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Swift spacecraft fiery reentry will be in the next 2 days

Artist concept of golden-looking space telescope with solar panels, in space.
NASA’s Neil Gehrels Swift Observatory has been orbiting Earth since 2004. It’s about to return to Earth in a fireball. Image via NASA.

Update: NASA tried to rescue the falling Swift spacecraft by boosting it back into a higher orbit, but that mission failed in August. And now the spacecraft will likely reenter Earth’s atmosphere around Wednesday. The latest estimate of reentry has been moved up a bit because of recent active solar weather, which degrades a spacecraft’s orbit.

Currently, the estimate for the Swift spacecraft reentry is November 4, 2026, at 05:31 UTC ± 12 hours. If you want to see if the fiery reentry might be visible from your location, you can visit the Swift Last Light website.

In the Americas, the current timing would put it in the afternoon/evening of Tuesday, November 3, or overnight on Wednesday, November 4.

Watch more about Swift

Watch EarthSky’s Dave Adalian talk with Brad Cenko, principal investigator of the Neil Gehrels Swift Observatory.

Swift rescue mission is unsuccessful

On August 19, 2026, NASA said:

Due to an ongoing commercial spacecraft attitude control issue, NASA and Katalyst Space announced Wednesday the LINK spacecraft will not capture or boost an agency satellite to a higher altitude to extend its science mission as planned.

Katalyst Space had launched LINK, a spacecraft meant to capture the failing Swift satellite and boost it into a higher orbit. Swift is a space telescope that watches for events such as gamma-ray bursts. But after more than 20 years, the spacecraft’s orbit has been quickly decaying. It needed a boost back in space or it would crash back to Earth. Unfortunately, the rescue mission will not be able to provide that boost after all. So Swift will fall back to Earth sometime in 2026. Experts expect it will burn up entirely when it hits the atmosphere, so it should not be a danger to anyone on the ground.

Why can’t Swift be saved?

Katalyst’s LINK spacecraft has recently experienced attitude control issues. So it will not be able to capture Swift and boost it higher above Earth. Still, while the main purpose of the mission has failed, NASA and Katalyst will continue to conduct rendezvous and proximity operations with Swift to gather information for the future. NASA Administrator Jared Isaacman said:

This is not the outcome we were working toward, but it does not change why this mission was worth attempting. The team moved with extraordinary speed to give Swift a chance to carry out more science while advancing capabilities America will need for satellite servicing in the future. We are going to learn everything we can from LINK’s rendezvous attempt and put those lessons to work on the missions that follow.

Stay tuned as we learn later this year just when and where Swift will reenter Earth’s atmosphere, likely in October.

LINK as the would-be rescuer

The Neil Gehrels Swift Observatory, better known as Swift, has been orbiting Earth since 2004. It has been studying the most powerful explosions in the universe: gamma-ray bursts. Now, Swift’s orbit is rapidly decaying. That means Swift is slowly falling back to Earth.

And now it looks like nothing will stop it. It’s now destined to put on a spectacular, fiery show.

NASA tried to stop Swift’s fall with a 2nd spacecraft. The would-be rescuer was a commercial robotic repair vehicle called LINK, by Katalyst Space. It launched on July 3, 2026.

So LINK was supposed to chase down Swift, grab it, and raise its orbit. But about three weeks into the mission, two of LINK’s three reaction wheels failed, sending LINK into an uncontrolled spin and causing communication to be intermittent.

A view of the rescue attempt

Amateur astronomers in Puerto Rico – with the Sociedad de Astronomía del Caribe – captured video of both LINK and Swift in the same (or a similar) orbit around Earth. The video comes from Añasco, Puerto Rico, at about 8:02–8:03 p.m. AST on August 10, 2026. Watch the video at the top of this post. And keep reading to learn more.

Swift spacecraft: Small spacecraft with wide solar panels and mechanical arms grabbing a bigger spacecraft.
Meet the space-based Swift Observatory. Its orbit is decaying; it is falling back to Earth. NASA planned to save it and boost it to a higher orbit, with a rescue mission called LINK. The intervention failed and Swift will plunge back to Earth by the fall of 2026. Image via NASA.

Seeing Swift and LINK in orbit

Amateur astronomers frequently try to spy faint spacecraft in orbit around Earth, and LINK and Swift are no exceptions. The website Heavens-Above.com is designed specifically to enable observers to become aware of satellite passes from their location.

The Sociedad de Astronomia del Caribe in Añasco, Puerto Rico, caught both Swift and LINK on video on August 2, 2026. That earlier video showed that Link was about 8 minutes behind the Swift spacecraft.

But, between August 9 and 10, the club’s cameras showed LINK as slightly ahead of Swift in orbit. That’s what you’ll see if you watch the video above.

In the Sociedad de Astronomia del Caribe video at the top of this post, the Link rescue spacecraft passes very close to a bright star. The star is Antares, brightest light in the constellation Scorpius the Scorpion. A minute later, the Swift Observatory is seen also passing by this bright star.

The video capture was possible by analyzing the trajectory of both spacecraft using various sources including Heavens-Above.com.

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

Can you see LINK and Swift?

Observers can try to glimpse the decaying Swift Observatory with the eye. It sometimes reaches a visual magnitude around +2.0 to +1.5, making it as bright as a moderately bright star.

It would be especially easy to spot if you were observing far from city lights, once you know where to look.

The Link rescue spacecraft is fainter and more difficult to see. But some experienced observers have reported seeing it with the unaided eye.

How to spot Swift or LINK

To spot the Swift Observatory or the LINK rescue vehicle in orbit using the website Heavens-Above.com, you need custom visibility predictions for your exact location.  

Here’s how to set your observing location:

  • Navigate to the Heavens-Above main site or open the Heavens-Above mobile app.
  • Click on Configuration (or the location selector in the upper-right corner).
  • Input your specific city or exact GPS coordinates so that pass times and trajectory angles calculate accurately for your horizon.

Here’s how to find the 2 spacecraft:

  • Return to the main database menu and locate the Satellites section.
  • Select Search database for satellite (or use the Satellite database / Search link).
  • Query for Swift (the Neil Gehrels Swift Observatory, NORAD ID 28485) or LINK (or Katalyst Space / Pegasus XL payload related to the mission).

Here’s how to generate the pass predictions:

  • Open the satellite’s details page and click 10-day predictions for visible passes (or change filters to show “All passes” if you want daytime/radio passes).  
  • Review the pass table for key metrics. These are: start/ highest/ end times; altitude aka elevation (look for passes exceeding 30 to 40 degrees elevation for clear viewing above trees or buildings); and brightness aka magnitude (lower or negative numbers indicate brighter objects, and Swift typically reaches a visual magnitude of around +1.5 to +2.0, making it visible to the unaided eye under dark sky conditions.)

Here’s how to use the interactive sky charts

  • Click on any specific date/pass row to generate a star chart.
  • The chart overlays the satellite’s precise trajectory against recognizable constellations and stars (such as Scorpius or Antares), showing you exactly where to aim your eyes, binoculars, or camera equipment.

This video walk-through shows how to set up your ground coordinates and fetch pass predictions on Heavens-Above: How to Track the ISS with Heavens-Above.com.

Five people in white suits in a clean room looking at a spacecraft hanging above the floor.
Engineers from Katalyst Space test the LINK spacecraft before it was launched in an attempt to save Swift. Image via Scott Wiessinger/ NASA.

More about the Swift spacecraft

The Swift spacecraft has three telescopes that watch the night sky. They are the Burst Alert Telescope, X-Ray Telescope and Ultraviolet/Optical Telescope.

The Burst Alert Telescope (BAT) is Swift’s wide-field gamma-ray detector. This telescope continuously monitors a large portion of the sky, watching for sudden flashes of high-energy gamma rays from gamma-ray bursts. When it detects a burst, it quickly calculates the object’s position and sends the coordinates to astronomers worldwide. It also directs the Swift spacecraft to rapidly turn toward the event for closer study.

X-Ray Telescope and Ultraviolet/Optical Telescope

Once Swift has slewed toward a newly detected gamma-ray burst, the X-Ray Telescope (XRT) takes over. It observes the burst’s fading X-ray afterglow. And it measures how its brightness changes over time and analyzes the energies of the emitted X-rays. Also, the XRT can pinpoint a burst’s location better than BAT and can continue tracking the event for days or even weeks. So the XRT helps scientists understand the physics of these powerful explosions and their environments.

Finally, the Ultraviolet/Optical Telescope studies gamma-ray bursts and other cosmic objects in ultraviolet and visible light. It provides Swift’s most precise positions for newly discovered bursts. It also captures details about their brightness, color and evolution. Overall, these observations help astronomers determine distances, identify host galaxies and better understand the nature of the explosions and other transient events Swift observes across the universe.

Bottom line: The Swift spacecraft is falling back to Earth. It will likely burn up in our atmosphere on November 3 or 4. Will you see it?

Via NASA

Read more: What is the Earth’s most distant spacecraft?

Read more: Remember when DART struck an asteroid? New surprises!

The post Swift spacecraft fiery reentry will be in the next 2 days first appeared on EarthSky.



from EarthSky https://ift.tt/s9UJ62a
Artist concept of golden-looking space telescope with solar panels, in space.
NASA’s Neil Gehrels Swift Observatory has been orbiting Earth since 2004. It’s about to return to Earth in a fireball. Image via NASA.

Update: NASA tried to rescue the falling Swift spacecraft by boosting it back into a higher orbit, but that mission failed in August. And now the spacecraft will likely reenter Earth’s atmosphere around Wednesday. The latest estimate of reentry has been moved up a bit because of recent active solar weather, which degrades a spacecraft’s orbit.

Currently, the estimate for the Swift spacecraft reentry is November 4, 2026, at 05:31 UTC ± 12 hours. If you want to see if the fiery reentry might be visible from your location, you can visit the Swift Last Light website.

In the Americas, the current timing would put it in the afternoon/evening of Tuesday, November 3, or overnight on Wednesday, November 4.

Watch more about Swift

Watch EarthSky’s Dave Adalian talk with Brad Cenko, principal investigator of the Neil Gehrels Swift Observatory.

