Corey S. Powell
@coreyspowell.bsky.social
Fascinated by things very big, very small, and beyond the limits of the human senses. Founder of OpenMind: www.openmindmag.org Creator of the Invisible Universe column: https://invisibleuniverse.substack.com/
Pinned
Corey S. Powell
@coreyspowell.bsky.social
· Nov 15
In honor of all the new arrivals, I'm sharing one of my favorite videos.
It shows 24 hours of Earth's rotation, with the camera locked to the sky instead of the ground. We're all hanging out on this spinning rock.
Brilliant work by Bartosz Wojczyński. 🧪
artuniverse.eu/gallery/1907...
It shows 24 hours of Earth's rotation, with the camera locked to the sky instead of the ground. We're all hanging out on this spinning rock.
Brilliant work by Bartosz Wojczyński. 🧪
artuniverse.eu/gallery/1907...
NASA's just-launched ESCAPADE mission is trying out a novel trajectory to Mars, one that's slower but allows much more flexible launch dates. The flight path also provides a bonus science session at the L2 equilibrium point near Earth. 🧪🔭
skyandtelescope.org/astronomy-ne...
skyandtelescope.org/astronomy-ne...
November 14, 2025 at 4:46 PM
NASA's just-launched ESCAPADE mission is trying out a novel trajectory to Mars, one that's slower but allows much more flexible launch dates. The flight path also provides a bonus science session at the L2 equilibrium point near Earth. 🧪🔭
skyandtelescope.org/astronomy-ne...
skyandtelescope.org/astronomy-ne...
Reposted by Corey S. Powell
#3IATLAS update: we've just pinpointed the comet's path with 10 times more accuracy, using data from our #ExoMars Trace Gas Orbiter spacecraft. 😎🧪🔭
www.esa.int/Space_Safety...
www.esa.int/Space_Safety...
November 14, 2025 at 10:25 AM
#3IATLAS update: we've just pinpointed the comet's path with 10 times more accuracy, using data from our #ExoMars Trace Gas Orbiter spacecraft. 😎🧪🔭
www.esa.int/Space_Safety...
www.esa.int/Space_Safety...
My apologies to all: That was an image of Comet K1 ATLAS, not Comet 3I/ATLAS. Sorry about my error. (That's what I get for posting as I'm running out for a beer.)
As noted in the image, this is C/2025 K1 Atlas, an entirely different comet.
en.wikipedia.org/wiki/C/2025_...
Last I checked 3I/Atlas was still in one piece - and still not a spaceship :)
en.wikipedia.org/wiki/C/2025_...
Last I checked 3I/Atlas was still in one piece - and still not a spaceship :)
C/2025 K1 (ATLAS) - Wikipedia
en.wikipedia.org
November 14, 2025 at 12:35 AM
My apologies to all: That was an image of Comet K1 ATLAS, not Comet 3I/ATLAS. Sorry about my error. (That's what I get for posting as I'm running out for a beer.)
Interstellar Comet 3I/ATLAS is fragmenting on its way back out from the Sun. 🧪🔭
www.virtualtelescope.eu/2025/11/13/c...
www.virtualtelescope.eu/2025/11/13/c...
November 13, 2025 at 9:21 PM
Interstellar Comet 3I/ATLAS is fragmenting on its way back out from the Sun. 🧪🔭
www.virtualtelescope.eu/2025/11/13/c...
www.virtualtelescope.eu/2025/11/13/c...
New images of interstellar Comet 3I/ATLAS are coming in as it moves out of the Sun's glare and (barely) back into view.
This shot, by Michael Buechner and Frank Niebling, shows an intriguing anti-tail and a "smoking" tail. 🧪🔭
britastro.org/observations...
This shot, by Michael Buechner and Frank Niebling, shows an intriguing anti-tail and a "smoking" tail. 🧪🔭
britastro.org/observations...
November 12, 2025 at 12:26 AM
New images of interstellar Comet 3I/ATLAS are coming in as it moves out of the Sun's glare and (barely) back into view.
