeared on EarthSky.



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A black circle in the middle of the image hides the sun. The moon enters from the right, makes a turn, then exits toward the right.
This video from the CCOR-1 coronagraph aboard GOES-19 – acquired on September 10, 2026 – blocks the sun’s bright face. So we can watch the faint outer corona, and the space near the sun. You can see a far-side eruption, blasting outward from behind the occulting disk. Also, the moon drifts into the field of view from the right, then slips back out the same way. Did the moon make a turn in orbit? No. Astronomers would say that the moon in this image is exhibiting retrograde motion. The apparent turn is a perspective effect … an illusion. It happens because moon orbits Earth only once each month. The spacecraft moves much faster, completing an orbit around Earth in just one day. So, from the spacecraft’s perspective, it’s as if the moon is a moving car on the highway, with a faster car (our spacecraft) passing it. From the spacecraft’s perspective, for a time, the slower moon appears to move backwards. Image via NOAA.

The retrograde or “backward” motion of a planet is an illusion, a trick of perspective.

Most retrograde motion is an illusion

As measured against the fixed stars, planets typically appear to move eastward throughout the year. But, sometimes, they seem to pause briefly in this eastward motion. They reach what astronomers call a stationary point. Then, for some months, the planet moves westward (backward) in front of the stars. For example, Mars will reach its next stationary point on January 10, 2027. Astronomers (and astrologers) call a planet’s westward motion its retrograde motion.

Though it baffled ancient stargazers, we know now that this type of retrograde motion is an illusion.

You can experience this illusion in an earthbound way, the next time you pass a car on the highway. As you approach a slower car, it’s clearly moving in the same direction you are. But, as you pull alongside and pass it – from your vantage point in the faster car – the slower car may appear to move backwards for a moment. Then, as you pull ahead of it, the car appears to resume its forward motion.

The same thing happens whenever Earth prepares to pass a slower-moving planet whose orbit is bigger than ours. Earth is due to pass between Mars and the sun on February 19, 2027. When we go between the sun and Mars (or another outer planet), these planets – all of which move more slowly than Earth in orbit – appear to reverse course in our sky.

Read more: Why is Mars sometimes bright and sometimes faint?

On a star chart, animated yellow dot moves from right to left, making a big loop in the middle.
An animation showing the retrograde motion of Mars in the summer of 2003. Planets typically move toward the east in front of the stars. When they move west, they’re said to be undergoing retrograde motion. The illusion is caused by our perspective, as seen from Earth. Image via Wikimedia Commons (CC BY-SA 4.0).
Diagram with orbits of inner and outer planets and lines of sight between them at different positions.
A schematic of how retrograde motion works when Earth (T) passes an outer planet (P) as they both orbit the sun (S). The changing viewing angle from Earth makes the projection of the planet against the celestial sphere (A) move backwards (A2-A4) as we pass the slower, outer planet. Image via Wikimedia Commons (CC BY-SA 3.0).

Retrograde motion in inner planets

The above description helps you understand why we see retrograde motion in outer planets. But we can see it in inner planets, too! It just works a bit differently.

We always see the inner planets relatively close to the sun. They can never be opposite the sun in our sky because they are on an orbit inside ours. So we see them before sunrise or after sunset. Venus and Mercury also move east to west daily in our skies (because Earth spins west to east). But because these inner planets are speedier than Earth, we can see them – over the course of days or weeks – rise away from the morning sun. Then as they turn the corner to go behind the sun, from our perspective it looks like they’re falling back toward the sun. At these times, their motion slows as they reach their apex, and then the motion reverses.

In fact, Mercury is the planet that experiences retrograde most often. An Earth-year is 365 days, but Mercury circles the sun in just 88 days. So a few times a year, Mercury is moving away from the sun in the morning or evening sky and then falling back toward it.

It baffled early astronomers

Early astronomers believed Earth lay at the center of the universe. And so they went to complicated lengths to attempt to explain retrograde motion in that Earth-centered universe. They theorized each planet not only orbited Earth, but also spun around a moving point on their orbit known as an epicycle.

Imagine whipping a ball on a length of string around your hand while you turned in place. That’s similar to the ancient view of retrograde motion.

When it became generally accepted that Earth and the other planets orbited the sun, suddenly retrograde motion made a lot more sense.

Diagram: Large circular orbits around Earth, with a smaller circle within one of the large orbits.
A schematic of how astronomers envisioned the motion of the planets before Copernicus. The Earth sat near the center of the universe. The planets moved around a small circle (the epicycle) which in turn moved along a larger circle (the deferent). The deferent was centered on a point (X) midway between the Earth and another spot called the equant. Image via Wikimedia Commons.