Swift rescue mission is unsuccessful

On August 19, 2026, NASA said:

Due to an ongoing commercial spacecraft attitude control issue, NASA and Katalyst Space announced Wednesday the LINK spacecraft will not capture or boost an agency satellite to a higher altitude to extend its science mission as planned.

Katalyst Space had launched LINK, a spacecraft meant to capture the failing Swift satellite and boost it into a higher orbit. Swift is a space telescope that watches for events such as gamma-ray bursts. But after more than 20 years, the spacecraft’s orbit has been quickly decaying. It needed a boost back in space or it would crash back to Earth. Unfortunately, the rescue mission will not be able to provide that boost after all. So Swift will fall back to Earth sometime in 2026. Experts expect it will burn up entirely when it hits the atmosphere, so it should not be a danger to anyone on the ground.

Why can’t Swift be saved?

Katalyst’s LINK spacecraft has recently experienced attitude control issues. So it will not be able to capture Swift and boost it higher above Earth. Still, while the main purpose of the mission has failed, NASA and Katalyst will continue to conduct rendezvous and proximity operations with Swift to gather information for the future. NASA Administrator Jared Isaacman said:

This is not the outcome we were working toward, but it does not change why this mission was worth attempting. The team moved with extraordinary speed to give Swift a chance to carry out more science while advancing capabilities America will need for satellite servicing in the future. We are going to learn everything we can from LINK’s rendezvous attempt and put those lessons to work on the missions that follow.

Stay tuned as we learn later this year just when and where Swift will reenter Earth’s atmosphere, likely in October.

LINK as the would-be rescuer

The Neil Gehrels Swift Observatory, better known as Swift, has been orbiting Earth since 2004. It has been studying the most powerful explosions in the universe: gamma-ray bursts. Now, Swift’s orbit is rapidly decaying. That means Swift is slowly falling back to Earth.

And now it looks like nothing will stop it. It’s now destined to put on a spectacular, fiery show.

NASA tried to stop Swift’s fall with a 2nd spacecraft. The would-be rescuer was a commercial robotic repair vehicle called LINK, by Katalyst Space. It launched on July 3, 2026.

So LINK was supposed to chase down Swift, grab it, and raise its orbit. But about three weeks into the mission, two of LINK’s three reaction wheels failed, sending LINK into an uncontrolled spin and causing communication to be intermittent.

A view of the rescue attempt

Amateur astronomers in Puerto Rico – with the Sociedad de Astronomía del Caribe – captured video of both LINK and Swift in the same (or a similar) orbit around Earth. The video comes from Añasco, Puerto Rico, at about 8:02–8:03 p.m. AST on August 10, 2026. Watch the video at the top of this post. And keep reading to learn more.

Swift spacecraft: Small spacecraft with wide solar panels and mechanical arms grabbing a bigger spacecraft.
Meet the space-based Swift Observatory. Its orbit is decaying; it is falling back to Earth. NASA planned to save it and boost it to a higher orbit, with a rescue mission called LINK. The intervention failed and Swift will plunge back to Earth by the fall of 2026. Image via NASA.

Seeing Swift and LINK in orbit

Amateur astronomers frequently try to spy faint spacecraft in orbit around Earth, and LINK and Swift are no exceptions. The website Heavens-Above.com is designed specifically to enable observers to become aware of satellite passes from their location.

The Sociedad de Astronomia del Caribe in Añasco, Puerto Rico, caught both Swift and LINK on video on August 2, 2026. That earlier video showed that Link was about 8 minutes behind the Swift spacecraft.

But, between August 9 and 10, the club’s cameras showed LINK as slightly ahead of Swift in orbit. That’s what you’ll see if you watch the video above.

In the Sociedad de Astronomia del Caribe video at the top of this post, the Link rescue spacecraft passes very close to a bright star. The star is Antares, brightest light in the constellation Scorpius the Scorpion. A minute later, the Swift Observatory is seen also passing by this bright star.

The video capture was possible by analyzing the trajectory of both spacecraft using various sources including Heavens-Above.com.

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

Can you see LINK and Swift?

Observers can try to glimpse the decaying Swift Observatory with the eye. It sometimes reaches a visual magnitude around +2.0 to +1.5, making it as bright as a moderately bright star.

It would be especially easy to spot if you were observing far from city lights, once you know where to look.

The Link rescue spacecraft is fainter and more difficult to see. But some experienced observers have reported seeing it with the unaided eye.

How to spot Swift or LINK

To spot the Swift Observatory or the LINK rescue vehicle in orbit using the website Heavens-Above.com, you need custom visibility predictions for your exact location.  

Here’s how to set your observing location:

  • Navigate to the Heavens-Above main site or open the Heavens-Above mobile app.
  • Click on Configuration (or the location selector in the upper-right corner).
  • Input your specific city or exact GPS coordinates so that pass times and trajectory angles calculate accurately for your horizon.

Here’s how to find the 2 spacecraft:

  • Return to the main database menu and locate the Satellites section.
  • Select Search database for satellite (or use the Satellite database / Search link).
  • Query for Swift (the Neil Gehrels Swift Observatory, NORAD ID 28485) or LINK (or Katalyst Space / Pegasus XL payload related to the mission).

Here’s how to generate the pass predictions:

  • Open the satellite’s details page and click 10-day predictions for visible passes (or change filters to show “All passes” if you want daytime/radio passes).  
  • Review the pass table for key metrics. These are: start/ highest/ end times; altitude aka elevation (look for passes exceeding 30 to 40 degrees elevation for clear viewing above trees or buildings); and brightness aka magnitude (lower or negative numbers indicate brighter objects, and Swift typically reaches a visual magnitude of around +1.5 to +2.0, making it visible to the unaided eye under dark sky conditions.)

Here’s how to use the interactive sky charts

  • Click on any specific date/pass row to generate a star chart.
  • The chart overlays the satellite’s precise trajectory against recognizable constellations and stars (such as Scorpius or Antares), showing you exactly where to aim your eyes, binoculars, or camera equipment.

This video walk-through shows how to set up your ground coordinates and fetch pass predictions on Heavens-Above: How to Track the ISS with Heavens-Above.com.

Five people in white suits in a clean room looking at a spacecraft hanging above the floor.
Engineers from Katalyst Space test the LINK spacecraft before it was launched in an attempt to save Swift. Image via Scott Wiessinger/ NASA.

More about the Swift spacecraft

The Swift spacecraft has three telescopes that watch the night sky. They are the Burst Alert Telescope, X-Ray Telescope and Ultraviolet/Optical Telescope.

The Burst Alert Telescope (BAT) is Swift’s wide-field gamma-ray detector. This telescope continuously monitors a large portion of the sky, watching for sudden flashes of high-energy gamma rays from gamma-ray bursts. When it detects a burst, it quickly calculates the object’s position and sends the coordinates to astronomers worldwide. It also directs the Swift spacecraft to rapidly turn toward the event for closer study.

X-Ray Telescope and Ultraviolet/Optical Telescope

Once Swift has slewed toward a newly detected gamma-ray burst, the X-Ray Telescope (XRT) takes over. It observes the burst’s fading X-ray afterglow. And it measures how its brightness changes over time and analyzes the energies of the emitted X-rays. Also, the XRT can pinpoint a burst’s location better than BAT and can continue tracking the event for days or even weeks. So the XRT helps scientists understand the physics of these powerful explosions and their environments.

Finally, the Ultraviolet/Optical Telescope studies gamma-ray bursts and other cosmic objects in ultraviolet and visible light. It provides Swift’s most precise positions for newly discovered bursts. It also captures details about their brightness, color and evolution. Overall, these observations help astronomers determine distances, identify host galaxies and better understand the nature of the explosions and other transient events Swift observes across the universe.

Bottom line: The Swift spacecraft is falling back to Earth. It will likely burn up in our atmosphere on November 3 or 4. Will you see it?

Via NASA

Read more: What is the Earth’s most distant spacecraft?

Read more: Remember when DART struck an asteroid? New surprises!

The post Swift spacecraft fiery reentry will be in the next 2 days first appeared on EarthSky.



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Did the Viking 2 lander detect marsquakes in 1976?

Marsquakes: Partial view of a robotic machine on reddish, rocky terrain, with dusty sky.
NASA’s Viking 2 landed on Mars in 1976. It detected 2 possible marsquakes, on sols 53 and 80. Decades later, NASA’s InSight lander detected nearly 1,000 marsquakes, some of them in the same region as the Viking 2 events. Image via NASA/ JPL-Caltech.
  • Mars has marsquakes, the equivalent of Earth’s earthquakes. They show this neighboring planet is still seismically active.
  • NASA’s Viking 2 lander detected two possible marsquakes back in 1976. But they weren’t confirmed at the time.
  • From 2018 to 2022, NASA’s InSight lander detected nearly 1,000 marsquakes. A new analysis shows that some of them were from the same region as the 1976 Viking 2 detections.

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

Marsquakes in the same place decades apart

The Viking 2 lander — 4th spacecraft from Earth ever to land on Mars — touched down on September 3, 1976. It landed in a region we earthlings call Utopia Planitia. Viking 2’s job was to search for signs of Martian life (it didn’t conclusively find any). It did carry a seismometer, with the hope it might detect marsquakes. But the instrument — mounted on the top deck of the lander — was susceptible to the Martian wind. And it was hard for scientists to separate true seismology from the wind’s vibrational “noise.”

Still, Viking 2 did detect what scientists believed were two small marsquakes on the plains of Utopia Planitia. It felt them on sol 53 and sol 80 of the mission. A sol is a Martian day, slightly longer than an Earth day.

Fast forward some four decades. Now, another Mars spacecraft — NASA’s InSight lander, which set down in Elysium Planitia in 2018 — has detected nearly 1,000 marsquakes in the same approximate region where Viking 2 landed in 1976. Has InSight confirmed Viking 2’s marsquakes? Not exactly. But by comparing the data from the two missions, scientists have gained new clues to the seismic history of Mars.

The researchers published their peer-reviewed findings in AGU Advances on September 30, 2026.

And Matthew R. Francis wrote about the new findings for Eos on October 21, 2026.

Artist's illustration of a robot spacecraft on a red desert plain.
Artist’s concept of NASA’s Mars InSight lander. It touched down on Mars on November 26, 2018. Image via NASA/ JPL/ Caltech.