This shot, by Michael Buechner and Frank Niebling, shows an intriguing anti-tail and a "smoking" tail. 🧪🔭
britastro.org/observations...
This shot, by Michael Buechner and Frank Niebling, shows an intriguing anti-tail and a "smoking" tail. 🧪🔭
britastro.org/observations...
I find this remarkable:
The Dresden Codex, one of the few surviving Mayan manuscripts, contains tables that give highly accurate timings of solar eclipses over more than 700 years, from 350 CE to the 12 century. 🧪🔭
www.science.org/doi/10.1126/...
The Dresden Codex, one of the few surviving Mayan manuscripts, contains tables that give highly accurate timings of solar eclipses over more than 700 years, from 350 CE to the 12 century. 🧪🔭
www.science.org/doi/10.1126/...
November 11, 2025 at 12:49 AM
I find this remarkable:
The Dresden Codex, one of the few surviving Mayan manuscripts, contains tables that give highly accurate timings of solar eclipses over more than 700 years, from 350 CE to the 12 century. 🧪🔭
www.science.org/doi/10.1126/...
The Dresden Codex, one of the few surviving Mayan manuscripts, contains tables that give highly accurate timings of solar eclipses over more than 700 years, from 350 CE to the 12 century. 🧪🔭
www.science.org/doi/10.1126/...
Wishing you all a happy Carl Sagan Day (born this day in 1934).
Fascinating to see his note summarizing the key topics he planned to discuss during his 1977 meeting with President Carter. ("Wonder"!) 🧪🔭
www.loc.gov/collections/...
Fascinating to see his note summarizing the key topics he planned to discuss during his 1977 meeting with President Carter. ("Wonder"!) 🧪🔭
www.loc.gov/collections/...
November 10, 2025 at 2:15 AM
Wishing you all a happy Carl Sagan Day (born this day in 1934).
Fascinating to see his note summarizing the key topics he planned to discuss during his 1977 meeting with President Carter. ("Wonder"!) 🧪🔭
www.loc.gov/collections/...
Fascinating to see his note summarizing the key topics he planned to discuss during his 1977 meeting with President Carter. ("Wonder"!) 🧪🔭
www.loc.gov/collections/...
This is what the band of the Milky Way would look like at night if your eyes could see radio waves. A hidden beauty.
It's a new image created by the Murchison Widefield Array, which scanned the sky in 20 radio "colors" over frequencies from 72 to 231 megahertz. 🧪🔭
www.icrar.org/gleam-x-gala...
It's a new image created by the Murchison Widefield Array, which scanned the sky in 20 radio "colors" over frequencies from 72 to 231 megahertz. 🧪🔭
www.icrar.org/gleam-x-gala...
November 9, 2025 at 6:19 PM
This is what the band of the Milky Way would look like at night if your eyes could see radio waves. A hidden beauty.
It's a new image created by the Murchison Widefield Array, which scanned the sky in 20 radio "colors" over frequencies from 72 to 231 megahertz. 🧪🔭
www.icrar.org/gleam-x-gala...
It's a new image created by the Murchison Widefield Array, which scanned the sky in 20 radio "colors" over frequencies from 72 to 231 megahertz. 🧪🔭
www.icrar.org/gleam-x-gala...
Nature makes weird planets, and now this is among the weirdest: As big as Jupiter, made of carbon, blasted by high winds, and heated to 1900 degrees C by a dying, fast-spinning pulsar.
No matter how bad things get here, we live on the best of all possible worlds. 🔭🧪
arxiv.org/abs/2509.04558
No matter how bad things get here, we live on the best of all possible worlds. 🔭🧪
arxiv.org/abs/2509.04558
November 8, 2025 at 1:53 PM
Nature makes weird planets, and now this is among the weirdest: As big as Jupiter, made of carbon, blasted by high winds, and heated to 1900 degrees C by a dying, fast-spinning pulsar.
No matter how bad things get here, we live on the best of all possible worlds. 🔭🧪
arxiv.org/abs/2509.04558
No matter how bad things get here, we live on the best of all possible worlds. 🔭🧪
arxiv.org/abs/2509.04558
Meanwhile on Mars...