Retrograde motion on other worlds

If you could see the sky from another planet besides Earth, retrograde illusions would lead to your seeing some very strange phenomena. On Mercury, for example, the sun sometimes appears to move in retrograde. As Mercury speeds through its closest approach to the sun, its orbital speed overtakes its rotational speed. An astronaut on the surface would see the sun partially rise, then dip back below the horizon, then rise again before resuming its east-to-west trek across the sky. The result is that, once a year, Mercury gets two sunrises on the same day!

Other retrograde motion is real

Astronomers also use the word retrograde to describe true backward motion among planets and moons.

Venus, for example, rotates or spins on its axis in the opposite direction from every other planet in the solar system. If the clouds ever parted, hypothetical Venusians would see the sun rise in the west and set in the east. Astronomers would say that Venus rotates in a retrograde manner.

Some moons also have retrograde orbits around their planets. In other words, most of the large moons orbit in the same direction that their planet spins … but not Triton, for example, the largest moon of Neptune. It orbits opposite the direction of Neptune’s spin.

Among the smaller asteroid-like moons that swarm about the giant planets, many have retrograde orbits.

It’s the same word: retrograde. But now there’s no illusion. Whether speaking of a planet’s rotation – or its orbit – if it’s opposite what you’d expect, astronomers call it retrograde.

Light-colored, blotchy planet-like body half in shadow.
A photomosaic from Voyager 2 of Neptune’s largest moon, Triton. The moon orbits Neptune opposite the direction that the planet rotates. Does this mean that Triton came from the Kuiper Belt and was eventually captured by the ice giant? Image via NASA.

How does it happen?

According to modern astronomers, a true retrograde orbit for an orbiting moon most likely stems from a capture. Triton, for example, might have come out of the Kuiper Belt, the region of icy debris beyond Neptune. Perhaps a collision in the belt sent Triton careening inward toward the sun. A close encounter with Neptune could have slowed it down, forcing it to settle into a backward orbit.

In past decades, astronomers have also discovered planets in distant solar systems with retrograde orbits. These exoplanets orbit their suns in the opposite direction from how the star rotates.

It’s puzzling, because planets form out of debris disks that orbit young stars. And those orbiting disks share the star’s rotation. So how does a planet end up with a true backward orbit? The only way – some astronomers believe – is either by a near-collision with another planet, or if another star once passed too close to the system.

Either way, close encounters can disrupt the orbits of planets and set them on a backward path!

Bottom line: What is retrograde motion? See an image that appears to show the moon moving backwards! An explanation, and more bizarre examples, here.

Read more: Why is Mars sometimes bright and sometimes faint?

The post What is retrograde motion? And why is the moon moving backwards? first appeared on EarthSky.



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What is an Equal Earth projection map? See comparisons here


This interactive map compares the Mercator projection versus the Equal Earth projection. Use the slide bar to compare the 2 maps. Image via EqualEarthMap.app.

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

The Equal Earth projection map is in the news

The best map of Earth is a globe. Any flat map will distort some areas. For years, criticism has been leveled at the widely used Mercator projection map for its noticeable distortions. And on September 4, 2026, the U.N. General Assembly voted 164 to 1 – with six abstentions – to encourage the use of equal-area maps – such as the Equal Earth projection – in certain situations over the Mercator projection map.

The ruling does not change any borders or ban the use of the Mercator map. It simply recommends using an equal earth map in situations where seeing areas of Earth in true proportion are useful.

The Mercator map’s biggest drawback is that land closest to the equator looks smaller than it should, while land nearer to the poles looks huge. It’s why people have such a distorted view of the size of Greenland, for instance. And an equal-area Earth map is still a two-dimensional map, so it has its own drawbacks. For example, equal-area maps will distort shapes and angles near the poles.

So what exactly is an equal-area map of Earth?


The best representation of Earth is, of course, a globe. But flat images on pages and screens make globes not always the most practical option. Video by McZerrill/ Pixabay.

What is an Equal Earth projection map?

The Equal Earth map is a specific map invented in 2018. Its goal is to keep the relative size of land masses. Mercator maps are useful because they preserve angles that are important in marine navigation. Equal Earth maps are useful for comparing different regions of the world. As NewWorldMap.org explains:

Equal Earth is a modern equal-area projection designed to keep the relative sizes of countries and continents correct without giving the world an unfamiliar, severely stretched outline.

Equal earth projection: Oval shaped world map with all countries labeled.
View larger. | This is an Equal Earth map. Note how land near the equator, such as Africa, looks larger than on a Mercator projection map (below). Then compare the sizes of Greenland. Image via Tom Patterson/ Wikimedia Commons.
Flat map of Earth showing very large areas near the poles and shrunken areas near the equator.
This is a Mercator projection map. Note how areas near the poles seem outsized, while areas near the equator appear small in comparison. Image via Wikimedia Commons.