Comparing the data

Viking 2’s landing site in Utopia Planitia — and InSight’s landing site in Elysium Planitia — are both in Mars’ northern lowlands. They are geographically adjacent regions, so similar that scientists and science journalists often refer to the Elysium-Utopia basin.

In the decades in between Viking 2 and InSight, scientists have pondered whether Mars was still geologically active. Now we know the planet does still experience marsquakes, the Martian equivalent of earthquakes.

Wanbo Xiao at Peking University in China is the lead author of the new InSight study. Xiao and his team compared the data from the old Viking 2 mission to the more recent data from InSight.

While one of the two detections by Viking 2 was dubious (probably because of the wind), the second one appeared more likely to be an actual marsquake.

Of course, though, Viking 2 had just one tiny seismometer, on its deck. And InSight was designed specifically to look for marsquakes or other seismic activity below the Martian surface. Its seismometer was more advanced and placed directly on the ground. The paper states:

For nearly 50 years, scientists debated whether the candidate seismic signals recorded by Viking 2 reflected true Martian tectonics, considering limitations of the Viking instrument. Decades later, the substantial marsquakes detected by the InSight mission revealed a clearer seismic context of the planet. Here we reconstruct the original Viking seismic workflow and reexamine its candidate events, recorded on sol 53 and sol 80, using modern knowledge from InSight.

Robotic lander on a planetary surface, with view of layers of rock beneath it in orange colors.
View larger. | Illustration depicting NASA’s InSight lander, with a cutaway view of the subsurface of Mars. Image via PGP/ Nicolas Sarter/ Jet Propulsion Laboratory/ NASA.

Marsquake or meteorite impact?

Viking 2’s sol 80 event was in the same region in Mars’ northern plains as the InSight detections. But — even after all these decades — it’s still not clear if it was an actual marsquake. It’s possible that a meteorite impact caused the seismic waves. As the paper notes:

The sol 80 event possibly located in the same northern-plains source region inferred for InSight seasonal marsquakes, although a distant tectonic marsquake or a meteorite impact remain as alternative explanations. The faster decay of the sol 80 event than typical InSight marsquakes could imply lateral variations of structural energy absorption in the Martian subsurface.

More broadly, this study shows how a historical planetary data set can gain new scientific implications when revisited using later mission data.

So what is the explanation for the differences between the Viking 2 data and the InSight data? The researchers conclude that there are probably several reasons. As they mentioned in the paper:

Fifty years after Viking 2 returned the first seismic observations from Mars, we reconstruct its unique seismic workflow and reassess the most credible candidate event, the sol 80 signal, using knowledge gained from the InSight mission. Our analysis reveals that the apparent contrast between Viking and InSight seismic observations primarily reflects differences in instrument response, sampling strategy, and the distinct spectral characteristics of Martian seismic events, rather than a change in Martian activity alone.

Marsquakes offer clues to seismic history on Mars

The sol 80 event in particular provides more clues to the history of seismic activity on Mars. As the paper explains:

The Viking 2 sol 80 event provides new constraints on Mars’ seismic history. Its independently inferred location overlaps the broad northern-plains region associated with InSight seasonal marsquakes, suggesting a possible long-lived active region outside Cerberus Fossae. However, alternative origins, including a distant tectonic marsquake analogous to InSight BB [broadband] events or a meteorite impact analogous to VF [very high frequency] events, cannot be excluded.

Small white metallic dome with long tether attached sitting on reddish dusty ground with small rocks and dusty sky.
View larger. | NASA’s InSight lander took this image of its seismometer on sol 96 (March 5, 2019). InSight detected many marsquakes in the subsurface but not aquifers. If they exist, they are probably too deep for detection with a regular radar. Image via NASA/ JPL-Caltech.

Mars’ ‘Grand Canyon’ and others also still active

Valles Marineris. Scientists with Columbia University and Imperial College London just reported this month that the so-called Mars’ Grand Canyon — Valles Marineris — also is still experiencing marsquakes. That data came from the InSight lander, too. Valles Marineris is located south and southwest of both Utopia Planitia and Elysium Planitia. It straddles the Martian equator and stretches more than 2,500 miles (4,000 km), nine times longer than the Grand Canyon on Earth.

Cerberus Fossae. This is Mars’ primary seismic “hotspot.” It’s located east of InSight’s landing site and is a system of massive, young parallel fissures and faults running through the crust. InSight traced hundreds of marsquakes directly to magma movement, localized faulting, and active stress release in this region.

Tharsis Volcanic Region. Other distant, low-frequency quakes were traced back toward the Tharsis rise — the vast volcanic plateau home to Olympus Mons and the three massive Tharsis Montes volcanoes — indicating deep mantle activity or residual cooling under the volcanoes.

In addition, InSight recorded several seismic signals that appeared to be non-tectonic “impact quakes” caused by meteoroid strikes. Mars orbiters confirmed these by spotting fresh, newly formed impact craters in regions like Amazonis Planitia and Cerberus Fossae.

Huge canyon system on a brownish-red planet viewed from space, with a bright sun in the distance.
View larger. | Artist’s concept of the view over Valles Marineris, aka the Grand Canyon of Mars. Researchers have found new evidence for an ancient Mars ocean within the canyon. Still-visible deltas show that rivers once emptied into this alien ocean along an ancient shoreline, including in Coprates Chasma in the southeastern part of the canyon system. Image via Kevin Gill/ Flickr.

Bottom line: New analysis shows that two possible marsquakes detected by Viking 2 were in the same region as nearly 1,000 others detected by the InSight lander decades later.

Source: Fifty Years Later: Revisiting Viking 2 Seismic Signals Through InSight

Via Eos

Read more:

Marsquakes might explain Mars’ north-south hemisphere differences

Marsquakes reveal red planet’s deep secrets

InSight Lander reveals 1st marsquakes on Mars

The post Did the Viking 2 lander detect marsquakes in 1976? first appeared on EarthSky.



from EarthSky https://ift.tt/mEeO9vx
Marsquakes: Partial view of a robotic machine on reddish, rocky terrain, with dusty sky.
NASA’s Viking 2 landed on Mars in 1976. It detected 2 possible marsquakes, on sols 53 and 80. Decades later, NASA’s InSight lander detected nearly 1,000 marsquakes, some of them in the same region as the Viking 2 events. Image via NASA/ JPL-Caltech.
  • Mars has marsquakes, the equivalent of Earth’s earthquakes. They show this neighboring planet is still seismically active.
  • NASA’s Viking 2 lander detected two possible marsquakes back in 1976. But they weren’t confirmed at the time.
  • From 2018 to 2022, NASA’s InSight lander detected nearly 1,000 marsquakes. A new analysis shows that some of them were from the same region as the 1976 Viking 2 detections.

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

Marsquakes in the same place decades apart

The Viking 2 lander — 4th spacecraft from Earth ever to land on Mars — touched down on September 3, 1976. It landed in a region we earthlings call Utopia Planitia. Viking 2’s job was to search for signs of Martian life (it didn’t conclusively find any). It did carry a seismometer, with the hope it might detect marsquakes. But the instrument — mounted on the top deck of the lander — was susceptible to the Martian wind. And it was hard for scientists to separate true seismology from the wind’s vibrational “noise.”

Still, Viking 2 did detect what scientists believed were two small marsquakes on the plains of Utopia Planitia. It felt them on sol 53 and sol 80 of the mission. A sol is a Martian day, slightly longer than an Earth day.

Fast forward some four decades. Now, another Mars spacecraft — NASA’s InSight lander, which set down in Elysium Planitia in 2018 — has detected nearly 1,000 marsquakes in the same approximate region where Viking 2 landed in 1976. Has InSight confirmed Viking 2’s marsquakes? Not exactly. But by comparing the data from the two missions, scientists have gained new clues to the seismic history of Mars.

The researchers published their peer-reviewed findings in AGU Advances on September 30, 2026.

And Matthew R. Francis wrote about the new findings for Eos on October 21, 2026.

Artist's illustration of a robot spacecraft on a red desert plain.
Artist’s concept of NASA’s Mars InSight lander. It touched down on Mars on November 26, 2018. Image via NASA/ JPL/ Caltech.

Comparing the data

Viking 2’s landing site in Utopia Planitia — and InSight’s landing site in Elysium Planitia — are both in Mars’ northern lowlands. They are geographically adjacent regions, so similar that scientists and science journalists often refer to the Elysium-Utopia basin.

In the decades in between Viking 2 and InSight, scientists have pondered whether Mars was still geologically active. Now we know the planet does still experience marsquakes, the Martian equivalent of earthquakes.

Wanbo Xiao at Peking University in China is the lead author of the new InSight study. Xiao and his team compared the data from the old Viking 2 mission to the more recent data from InSight.

While one of the two detections by Viking 2 was dubious (probably because of the wind), the second one appeared more likely to be an actual marsquake.

Of course, though, Viking 2 had just one tiny seismometer, on its deck. And InSight was designed specifically to look for marsquakes or other seismic activity below the Martian surface. Its seismometer was more advanced and placed directly on the ground. The paper states:

For nearly 50 years, scientists debated whether the candidate seismic signals recorded by Viking 2 reflected true Martian tectonics, considering limitations of the Viking instrument. Decades later, the substantial marsquakes detected by the InSight mission revealed a clearer seismic context of the planet. Here we reconstruct the original Viking seismic workflow and reexamine its candidate events, recorded on sol 53 and sol 80, using modern knowledge from InSight.

Robotic lander on a planetary surface, with view of layers of rock beneath it in orange colors.
View larger. | Illustration depicting NASA’s InSight lander, with a cutaway view of the subsurface of Mars. Image via PGP/ Nicolas Sarter/ Jet Propulsion Laboratory/ NASA.

Marsquake or meteorite impact?

Viking 2’s sol 80 event was in the same region in Mars’ northern plains as the InSight detections. But — even after all these decades — it’s still not clear if it was an actual marsquake. It’s possible that a meteorite impact caused the seismic waves. As the paper notes:

The sol 80 event possibly located in the same northern-plains source region inferred for InSight seasonal marsquakes, although a distant tectonic marsquake or a meteorite impact remain as alternative explanations. The faster decay of the sol 80 event than typical InSight marsquakes could imply lateral variations of structural energy absorption in the Martian subsurface.