The planet is covered with odd gullies that look like they were carved by running water. A cool new experiment demonstrates that they were probably carved by sliding, spitting chunks of dry ice. (Sorry, still no signs of life.) 🧪🔭
www.uu.nl/en/news/myst...
The planet is covered with odd gullies that look like they were carved by running water. A cool new experiment demonstrates that they were probably carved by sliding, spitting chunks of dry ice. (Sorry, still no signs of life.) 🧪🔭
www.uu.nl/en/news/myst...
November 6, 2025 at 11:18 PM
Meanwhile on Mars...
The planet is covered with odd gullies that look like they were carved by running water. A cool new experiment demonstrates that they were probably carved by sliding, spitting chunks of dry ice. (Sorry, still no signs of life.) 🧪🔭
www.uu.nl/en/news/myst...
The planet is covered with odd gullies that look like they were carved by running water. A cool new experiment demonstrates that they were probably carved by sliding, spitting chunks of dry ice. (Sorry, still no signs of life.) 🧪🔭
www.uu.nl/en/news/myst...
Reposted by Corey S. Powell
The X-10 graphite reactor at Oak Ridge went critical #OTD in 1943.
Built as part of the Manhattan Project, it was the second artificial nuclear reactor (after Fermi's Chicago Pile 1) and the first to operate continuously. 🧪 ⚛️
Image: Ed Westcott
Built as part of the Manhattan Project, it was the second artificial nuclear reactor (after Fermi's Chicago Pile 1) and the first to operate continuously. 🧪 ⚛️
Image: Ed Westcott
November 4, 2025 at 7:48 PM
The X-10 graphite reactor at Oak Ridge went critical #OTD in 1943.
Built as part of the Manhattan Project, it was the second artificial nuclear reactor (after Fermi's Chicago Pile 1) and the first to operate continuously. 🧪 ⚛️
Image: Ed Westcott
Built as part of the Manhattan Project, it was the second artificial nuclear reactor (after Fermi's Chicago Pile 1) and the first to operate continuously. 🧪 ⚛️
Image: Ed Westcott
This mysterious object, called Capotauro, might be the earliest, most distant galaxy ever seen, containing some of the universe's first stars.
Or it might be a mundane, nearby brown dwarf floating through our Milky Way.
Nobody said cosmology was easy. 🧪🔭
arxiv.org/abs/2509.016...
Or it might be a mundane, nearby brown dwarf floating through our Milky Way.
Nobody said cosmology was easy. 🧪🔭
arxiv.org/abs/2509.016...
November 4, 2025 at 7:21 PM
This mysterious object, called Capotauro, might be the earliest, most distant galaxy ever seen, containing some of the universe's first stars.
Or it might be a mundane, nearby brown dwarf floating through our Milky Way.
Nobody said cosmology was easy. 🧪🔭
arxiv.org/abs/2509.016...
Or it might be a mundane, nearby brown dwarf floating through our Milky Way.
Nobody said cosmology was easy. 🧪🔭
arxiv.org/abs/2509.016...
You can almost reach out and touch it. What a shot of Comet Lemmon!
Comet A6 Lemmon's closest approach to the Sun is on November 8th, 2025. I took this image on October 29th showing a huge increase in activity around the core. A very zoomed in shot using a 16 inch telescope f/18, 7400mm focal length with Canon R6.
#astrophotography #astronomy #comets #cometlemmon
#astrophotography #astronomy #comets #cometlemmon
November 2, 2025 at 12:07 AM
You can almost reach out and touch it. What a shot of Comet Lemmon!
Astronomers sure do conjure up a lot of spooky images when they look out into deep space. A short Halloween thread:
Let's start with the Cosmic Bat Nebula (LDN 43). 🧪🔭
apod.nasa.gov/apod/ap24102...
Let's start with the Cosmic Bat Nebula (LDN 43). 🧪🔭
apod.nasa.gov/apod/ap24102...