What will you see differently?

Africa will likely look larger on the Equal Earth map than you are used to seeing on other flat maps. But if you compare the Equal Earth map to the view of Africa on the spinning globe, you will see they are more in harmony. As a specific example, one of the countries on the equator in Africa – Somalia, which curves around the Horn of Africa – is about the size of the U.S. East Coast.

Over in South America, you can see that Brazil also sits on the equator. The Equal Earth map more accurately shows the large size of Brazil. In fact, Brazil is so large that the country’s northernmost point is closer to Canada than it is to Brazil’s southernmost point.

Note the size of Greenland on the Equal Earth map. On Mercator projection maps, Greenland can look as large as Africa.

6 images of Africa with other areas imposed on top, including the US, Russia, China and more.
Africa is much larger than you are used to seeing on a Mercator projection map. Its length is equal to Russia’s width. The U.S. can fit comfortably inside Northern Africa. Image via Statista.

What other differences do you see between the Equal Earth and Mercator projection maps? Share in the comments below.

Bottom line: Everyone is familiar with the Mercator map, a flattened view of Earth. But what is the Equal Earth projection map, and how does it compare?

Read more: Astrophysicists design ‘radically different’ world map

The post What is an Equal Earth projection map? See comparisons here first appeared on EarthSky.



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This interactive map compares the Mercator projection versus the Equal Earth projection. Use the slide bar to compare the 2 maps. Image via EqualEarthMap.app.

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The Equal Earth projection map is in the news

The best map of Earth is a globe. Any flat map will distort some areas. For years, criticism has been leveled at the widely used Mercator projection map for its noticeable distortions. And on September 4, 2026, the U.N. General Assembly voted 164 to 1 – with six abstentions – to encourage the use of equal-area maps – such as the Equal Earth projection – in certain situations over the Mercator projection map.

The ruling does not change any borders or ban the use of the Mercator map. It simply recommends using an equal earth map in situations where seeing areas of Earth in true proportion are useful.

The Mercator map’s biggest drawback is that land closest to the equator looks smaller than it should, while land nearer to the poles looks huge. It’s why people have such a distorted view of the size of Greenland, for instance. And an equal-area Earth map is still a two-dimensional map, so it has its own drawbacks. For example, equal-area maps will distort shapes and angles near the poles.

So what exactly is an equal-area map of Earth?


The best representation of Earth is, of course, a globe. But flat images on pages and screens make globes not always the most practical option. Video by McZerrill/ Pixabay.

What is an Equal Earth projection map?

The Equal Earth map is a specific map invented in 2018. Its goal is to keep the relative size of land masses. Mercator maps are useful because they preserve angles that are important in marine navigation. Equal Earth maps are useful for comparing different regions of the world. As NewWorldMap.org explains:

Equal Earth is a modern equal-area projection designed to keep the relative sizes of countries and continents correct without giving the world an unfamiliar, severely stretched outline.

Equal earth projection: Oval shaped world map with all countries labeled.
View larger. | This is an Equal Earth map. Note how land near the equator, such as Africa, looks larger than on a Mercator projection map (below). Then compare the sizes of Greenland. Image via Tom Patterson/ Wikimedia Commons.
Flat map of Earth showing very large areas near the poles and shrunken areas near the equator.
This is a Mercator projection map. Note how areas near the poles seem outsized, while areas near the equator appear small in comparison. Image via Wikimedia Commons.

What will you see differently?

Africa will likely look larger on the Equal Earth map than you are used to seeing on other flat maps. But if you compare the Equal Earth map to the view of Africa on the spinning globe, you will see they are more in harmony. As a specific example, one of the countries on the equator in Africa – Somalia, which curves around the Horn of Africa – is about the size of the U.S. East Coast.

Over in South America, you can see that Brazil also sits on the equator. The Equal Earth map more accurately shows the large size of Brazil. In fact, Brazil is so large that the country’s northernmost point is closer to Canada than it is to Brazil’s southernmost point.

Note the size of Greenland on the Equal Earth map. On Mercator projection maps, Greenland can look as large as Africa.

6 images of Africa with other areas imposed on top, including the US, Russia, China and more.
Africa is much larger than you are used to seeing on a Mercator projection map. Its length is equal to Russia’s width. The U.S. can fit comfortably inside Northern Africa. Image via Statista.

What other differences do you see between the Equal Earth and Mercator projection maps? Share in the comments below.

Bottom line: Everyone is familiar with the Mercator map, a flattened view of Earth. But what is the Equal Earth projection map, and how does it compare?

Read more: Astrophysicists design ‘radically different’ world map

The post What is an Equal Earth projection map? See comparisons here first appeared on EarthSky.



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