More broadly, this study shows how a historical planetary data set can gain new scientific implications when revisited using later mission data.

So what is the explanation for the differences between the Viking 2 data and the InSight data? The researchers conclude that there are probably several reasons. As they mentioned in the paper:

Fifty years after Viking 2 returned the first seismic observations from Mars, we reconstruct its unique seismic workflow and reassess the most credible candidate event, the sol 80 signal, using knowledge gained from the InSight mission. Our analysis reveals that the apparent contrast between Viking and InSight seismic observations primarily reflects differences in instrument response, sampling strategy, and the distinct spectral characteristics of Martian seismic events, rather than a change in Martian activity alone.

Marsquakes offer clues to seismic history on Mars

The sol 80 event in particular provides more clues to the history of seismic activity on Mars. As the paper explains:

The Viking 2 sol 80 event provides new constraints on Mars’ seismic history. Its independently inferred location overlaps the broad northern-plains region associated with InSight seasonal marsquakes, suggesting a possible long-lived active region outside Cerberus Fossae. However, alternative origins, including a distant tectonic marsquake analogous to InSight BB [broadband] events or a meteorite impact analogous to VF [very high frequency] events, cannot be excluded.

Small white metallic dome with long tether attached sitting on reddish dusty ground with small rocks and dusty sky.
View larger. | NASA’s InSight lander took this image of its seismometer on sol 96 (March 5, 2019). InSight detected many marsquakes in the subsurface but not aquifers. If they exist, they are probably too deep for detection with a regular radar. Image via NASA/ JPL-Caltech.

Mars’ ‘Grand Canyon’ and others also still active

Valles Marineris. Scientists with Columbia University and Imperial College London just reported this month that the so-called Mars’ Grand Canyon — Valles Marineris — also is still experiencing marsquakes. That data came from the InSight lander, too. Valles Marineris is located south and southwest of both Utopia Planitia and Elysium Planitia. It straddles the Martian equator and stretches more than 2,500 miles (4,000 km), nine times longer than the Grand Canyon on Earth.

Cerberus Fossae. This is Mars’ primary seismic “hotspot.” It’s located east of InSight’s landing site and is a system of massive, young parallel fissures and faults running through the crust. InSight traced hundreds of marsquakes directly to magma movement, localized faulting, and active stress release in this region.

Tharsis Volcanic Region. Other distant, low-frequency quakes were traced back toward the Tharsis rise — the vast volcanic plateau home to Olympus Mons and the three massive Tharsis Montes volcanoes — indicating deep mantle activity or residual cooling under the volcanoes.

In addition, InSight recorded several seismic signals that appeared to be non-tectonic “impact quakes” caused by meteoroid strikes. Mars orbiters confirmed these by spotting fresh, newly formed impact craters in regions like Amazonis Planitia and Cerberus Fossae.

Huge canyon system on a brownish-red planet viewed from space, with a bright sun in the distance.
View larger. | Artist’s concept of the view over Valles Marineris, aka the Grand Canyon of Mars. Researchers have found new evidence for an ancient Mars ocean within the canyon. Still-visible deltas show that rivers once emptied into this alien ocean along an ancient shoreline, including in Coprates Chasma in the southeastern part of the canyon system. Image via Kevin Gill/ Flickr.

Bottom line: New analysis shows that two possible marsquakes detected by Viking 2 were in the same region as nearly 1,000 others detected by the InSight lander decades later.

Source: Fifty Years Later: Revisiting Viking 2 Seismic Signals Through InSight

Via Eos

Read more:

Marsquakes might explain Mars’ north-south hemisphere differences

Marsquakes reveal red planet’s deep secrets

InSight Lander reveals 1st marsquakes on Mars

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November birthstone: Choose from either topaz or citrine

November birthstone: Two golden colored, transparent colored gemstones, one a natural crystal and one faceted.
A natural topaz crystal and a faceted topaz. Topaz is 1 of the 2 options for the November birthstone. The other choice is citrine. Image via Didier Descouens/ Wikipedia.

Topaz, a November birthstone

Topaz, one of two November birthstones, an exquisite gem of many colors, is a much sought-after gemstone for jewelry. In ancient times, people believed that topaz possessed magical and healing qualities. Its name may originate from the Sanskrit word for fire.

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

Colors of topaz

Topaz occurs in a range of magnificent colors: pale blue, pink, red, brown, varying shades of yellow, and even black. However, pure topaz itself is a colorless stone. Some red and some pink topazes get their colors from chromium atoms in the crystal. Most other colors occur due to minor element substitutions and defects in the crystal. However, some colors are unstable and can fade away. Heat can cause color changes. But high-energy irradiation of colorless topaz can transform it to blue gemstones.

Chemically, topaz is an aluminum silicate mineral containing fluorine and hydroxide (a hydrogen-oxygen molecule). Strong chemical bonds within topaz make it the hardest of silicate minerals, rating 8 on the Mohs scale. According to Geoscience Australia, high concentrations of fluorine — a condition needed for topaz formation — are geologically rare. They explained that topaz forms in cavities in certain igneous rocks:

The crystals grow in the late stages of a magma cooling, when there is enough fluorine to enable the formation of topaz. Some topaz crystals grow after hot fluids (hydrothermal solutions), rich in fluorine, flow through cracks in rocks that have already cooled.

Glittering faceted gemstones in several colors: round, oval, square, and triangular.
Different colors of topaz. Image via Michelle Jo/ Wikipedia.

Topaz on display

Topaz gemstones occur in many sizes, from tiny crystals to large rocks. For example, one of the biggest uncut topaz stones, a specimen from Brazil, weighs almost 600 pounds (270 kg). It’s on display at the American Museum of Natural History in New York.

And one of the largest cut topazes in the world – the American Golden Topaz – resides at the Smithsonian Museum of Natural History in Washington, D.C. It weighs 10.1 pounds (4.6 kg) and is about 7 inches (18 cm) in length.

Uses for topaz

The lively fire, clarity, colors and hardness of topaz make it ideal for jewelry such as necklaces, brooches and bracelets. People sometimes mistake colorless pure topaz for a diamond. Because of its rarity, topaz is an expensive gem. The most valued and rarest color is red. Imperial topaz — sherry-colored varieties of brownish-yellow, orange-yellow and reddish brown — are the most popular topaz stones. They command high prices, as do pink stones. Light blue and pale yellow topazes are of less value, but are nevertheless stunning gemstones.

Besides its use in jewelry, topaz has industrial applications. For example, it’s used as a refractory material in kilns and furnaces because it maintains its strength under extreme heat. That property also makes it useful as a mold for molten glass and metals.

Brazil is the largest producer of topaz, the most notable source being the Minas Geranis region. Also, Topaz is mined in several countries including Pakistan, Sri Lanka, Russia and Australia. And in the United States, people have found it in Utah, Texas and California.

Topaz lore

The gemstone’s name, topaz, may have originated from the Sanskrit word meaning fire. However, there’s also a more convoluted alternate story. The gemstone’s name might be from an ancient Greek island in the Red Sea called Topazos. The island, supposedly difficult to locate, was where people mined a yellow stone. Most now think that stone is actually chrysolite.

In ancient lore, topaz had the power to cool boiling water. Supposedly, these gemstones made their owners cheerful, giving them pleasant dreams. People also believed that those who wore topaz would have a long life with beauty and intelligence.

During the Middle Ages, people believed that gemstones with special engravings held great powers. The 13th century “Book of Wings” by Ragiel said about the topaz:

The figure of a falcon, if on a topaz, helps to acquire the goodwill of kings, princes, and magnates.

As medication, people tried to cure fevers with topaz. They added powdered topaz to wine to prevent asthma and insomnia. They believed that a topaz held in the hand of a woman during childbirth lessened her pain.

Saint Hildegard, a 12th century German Benedictine abbess, recommended topaz as a cure for weak vision. People immersed the stone in wine for three days and nights, then rubbed the liquid on the eyes. A 15th century Roman physician claimed to have cured plague sores by touching them with a topaz that once belonged to two Catholic popes.

A chunk of clear light blue topaz, a natural crystal with flat sides.
Blue topaz from Zimbabwe. The rock measures about 1.4 x 1.1 x 1 inches (3.5 x 2.8 x 2.5 cm). Image via Robert M. Lavinsky/ Wikimedia Commons.

Citrine is another choice

Yellow citrine is one of the many colors found in the quartz family. Citrine colors range from a pale yellow to reddish-orange to brown. Occasionally, citrine is a yellow-green color. Its coloring agent is iron. Also, natural citrine is rare, so most citrines you find in jewelry are heat-treated smoky quartz or amethyst.

Even though yellow topaz and citrine look alike visually, they have a different rating on the Mohs hardness scale. Topaz is slightly a harder gemstone than citrine rated at 8 on the Mohs scale, and citrine is a 7. Other yellow gemstones include golden beryl and tourmaline.

A unique gemstone – ametrine – is sometimes unearthed. It’s a mixture of citrine and amethyst occurring in the same crystal. It is especially attractive when both the yellow and purple are vibrant and the split is down the middle of the gemstone.

A faceted rectangular gemstone purple at one end fading into yellow at the other end.
A combination of 2 forms of quartz – citrine and amethyst – called ametrine. Image via Wikimedia Commons.

Brazil produces the most citrine. Citrine is also found in Madagascar, the United States, Argentina, Myanmar, Namibia, Russia, Scotland and Spain.

Two pointed, hexagonal natural crystals of a transparent yellow gemstone.
Citrine crystals. Image via Parent Géry/ Wikimedia Commons.

History of citrine

Citrine comes from the Latin word citrina which means “yellow”.

Using citrine as a gemstone began in Greece starting about 300 BCE, during the Hellenistic Age. Since citrine was associated with prosperity, it is also called the “merchant’s stone” or the “money stone.”

See the birthstones for the rest of the year

January birthstone
February birthstone
March birthstone
April birthstone
May birthstone
June birthstone
July birthstone
August birthstone
September birthstone
October birthstone
November birthstone
December birthstone

Bottom line: Topaz and citrine are the November birthstones. Topaz is a hard mineral popular in jewelry, with an enduring mythology of magical and healing powers. Citrine is a member of the quartz family. So November babies have some colorful choices for their birthstone.

The post November birthstone: Choose from either topaz or citrine first appeared on EarthSky.