October 31, 2025 at 2:44 PM
Astronomers sure do conjure up a lot of spooky images when they look out into deep space. A short Halloween thread:
Let's start with the Cosmic Bat Nebula (LDN 43). 🧪🔭
apod.nasa.gov/apod/ap24102...
Let's start with the Cosmic Bat Nebula (LDN 43). 🧪🔭
apod.nasa.gov/apod/ap24102...
Fascinating graph shows the estimated total mass of all the mammals living on Earth.
In 1850, it was evenly divided between wildlife and humans + domesticated animals. Today, humans and their livestock account for about 95% of the total. 🧪
www.nature.com/articles/s41...
In 1850, it was evenly divided between wildlife and humans + domesticated animals. Today, humans and their livestock account for about 95% of the total. 🧪
www.nature.com/articles/s41...
October 30, 2025 at 1:58 PM
Fascinating graph shows the estimated total mass of all the mammals living on Earth.
In 1850, it was evenly divided between wildlife and humans + domesticated animals. Today, humans and their livestock account for about 95% of the total. 🧪
www.nature.com/articles/s41...
In 1850, it was evenly divided between wildlife and humans + domesticated animals. Today, humans and their livestock account for about 95% of the total. 🧪
www.nature.com/articles/s41...
Many objects in space have obscure names (HD 219134b) or unhelpful classical names (try to find the dog of Canis Minor, I dare you).
But the Red Spider Nebula really looks like a spider in space--the breath of an old, dying star caught in a web of interstellar gas. 🧪🔭
esawebb.org/images/potm2...
But the Red Spider Nebula really looks like a spider in space--the breath of an old, dying star caught in a web of interstellar gas. 🧪🔭
esawebb.org/images/potm2...
October 29, 2025 at 4:17 PM
Many objects in space have obscure names (HD 219134b) or unhelpful classical names (try to find the dog of Canis Minor, I dare you).
But the Red Spider Nebula really looks like a spider in space--the breath of an old, dying star caught in a web of interstellar gas. 🧪🔭
esawebb.org/images/potm2...
But the Red Spider Nebula really looks like a spider in space--the breath of an old, dying star caught in a web of interstellar gas. 🧪🔭
esawebb.org/images/potm2...
I love this.
If you live anywhere in the dark blue areas, you are closer to outer space (defined by the Kármán line) than you are to the nearest seashore. 🧪
If you live anywhere in the dark blue areas, you are closer to outer space (defined by the Kármán line) than you are to the nearest seashore. 🧪
Space is a lot closer than most people realise
by u/Many-Excitement3246
by u/Many-Excitement3246
October 29, 2025 at 3:37 PM
I love this.
If you live anywhere in the dark blue areas, you are closer to outer space (defined by the Kármán line) than you are to the nearest seashore. 🧪
If you live anywhere in the dark blue areas, you are closer to outer space (defined by the Kármán line) than you are to the nearest seashore. 🧪
Reposted by Corey S. Powell
Thanks to some vigilant friends out there, I have a nearly-complete 87-hour radar loop of #Melissa 's approach to #Jamaica. The loop abruptly ends when the radar is lost (either loss of communication with it or loss of the actual structure).
bmcnoldy.earth.miami.edu/tropics/radar/
bmcnoldy.earth.miami.edu/tropics/radar/
October 29, 2025 at 12:03 PM
Thanks to some vigilant friends out there, I have a nearly-complete 87-hour radar loop of #Melissa 's approach to #Jamaica. The loop abruptly ends when the radar is lost (either loss of communication with it or loss of the actual structure).
bmcnoldy.earth.miami.edu/tropics/radar/
bmcnoldy.earth.miami.edu/tropics/radar/
Spectacular time-lapse image of Comet Lemmon (C/2025 A6), taken by astrophotographer Michael Jäger.
There might have been, um, a few satellites passing by during the long exposure. 🧪🔭
forum.vdsastro.de/viewtopic.ph...