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November birthstone: Two golden colored, transparent colored gemstones, one a natural crystal and one faceted.
A natural topaz crystal and a faceted topaz. Topaz is 1 of the 2 options for the November birthstone. The other choice is citrine. Image via Didier Descouens/ Wikipedia.

Topaz, a November birthstone

Topaz, one of two November birthstones, an exquisite gem of many colors, is a much sought-after gemstone for jewelry. In ancient times, people believed that topaz possessed magical and healing qualities. Its name may originate from the Sanskrit word for fire.

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

Colors of topaz

Topaz occurs in a range of magnificent colors: pale blue, pink, red, brown, varying shades of yellow, and even black. However, pure topaz itself is a colorless stone. Some red and some pink topazes get their colors from chromium atoms in the crystal. Most other colors occur due to minor element substitutions and defects in the crystal. However, some colors are unstable and can fade away. Heat can cause color changes. But high-energy irradiation of colorless topaz can transform it to blue gemstones.

Chemically, topaz is an aluminum silicate mineral containing fluorine and hydroxide (a hydrogen-oxygen molecule). Strong chemical bonds within topaz make it the hardest of silicate minerals, rating 8 on the Mohs scale. According to Geoscience Australia, high concentrations of fluorine — a condition needed for topaz formation — are geologically rare. They explained that topaz forms in cavities in certain igneous rocks:

The crystals grow in the late stages of a magma cooling, when there is enough fluorine to enable the formation of topaz. Some topaz crystals grow after hot fluids (hydrothermal solutions), rich in fluorine, flow through cracks in rocks that have already cooled.

Glittering faceted gemstones in several colors: round, oval, square, and triangular.
Different colors of topaz. Image via Michelle Jo/ Wikipedia.

Topaz on display

Topaz gemstones occur in many sizes, from tiny crystals to large rocks. For example, one of the biggest uncut topaz stones, a specimen from Brazil, weighs almost 600 pounds (270 kg). It’s on display at the American Museum of Natural History in New York.

And one of the largest cut topazes in the world – the American Golden Topaz – resides at the Smithsonian Museum of Natural History in Washington, D.C. It weighs 10.1 pounds (4.6 kg) and is about 7 inches (18 cm) in length.

Uses for topaz

The lively fire, clarity, colors and hardness of topaz make it ideal for jewelry such as necklaces, brooches and bracelets. People sometimes mistake colorless pure topaz for a diamond. Because of its rarity, topaz is an expensive gem. The most valued and rarest color is red. Imperial topaz — sherry-colored varieties of brownish-yellow, orange-yellow and reddish brown — are the most popular topaz stones. They command high prices, as do pink stones. Light blue and pale yellow topazes are of less value, but are nevertheless stunning gemstones.

Besides its use in jewelry, topaz has industrial applications. For example, it’s used as a refractory material in kilns and furnaces because it maintains its strength under extreme heat. That property also makes it useful as a mold for molten glass and metals.

Brazil is the largest producer of topaz, the most notable source being the Minas Geranis region. Also, Topaz is mined in several countries including Pakistan, Sri Lanka, Russia and Australia. And in the United States, people have found it in Utah, Texas and California.

Topaz lore

The gemstone’s name, topaz, may have originated from the Sanskrit word meaning fire. However, there’s also a more convoluted alternate story. The gemstone’s name might be from an ancient Greek island in the Red Sea called Topazos. The island, supposedly difficult to locate, was where people mined a yellow stone. Most now think that stone is actually chrysolite.

In ancient lore, topaz had the power to cool boiling water. Supposedly, these gemstones made their owners cheerful, giving them pleasant dreams. People also believed that those who wore topaz would have a long life with beauty and intelligence.

During the Middle Ages, people believed that gemstones with special engravings held great powers. The 13th century “Book of Wings” by Ragiel said about the topaz:

The figure of a falcon, if on a topaz, helps to acquire the goodwill of kings, princes, and magnates.

As medication, people tried to cure fevers with topaz. They added powdered topaz to wine to prevent asthma and insomnia. They believed that a topaz held in the hand of a woman during childbirth lessened her pain.

Saint Hildegard, a 12th century German Benedictine abbess, recommended topaz as a cure for weak vision. People immersed the stone in wine for three days and nights, then rubbed the liquid on the eyes. A 15th century Roman physician claimed to have cured plague sores by touching them with a topaz that once belonged to two Catholic popes.

A chunk of clear light blue topaz, a natural crystal with flat sides.
Blue topaz from Zimbabwe. The rock measures about 1.4 x 1.1 x 1 inches (3.5 x 2.8 x 2.5 cm). Image via Robert M. Lavinsky/ Wikimedia Commons.

Citrine is another choice

Yellow citrine is one of the many colors found in the quartz family. Citrine colors range from a pale yellow to reddish-orange to brown. Occasionally, citrine is a yellow-green color. Its coloring agent is iron. Also, natural citrine is rare, so most citrines you find in jewelry are heat-treated smoky quartz or amethyst.

Even though yellow topaz and citrine look alike visually, they have a different rating on the Mohs hardness scale. Topaz is slightly a harder gemstone than citrine rated at 8 on the Mohs scale, and citrine is a 7. Other yellow gemstones include golden beryl and tourmaline.

A unique gemstone – ametrine – is sometimes unearthed. It’s a mixture of citrine and amethyst occurring in the same crystal. It is especially attractive when both the yellow and purple are vibrant and the split is down the middle of the gemstone.

A faceted rectangular gemstone purple at one end fading into yellow at the other end.
A combination of 2 forms of quartz – citrine and amethyst – called ametrine. Image via Wikimedia Commons.

Brazil produces the most citrine. Citrine is also found in Madagascar, the United States, Argentina, Myanmar, Namibia, Russia, Scotland and Spain.

Two pointed, hexagonal natural crystals of a transparent yellow gemstone.
Citrine crystals. Image via Parent Géry/ Wikimedia Commons.

History of citrine

Citrine comes from the Latin word citrina which means “yellow”.

Using citrine as a gemstone began in Greece starting about 300 BCE, during the Hellenistic Age. Since citrine was associated with prosperity, it is also called the “merchant’s stone” or the “money stone.”

See the birthstones for the rest of the year

January birthstone
February birthstone
March birthstone
April birthstone
May birthstone
June birthstone
July birthstone
August birthstone
September birthstone
October birthstone
November birthstone
December birthstone

Bottom line: Topaz and citrine are the November birthstones. Topaz is a hard mineral popular in jewelry, with an enduring mythology of magical and healing powers. Citrine is a member of the quartz family. So November babies have some colorful choices for their birthstone.

The post November birthstone: Choose from either topaz or citrine first appeared on EarthSky.



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Could the Taurid meteors bring a risk of airbursts in 2026?

A streak of colored light coming from the upper right and expanding near the bottom.
This animation doesn’t illustrate a real impact from space. It’s a simulation, showing a hypothetical impact of an asteroid impact over Denver, Colorado, on a hypothetical future date: April 28, 2027. Physicist Mark Boslough — an expert in planetary defense — said: “The blue pinprick is the first step of my simulation of an asteroid descending over Denver … ” This image was from a 2019 NASA conference on planetary defense.

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

Could Taurid meteors bring an airburst in 2026?

Last year, we told you about a new study suggesting the yearly Taurid meteor shower — and its associated Halloween fireballs — might bring an increased risk of an airburst in 2032 and 2036. The lead author of that study, physicist and planetary defense expert Mark Boslough of the University of New Mexico, contacted EarthSky this week.

His new calculations now suggest a risk of airburst from the Taurids in 2026. But he says the possibility rests on two big, unproven assumptions. Let’s dive in.

In the 2025 study, researchers described a hypothetical swarm of larger objects within the Taurid meteor stream. The study suggested Earth could pass near this swarm in 2032 and 2036, potentially increasing the risk of an airburst in our atmosphere. What’s an airburst? It’s an explosion in Earth’s atmosphere caused by an incoming space rock. The most famous airburst happened in the Tunguska region of Siberia in 1908. And the Chelyabinsk meteor in 2013 — which broke windows in six Russian cities — was also an airburst.

Boslough has now outlined a more speculative possibility: Could more Taurid objects — related to the famous 1908 Tunguska explosion — still be out there in space? And if so, could they return to Earth’s vicinity in 2026?

Tunguska and the Taurids

The Tunguska event flattened forestland in Siberia. Scientists say it happened when a space rock created an airburst in the atmosphere. And some researchers have linked the Tunguska event to the Beta Taurids, a daytime meteor shower associated with the same stream of debris that produces the better-known North and South Taurids in October and November.

Boslough’s 2025 study related to hypothetical objects — associated with the Taurid meteor stream — that might be in an resonance orbit with Earth. An orbital resonance is two orbiting bodies whose orbital periods are related by some ratio.

In other words, was the object that created the Tunguska event a solitary object in space? Or was it part of a cluster of objects, which in turn are associated with the well-known Taurid meteor shower? And if so are there still objects out there in space in a resonance orbit with Earth — an orbit that will bring them back to our vicinity?

We don’t know the answers to these questions. But Boslough estimates that — if they exist — such objects would orbit the sun 18 times for every 61 Earth orbits (an 18:61 resonance orbit with Earth).

So if the Tunguska object did belong to a cluster of debris in that particular resonance orbit, then the cluster — perhaps containing objects big enough to create another airburst — might return to Earth’s vicinity every 61 years. 1908 + 61 = 1969. And 1969 + 61 = 2030. So what does that mean for 2026?

Mark Boslough told EarthSky that, yes, an object in a 61-year resonance orbit would return in June 1930. But, he said:

So imagine if the Tunguska object had missed the Earth in 1908. Then it could return in 2030.  The Halloween 2026 date is significant because the same resonance that creates a close June encounter in 2030 creates a close encounter around Halloween, four years earlier (2026). 

…The good thing about the Taurid resonant swarm hypothesis is that it’s testable. And we will know for sure in 2032 if it really exists.

Of course, these are all events based on hypotheticals. As Boslough told EarthSky, this might only happen:

…IF the Tunguska object was part of a cluster, and IF it had the same orbital elements as the hypothetical swarm (both are big ifs). I will be the first to caution that this is highly speculative because of those two big IFs. We do not know if either are true.

Read on for more insight from the 2025 study.

Halloween fireballs

The term Halloween fireballs refers to the unusually bright meteors (fireballs) produced in some years (but not all years) by the Taurid meteor shower. This shower peaks every year in late October and early November. So if you’re a meteor watcher, there’s a good chance you’ve seen a Halloween fireball already.

Most meteor showers come from comets. When a comet comes in toward the sun, it warms up and releases a trail of debris – dust particles and rocks – along its path. Earth frequently crosses comet paths in its own orbit around the sun. The bits of comet dust and rock enter our atmosphere and burn up due to friction with the air … and voila! We have a meteor shower.

The Taurid shower is a bit different. Astronomers believe it might be the result of a large object that broke up, creating Comet Encke and several asteroids. And scientists think that one of those asteroids – 2004 TG10 – is the parent to the Taurid meteor shower. This asteroid, which the Spacewatch program discovered on October 8, 2004, has an orbit that matches Comet Encke.

And there are multiple Taurid meteor showers. The South and North Taurids are November meteor showers, and the Beta Taurids in June are a daylight shower. They are all associated with Comet Encke and its debris.

Do the Taurid fireballs suggest larger-sized objects moving within the Taurid meteor stream? Some astronomers have even suggested there could be large asteroids hiding in the Taurid stream. But we don’t know if that’s the case.

A matter of planetary defense

Still, it’s a possibility we have to take seriously. Astronomer Mark Boslough said that investigating the possibility of the Taurid meteors producing airbursts is a matter of planetary defense. That’s because, in the past, airbursts have wreaked havoc on the ground.

Boslough said:

Planetary defense is the multidisciplinary and internationally coordinated effort to protect the Earth and its inhabitants from impacts by near-Earth objects. It requires surveys to discover and track near-Earth objects, campaigns to characterize those that are hazardous, modeling efforts to understand and predict impact effects and associated consequences, and mitigation through impact avoidance and/or civil defense.

Researching the Halloween fireballs

The researchers looked at observational data on the Taurid meteors. They found:

… the risk from airburst-sized near-Earth objects, which are small enough to explode in the atmosphere instead of striking the ground, might be larger than currently estimated.

The debris that lights up the Taurid meteors or Halloween fireballs is in harmony with Jupiter’s orbit. For every seven orbits of the sun the debris stream makes, Jupiter makes two orbits. This puts it in resonance with Jupiter. So part of its stream approaches Jupiter at regular intervals. And Jupiter’s large gravity might help organize that stream into dense clusters. The researchers said if Jupiter is indeed having this affect on the swarm, Earth could pass near these denser clusters in 2032 and 2036.

Thus we have the increased risk of airbursts in Earth’s atmosphere.

Halloween fireballs: A man in a long-sleeve orange shirt and khaki pants standing in the desert holding a camera.
Mark Boslough of the University of New Mexico is the lead author of the new paper. Image via UNM.

Bottom line: A researcher from the University of New Mexico said the Taurid meteor shower could bring an increased risk of an airburst in 2026. But it’s based on some pretty big IFs.

Source of the 2025 study: 2032 and 2036 risk enhancement from NEOs in the Taurid stream: Is there a significant coherent component to impact risk?

Via University of New Mexico

The post Could the Taurid meteors bring a risk of airbursts in 2026? first appeared on EarthSky.



from EarthSky https://ift.tt/6r0VLsN
A streak of colored light coming from the upper right and expanding near the bottom.
This animation doesn’t illustrate a real impact from space. It’s a simulation, showing a hypothetical impact of an asteroid impact over Denver, Colorado, on a hypothetical future date: April 28, 2027. Physicist Mark Boslough — an expert in planetary defense — said: “The blue pinprick is the first step of my simulation of an asteroid descending over Denver … ” This image was from a 2019 NASA conference on planetary defense.

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

Could Taurid meteors bring an airburst in 2026?

Last year, we told you about a new study suggesting the yearly Taurid meteor shower — and its associated Halloween fireballs — might bring an increased risk of an airburst in 2032 and 2036. The lead author of that study, physicist and planetary defense expert Mark Boslough of the University of New Mexico, contacted EarthSky this week.

His new calculations now suggest a risk of airburst from the Taurids in 2026. But he says the possibility rests on two big, unproven assumptions. Let’s dive in.

In the 2025 study, researchers described a hypothetical swarm of larger objects within the Taurid meteor stream. The study suggested Earth could pass near this swarm in 2032 and 2036, potentially increasing the risk of an airburst in our atmosphere. What’s an airburst? It’s an explosion in Earth’s atmosphere caused by an incoming space rock. The most famous airburst happened in the Tunguska region of Siberia in 1908. And the Chelyabinsk meteor in 2013 — which broke windows in six Russian cities — was also an airburst.

Boslough has now outlined a more speculative possibility: Could more Taurid objects — related to the famous 1908 Tunguska explosion — still be out there in space? And if so, could they return to Earth’s vicinity in 2026?

Tunguska and the Taurids

The Tunguska event flattened forestland in Siberia. Scientists say it happened when a space rock created an airburst in the atmosphere. And some researchers have linked the Tunguska event to the Beta Taurids, a daytime meteor shower associated with the same stream of debris that produces the better-known North and South Taurids in October and November.

Boslough’s 2025 study related to hypothetical objects — associated with the Taurid meteor stream — that might be in an resonance orbit with Earth. An orbital resonance is two orbiting bodies whose orbital periods are related by some ratio.

In other words, was the object that created the Tunguska event a solitary object in space? Or was it part of a cluster of objects, which in turn are associated with the well-known Taurid meteor shower? And if so are there still objects out there in space in a resonance orbit with Earth — an orbit that will bring them back to our vicinity?

We don’t know the answers to these questions. But Boslough estimates that — if they exist — such objects would orbit the sun 18 times for every 61 Earth orbits (an 18:61 resonance orbit with Earth).

So if the Tunguska object did belong to a cluster of debris in that particular resonance orbit, then the cluster — perhaps containing objects big enough to create another airburst — might return to Earth’s vicinity every 61 years. 1908 + 61 = 1969. And 1969 + 61 = 2030. So what does that mean for 2026?

Mark Boslough told EarthSky that, yes, an object in a 61-year resonance orbit would return in June 1930. But, he said:

So imagine if the Tunguska object had missed the Earth in 1908. Then it could return in 2030.  The Halloween 2026 date is significant because the same resonance that creates a close June encounter in 2030 creates a close encounter around Halloween, four years earlier (2026). 

…The good thing about the Taurid resonant swarm hypothesis is that it’s testable. And we will know for sure in 2032 if it really exists.

Of course, these are all events based on hypotheticals. As Boslough told EarthSky, this might only happen:

…IF the Tunguska object was part of a cluster, and IF it had the same orbital elements as the hypothetical swarm (both are big ifs). I will be the first to caution that this is highly speculative because of those two big IFs. We do not know if either are true.

Read on for more insight from the 2025 study.

Halloween fireballs

The term Halloween fireballs refers to the unusually bright meteors (fireballs) produced in some years (but not all years) by the Taurid meteor shower. This shower peaks every year in late October and early November. So if you’re a meteor watcher, there’s a good chance you’ve seen a Halloween fireball already.

Most meteor showers come from comets. When a comet comes in toward the sun, it warms up and releases a trail of debris – dust particles and rocks – along its path. Earth frequently crosses comet paths in its own orbit around the sun. The bits of comet dust and rock enter our atmosphere and burn up due to friction with the air … and voila! We have a meteor shower.

The Taurid shower is a bit different. Astronomers believe it might be the result of a large object that broke up, creating Comet Encke and several asteroids. And scientists think that one of those asteroids – 2004 TG10 – is the parent to the Taurid meteor shower. This asteroid, which the Spacewatch program discovered on October 8, 2004, has an orbit that matches Comet Encke.

And there are multiple Taurid meteor showers. The South and North Taurids are November meteor showers, and the Beta Taurids in June are a daylight shower. They are all associated with Comet Encke and its debris.

Do the Taurid fireballs suggest larger-sized objects moving within the Taurid meteor stream? Some astronomers have even suggested there could be large asteroids hiding in the Taurid stream. But we don’t know if that’s the case.

A matter of planetary defense

Still, it’s a possibility we have to take seriously. Astronomer Mark Boslough said that investigating the possibility of the Taurid meteors producing airbursts is a matter of planetary defense. That’s because, in the past, airbursts have wreaked havoc on the ground.

Boslough said:

Planetary defense is the multidisciplinary and internationally coordinated effort to protect the Earth and its inhabitants from impacts by near-Earth objects. It requires surveys to discover and track near-Earth objects, campaigns to characterize those that are hazardous, modeling efforts to understand and predict impact effects and associated consequences, and mitigation through impact avoidance and/or civil defense.

Researching the Halloween fireballs

The researchers looked at observational data on the Taurid meteors. They found:

… the risk from airburst-sized near-Earth objects, which are small enough to explode in the atmosphere instead of striking the ground, might be larger than currently estimated.

The debris that lights up the Taurid meteors or Halloween fireballs is in harmony with Jupiter’s orbit. For every seven orbits of the sun the debris stream makes, Jupiter makes two orbits. This puts it in resonance with Jupiter. So part of its stream approaches Jupiter at regular intervals. And Jupiter’s large gravity might help organize that stream into dense clusters. The researchers said if Jupiter is indeed having this affect on the swarm, Earth could pass near these denser clusters in 2032 and 2036.

Thus we have the increased risk of airbursts in Earth’s atmosphere.

Halloween fireballs: A man in a long-sleeve orange shirt and khaki pants standing in the desert holding a camera.
Mark Boslough of the University of New Mexico is the lead author of the new paper. Image via UNM.

Bottom line: A researcher from the University of New Mexico said the Taurid meteor shower could bring an increased risk of an airburst in 2026. But it’s based on some pretty big IFs.

Source of the 2025 study: 2032 and 2036 risk enhancement from NEOs in the Taurid stream: Is there a significant coherent component to impact risk?

Via University of New Mexico

The post Could the Taurid meteors bring a risk of airbursts in 2026? first appeared on EarthSky.



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Daylight Time ends Sunday: 7 tips to help you adjust

Daylight time ends: Closeup of the face of a soundly sleeping baby.
Daylight Time ends Sunday, November 1, 2026. You can sleep like a baby one hour longer! Image via Joni Stewart. Used with permission.