There might have been, um, a few satellites passing by during the long exposure. 🧪🔭
forum.vdsastro.de/viewtopic.ph...
October 28, 2025 at 7:31 PM
Spectacular time-lapse image of Comet Lemmon (C/2025 A6), taken by astrophotographer Michael Jäger.
There might have been, um, a few satellites passing by during the long exposure. 🧪🔭
forum.vdsastro.de/viewtopic.ph...
There might have been, um, a few satellites passing by during the long exposure. 🧪🔭
forum.vdsastro.de/viewtopic.ph...
More space beauty for your day: This new JWST image of Uranus shows exquisite detail in the rings, clouds, and huge polar cap. Imagine what it took to knock this planet on its side.
Processing by Andrea Luck. 🔭🧪
www.flickr.com/photos/19227...
Processing by Andrea Luck. 🔭🧪
www.flickr.com/photos/19227...
October 28, 2025 at 11:54 AM
More space beauty for your day: This new JWST image of Uranus shows exquisite detail in the rings, clouds, and huge polar cap. Imagine what it took to knock this planet on its side.
Processing by Andrea Luck. 🔭🧪
www.flickr.com/photos/19227...
Processing by Andrea Luck. 🔭🧪
www.flickr.com/photos/19227...
What a strange, beautiful shot of Comet Lemmon, now passing through the northwest sky after sunset.
Here you see 2 comet tails (gas and dust), plus the unrelated zigzag trail of a passing meteor. And, inevitably, a couple satellite trails, too. 🧪🔭
star.ucl.ac.uk/~apod/apod/a...
Here you see 2 comet tails (gas and dust), plus the unrelated zigzag trail of a passing meteor. And, inevitably, a couple satellite trails, too. 🧪🔭
star.ucl.ac.uk/~apod/apod/a...
October 28, 2025 at 11:38 AM
What a strange, beautiful shot of Comet Lemmon, now passing through the northwest sky after sunset.
Here you see 2 comet tails (gas and dust), plus the unrelated zigzag trail of a passing meteor. And, inevitably, a couple satellite trails, too. 🧪🔭
star.ucl.ac.uk/~apod/apod/a...
Here you see 2 comet tails (gas and dust), plus the unrelated zigzag trail of a passing meteor. And, inevitably, a couple satellite trails, too. 🧪🔭
star.ucl.ac.uk/~apod/apod/a...
China's Chang'e-6 sample-return mission discovered that the far side of the Moon is covered with fragments of carbonaceous, water-rich meteorites.
Long ago, similar objects may have helped give Earth its oceans & delivered some of the raw materials for life. 🧪🔭
english.cas.cn/newsroom/res...
Long ago, similar objects may have helped give Earth its oceans & delivered some of the raw materials for life. 🧪🔭
english.cas.cn/newsroom/res...
October 27, 2025 at 3:07 PM
China's Chang'e-6 sample-return mission discovered that the far side of the Moon is covered with fragments of carbonaceous, water-rich meteorites.
Long ago, similar objects may have helped give Earth its oceans & delivered some of the raw materials for life. 🧪🔭
english.cas.cn/newsroom/res...
Long ago, similar objects may have helped give Earth its oceans & delivered some of the raw materials for life. 🧪🔭
english.cas.cn/newsroom/res...
This is the most gloriously nerdy thing I've heard in a long time:
My daughter's chem class is celebrating guaca-mole day today, because guaca-mole is made with avogadros.
#iykyk
My daughter's chem class is celebrating guaca-mole day today, because guaca-mole is made with avogadros.
#iykyk
October 23, 2025 at 11:21 PM
This is the most gloriously nerdy thing I've heard in a long time:
My daughter's chem class is celebrating guaca-mole day today, because guaca-mole is made with avogadros.
#iykyk
My daughter's chem class is celebrating guaca-mole day today, because guaca-mole is made with avogadros.
#iykyk
Reposted by Corey S. Powell
Monty Python understood p-hacking
October 23, 2025 at 8:43 AM
Monty Python understood p-hacking
October 23, 2025 at 1:02 PM