Daylight Time ends

Are you a fan of daylight saving time? Like it or not, the U.S. and parts of Canada continue to use daylight saving time. So at 2 a.m. on Sunday, November 1, 2026, clocks in most U.S. states and select Canadian provinces are due to be turned back one hour (European countries already changed last weekend). So, fall back, clock-watchers!

And, once again, Daylight Time ends for many of us. It’ll begin again on Sunday, March 14, 2027.

That’s unless the U.S. Senate passes the sunshine protection act before then.

The memory tool for your clocks is spring forward, fall back. Easy to do with clocks. Less easy – for many – with our own bodies. According to WebMD, in general, “gaining” an hour in the fall is easier than “losing” an hour in the spring. But many report feeling groggy or off-kilter in the week following both the spring and fall time changes.

Didn’t the U.S. Congress vote on to change that before?

As you may remember, a bill to make daylight saving time permanent was passed by the U.S. Senate in 2022. However, it was never voted on by the U.S. House of Representatives.

Then the bill was introduced again in 2023. But according to Reuters:

The legislation, introduced by a bipartisan group of senators, was passed by the Senate in 2022 but stalled in the U.S. House of Representatives because lawmakers could not agree on whether to keep standard time or permanent daylight saving time.

And now in 2026, another bill is waiting to be voted on by the U.S. Senate. No one can agree on what to do about daylight saving time.

So in the meantime …

Here’s 7 tips to help you adjust

Here are some tips that might help you adjust, mostly adapted from a November 4, 2022, post by the American Academy of Sleep Medicine:

  1. Get at least seven hours of sleep (for adults) or eight hours of sleep (for teens) per night before and after the time change. You can use the American Academy of Sleep Medicine’s bedtime calculator to identify an appropriate nightly bedtime.
  2. Gradually adjust your sleep and wake times. Shift your bedtime 15 to 20 minutes earlier each night for a few nights before the spring time change, or 15 to 20 minutes later each night for a few nights before the fall time change. (If you are experiencing chronic insufficient sleep, you should avoid shifting your bedtime later before the fall time change; you will benefit from getting an “extra” hour of sleep on the night when you “fall back” to standard time.)
  3. Adjust other daily routines – such as mealtimes – to match your new schedule prior to the time change.
  4. Set your clocks to the new time on Saturday evening, and go to bed at your normal bedtime.
  5. Use light and darkness to help your body adjust. In the spring, head outside for some sunlight on Sunday morning and dim the lights in the evening. In the fall, minimize light exposure until your target morning wake time.
  6. Adjusting your exposure to light and darkness will help set your body clock, which regulates the timing of sleep and alertness.
  7. Get plenty of sleep on Sunday night to ensure you’re rested and ready for the week ahead.

Good luck!

Bottom line: Daylight Time ends on November 1, 2026, in North America. Here are seven tips from the American Academy of Sleep Medicine to help you adjust.

The post Daylight Time ends Sunday: 7 tips to help you adjust first appeared on EarthSky.



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Daylight time ends: Closeup of the face of a soundly sleeping baby.
Daylight Time ends Sunday, November 1, 2026. You can sleep like a baby one hour longer! Image via Joni Stewart. Used with permission.

Daylight Time ends

Are you a fan of daylight saving time? Like it or not, the U.S. and parts of Canada continue to use daylight saving time. So at 2 a.m. on Sunday, November 1, 2026, clocks in most U.S. states and select Canadian provinces are due to be turned back one hour (European countries already changed last weekend). So, fall back, clock-watchers!

And, once again, Daylight Time ends for many of us. It’ll begin again on Sunday, March 14, 2027.

That’s unless the U.S. Senate passes the sunshine protection act before then.

The memory tool for your clocks is spring forward, fall back. Easy to do with clocks. Less easy – for many – with our own bodies. According to WebMD, in general, “gaining” an hour in the fall is easier than “losing” an hour in the spring. But many report feeling groggy or off-kilter in the week following both the spring and fall time changes.

Didn’t the U.S. Congress vote on to change that before?

As you may remember, a bill to make daylight saving time permanent was passed by the U.S. Senate in 2022. However, it was never voted on by the U.S. House of Representatives.

Then the bill was introduced again in 2023. But according to Reuters:

The legislation, introduced by a bipartisan group of senators, was passed by the Senate in 2022 but stalled in the U.S. House of Representatives because lawmakers could not agree on whether to keep standard time or permanent daylight saving time.

And now in 2026, another bill is waiting to be voted on by the U.S. Senate. No one can agree on what to do about daylight saving time.

So in the meantime …

Here’s 7 tips to help you adjust

Here are some tips that might help you adjust, mostly adapted from a November 4, 2022, post by the American Academy of Sleep Medicine:

  1. Get at least seven hours of sleep (for adults) or eight hours of sleep (for teens) per night before and after the time change. You can use the American Academy of Sleep Medicine’s bedtime calculator to identify an appropriate nightly bedtime.
  2. Gradually adjust your sleep and wake times. Shift your bedtime 15 to 20 minutes earlier each night for a few nights before the spring time change, or 15 to 20 minutes later each night for a few nights before the fall time change. (If you are experiencing chronic insufficient sleep, you should avoid shifting your bedtime later before the fall time change; you will benefit from getting an “extra” hour of sleep on the night when you “fall back” to standard time.)
  3. Adjust other daily routines – such as mealtimes – to match your new schedule prior to the time change.
  4. Set your clocks to the new time on Saturday evening, and go to bed at your normal bedtime.
  5. Use light and darkness to help your body adjust. In the spring, head outside for some sunlight on Sunday morning and dim the lights in the evening. In the fall, minimize light exposure until your target morning wake time.
  6. Adjusting your exposure to light and darkness will help set your body clock, which regulates the timing of sleep and alertness.
  7. Get plenty of sleep on Sunday night to ensure you’re rested and ready for the week ahead.

Good luck!

Bottom line: Daylight Time ends on November 1, 2026, in North America. Here are seven tips from the American Academy of Sleep Medicine to help you adjust.

The post Daylight Time ends Sunday: 7 tips to help you adjust first appeared on EarthSky.



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Halloween is an astronomy holiday. It’s a cross-quarter day

Halloween: A giant full moon on horizon with small, silhouetted man holding a jack-o-lantern.
View at EarthSky Community Photos. | Stojan Stojanovski in Debrca, Macedonia, caught this wonderful image on Halloween night in 2020, when there was a full moon. Thank you, Stojan! By the way, the next full moon on Halloween will be in 2039.

Halloween is a cross-quarter day

Sure, Halloween is the modern-day descendant of Samhain, a sacred festival of the ancient Celts and Druids in the British Isles. And, yes, Halloween is short for All Hallows’ Eve. But, at its heart, Halloween is an astronomy holiday, rooted in Earth’s orbit around the sun.

That’s because Halloween is a cross-quarter day, and a testament to our ancestors’ deep understanding of the sky. Cross-quarter days fall more or less midway between the equinoxes (when the sun sets due west) and solstices (when the sun sets at its most northern or southern point on the horizon). Halloween — October 31 — is approximately midway between our September equinox and December solstice.

In other words, in traditional astronomy, there are eight major seasonal subdivisions of every year. They include the March and September equinoxes, the June and December solstices and the intervening four cross-quarter days.

In modern times, the four cross-quarter days are often called Groundhog Day (February 2), May Day (May 1), Lammas (August 1) and Halloween (October 31).

Halloween falls at a dark time of year

For those of us in the Northern Hemisphere, Halloween is the darkest of the cross-quarter days. And it comes at a time of year when the days are growing shorter. Early people once said that the spirits of the dead wander from sunset until midnight around this cross-quarter day. After midnight – on November 1, now called All Saints’ Day – the ghosts supposedly go back to rest.

The October 31 date for Halloween is fixed by tradition. The true cross-quarter day falls on November 7, representing a discrepancy of about a week. According to the ancient Celts, a cross-quarter day marks the beginning – not the middle – of a season.

Diagram of Earth's orbit with equinoxes, solstices, and cross-quarter days marked.
Equinoxes, solstices and cross-quarter days are all hallmarks of Earth’s orbit around the sun. Halloween is the 4th cross-quarter day of the year. Illustration via NASA.

The Pleiades connection

Some believe that an early forebear of Halloween – Samhain – happened on the night that the Pleiades star cluster culminated at midnight.

In other words, the Pleiades climbed to its highest point in the sky at midnight on or near the same date as this cross-quarter day. Now, the midnight culmination of the Pleiades cluster occurs on November 21, but Halloween is fixed on October 31.

Presuming the supposed connection between Samhain and the midnight culmination of the Pleiades, the two events took place on or near the same date in the 11th century CE (1001-1100) and 12th century (1101-1200). This was several centuries before the introduction of the Gregorian calendar.

At that time, when the Julian calendar was in use, the cross-quarter day and the midnight culmination of the Pleiades fell – amazingly enough – on or near October 31. But, then, the Julian calendar was about one week out of step with the seasons. Had the Gregorian calendar been in use back then, the date of the cross-quarter day celebration would have been November 7.

A large area of electric blue nebulosity with bright white stars immersed within.
View at EarthSky Community Photos. | Chicky Leclair in Helotes, Texas, completed this long exposure of the Pleiades star cluster on December 25, 2025. Thank you, Chicky!

Bottom line: October 31, the date for Halloween, marks the approximate midway point between the September equinox and the December solstice. So Halloween is an astronomy holiday, and one of the year’s four cross-quarter days.

Read about another cross-quarter day, Groundhog Day

May Day is a cross-quarter day

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

The post Halloween is an astronomy holiday. It’s a cross-quarter day first appeared on EarthSky.



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Halloween: A giant full moon on horizon with small, silhouetted man holding a jack-o-lantern.
View at EarthSky Community Photos. | Stojan Stojanovski in Debrca, Macedonia, caught this wonderful image on Halloween night in 2020, when there was a full moon. Thank you, Stojan! By the way, the next full moon on Halloween will be in 2039.

Halloween is a cross-quarter day

Sure, Halloween is the modern-day descendant of Samhain, a sacred festival of the ancient Celts and Druids in the British Isles. And, yes, Halloween is short for All Hallows’ Eve. But, at its heart, Halloween is an astronomy holiday, rooted in Earth’s orbit around the sun.

That’s because Halloween is a cross-quarter day, and a testament to our ancestors’ deep understanding of the sky. Cross-quarter days fall more or less midway between the equinoxes (when the sun sets due west) and solstices (when the sun sets at its most northern or southern point on the horizon). Halloween — October 31 — is approximately midway between our September equinox and December solstice.

In other words, in traditional astronomy, there are eight major seasonal subdivisions of every year. They include the March and September equinoxes, the June and December solstices and the intervening four cross-quarter days.

In modern times, the four cross-quarter days are often called Groundhog Day (February 2), May Day (May 1), Lammas (August 1) and Halloween (October 31).

Halloween falls at a dark time of year

For those of us in the Northern Hemisphere, Halloween is the darkest of the cross-quarter days. And it comes at a time of year when the days are growing shorter. Early people once said that the spirits of the dead wander from sunset until midnight around this cross-quarter day. After midnight – on November 1, now called All Saints’ Day – the ghosts supposedly go back to rest.

The October 31 date for Halloween is fixed by tradition. The true cross-quarter day falls on November 7, representing a discrepancy of about a week. According to the ancient Celts, a cross-quarter day marks the beginning – not the middle – of a season.

Diagram of Earth's orbit with equinoxes, solstices, and cross-quarter days marked.
Equinoxes, solstices and cross-quarter days are all hallmarks of Earth’s orbit around the sun. Halloween is the 4th cross-quarter day of the year. Illustration via NASA.

The Pleiades connection

Some believe that an early forebear of Halloween – Samhain – happened on the night that the Pleiades star cluster culminated at midnight.

In other words, the Pleiades climbed to its highest point in the sky at midnight on or near the same date as this cross-quarter day. Now, the midnight culmination of the Pleiades cluster occurs on November 21, but Halloween is fixed on October 31.

Presuming the supposed connection between Samhain and the midnight culmination of the Pleiades, the two events took place on or near the same date in the 11th century CE (1001-1100) and 12th century (1101-1200). This was several centuries before the introduction of the Gregorian calendar.

At that time, when the Julian calendar was in use, the cross-quarter day and the midnight culmination of the Pleiades fell – amazingly enough – on or near October 31. But, then, the Julian calendar was about one week out of step with the seasons. Had the Gregorian calendar been in use back then, the date of the cross-quarter day celebration would have been November 7.

A large area of electric blue nebulosity with bright white stars immersed within.
View at EarthSky Community Photos. | Chicky Leclair in Helotes, Texas, completed this long exposure of the Pleiades star cluster on December 25, 2025. Thank you, Chicky!

Bottom line: October 31, the date for Halloween, marks the approximate midway point between the September equinox and the December solstice. So Halloween is an astronomy holiday, and one of the year’s four cross-quarter days.

Read about another cross-quarter day, Groundhog Day

May Day is a cross-quarter day

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

The post Halloween is an astronomy holiday. It’s a cross-quarter day first appeared on EarthSky.



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The Witch Head Nebula rises near Orion on Halloween

Witch Head nebula: Bluish-purple gas cloud in the profile of a witch with pointy nose and chin, in starry space.
The Witch Head Nebula – IC 2118 – lies near the bright star Rigel in Orion the Hunter. This reflection nebula is the perfect complement to the spooky season. Image via NASA/ STScI Digitized Sky Survey/ Noel Carboni.

Witch Head Nebula

It’s that time of year again, when creepy-crawlies and spine-chilling images tickle our imaginations. One of the spookiest views in the night sky is of the Witch Head Nebula, with the catalog designation IC 2118. The Witch Head Nebula is located near Orion‘s brightest star, Rigel. But Rigel is just outside the image above, so the witch gets all the attention. And, if the field of view was large enough to include the blue supergiant star, you could see that the witch appears to be gazing at Rigel.

The constellation Orion, accompanied by the Witch Head Nebula, rises from the eastern horizon before midnight every Halloween. This lengthy nebula spans 70 light-years across and lies 900 light-years from Earth. The nebula is extraordinarily faint, at magnitude 13, so you can only spot it with large telescopes.

Scientists think it might be an ancient supernova remnant. The Witch Head Nebula is categorized as a reflection nebula, or one that shines with the aid of a nearby star. In this case, Rigel shines its bright light on the gas and dust to create the reflection that we see. Basically, the dust reflects more blue light than red, which gives it its eerie purplish-blue hue.

Want to learn how to “capture the witch?” Try this post from the Galactic Hunter.

Want more ghoulish fun? Watch: Halloween Is an astronomy holiday

Some photos from our EarthSky Community

A whitish nebula against a dark, starry sky. The nebula looks like a witch head from the side with a pointy nose.
View at EarthSky Community Photos. | Andy Dungan captured this on October 26, 2025, from Colorado. Andy wrote: “It’s hard to believe 900 light years away is relatively close. This one fascinates me because it really looks like the profile of a witch with a pointy nose. And because it is illuminated by Rigel in Orion. It is thought to be part of a supernova remnant. This picture simply has to be taken prior to Halloween!” Thank you, Andy!
A ghostly nebula resembling witch's head from the side with a starry background and a glowing streak of blue at the top.
EarthSky’s Marcy Curran’s husband captured the Witch Head Nebula on December 2, 2024, from Wyoming. Martin said: “I like the blue glow because it looks like they’re astonished by whatever is out of the frame”. That’s the glow from the bright star Rigel. Thank you, Martin!

And, if you wonder how a witch can get around in the sky … there’s a Witch’s Broom Nebula located in Cygnus.

Streamers of blue and orange nebula resembling an old fashioned broom on a starry sky with a bright star above it.
View at EarthSky Community Photos. | Rui Santos captured this image on July 9, 2025, from Portugal. Rui wrote: “The Western Veil Nebula, in the constellation Cygnus, is part of a supernova remnant. So it’s the remains of a massive star that exploded around 8,000 years ago. It’s about 2,400 light-years from Earth and had nearly 20 times the mass of our sun! The explosion was so powerful that it hurled the star’s outer layers into space at incredibly high speeds. Those formed filament-like structures that glow as they collide with interstellar gas. It’s amazing to think that such a catastrophic event could leave behind something so incredibly beautiful.” It’s also known as the Witch’s Broom. Thank you, Rui!

Bottom line: The Witch Head Nebula rises near the star Rigel in Orion on Halloween night, but you need a telescope to see it.

Read more: Halloween is an astronomy holiday. It’s a cross-quarter day

Read more: Here’s where popular witch icons originated

The post The Witch Head Nebula rises near Orion on Halloween first appeared on EarthSky.



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Witch Head nebula: Bluish-purple gas cloud in the profile of a witch with pointy nose and chin, in starry space.
The Witch Head Nebula – IC 2118 – lies near the bright star Rigel in Orion the Hunter. This reflection nebula is the perfect complement to the spooky season. Image via NASA/ STScI Digitized Sky Survey/ Noel Carboni.

Witch Head Nebula

It’s that time of year again, when creepy-crawlies and spine-chilling images tickle our imaginations. One of the spookiest views in the night sky is of the Witch Head Nebula, with the catalog designation IC 2118. The Witch Head Nebula is located near Orion‘s brightest star, Rigel. But Rigel is just outside the image above, so the witch gets all the attention. And, if the field of view was large enough to include the blue supergiant star, you could see that the witch appears to be gazing at Rigel.

The constellation Orion, accompanied by the Witch Head Nebula, rises from the eastern horizon before midnight every Halloween. This lengthy nebula spans 70 light-years across and lies 900 light-years from Earth. The nebula is extraordinarily faint, at magnitude 13, so you can only spot it with large telescopes.

Scientists think it might be an ancient supernova remnant. The Witch Head Nebula is categorized as a reflection nebula, or one that shines with the aid of a nearby star. In this case, Rigel shines its bright light on the gas and dust to create the reflection that we see. Basically, the dust reflects more blue light than red, which gives it its eerie purplish-blue hue.

Want to learn how to “capture the witch?” Try this post from the Galactic Hunter.

Want more ghoulish fun? Watch: Halloween Is an astronomy holiday

Some photos from our EarthSky Community

A whitish nebula against a dark, starry sky. The nebula looks like a witch head from the side with a pointy nose.
View at EarthSky Community Photos. | Andy Dungan captured this on October 26, 2025, from Colorado. Andy wrote: “It’s hard to believe 900 light years away is relatively close. This one fascinates me because it really looks like the profile of a witch with a pointy nose. And because it is illuminated by Rigel in Orion. It is thought to be part of a supernova remnant. This picture simply has to be taken prior to Halloween!” Thank you, Andy!
A ghostly nebula resembling witch's head from the side with a starry background and a glowing streak of blue at the top.
EarthSky’s Marcy Curran’s husband captured the Witch Head Nebula on December 2, 2024, from Wyoming. Martin said: “I like the blue glow because it looks like they’re astonished by whatever is out of the frame”. That’s the glow from the bright star Rigel. Thank you, Martin!

And, if you wonder how a witch can get around in the sky … there’s a Witch’s Broom Nebula located in Cygnus.

Streamers of blue and orange nebula resembling an old fashioned broom on a starry sky with a bright star above it.
View at EarthSky Community Photos. | Rui Santos captured this image on July 9, 2025, from Portugal. Rui wrote: “The Western Veil Nebula, in the constellation Cygnus, is part of a supernova remnant. So it’s the remains of a massive star that exploded around 8,000 years ago. It’s about 2,400 light-years from Earth and had nearly 20 times the mass of our sun! The explosion was so powerful that it hurled the star’s outer layers into space at incredibly high speeds. Those formed filament-like structures that glow as they collide with interstellar gas. It’s amazing to think that such a catastrophic event could leave behind something so incredibly beautiful.” It’s also known as the Witch’s Broom. Thank you, Rui!

Bottom line: The Witch Head Nebula rises near the star Rigel in Orion on Halloween night, but you need a telescope to see it.

Read more: Halloween is an astronomy holiday. It’s a cross-quarter day

Read more: Here’s where popular witch icons originated

The post The Witch Head Nebula rises near Orion on Halloween first appeared on EarthSky.



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