Mark Marley
@markmarley.bsky.social
Personal account. Substellar science since the 80s.
Reposted by Mark Marley
With a translation:
This image shows the same star field as Comet C/2025 A6 (Lemmon) without cleaning.
In just 15 minutes of acquisition, we counted 1,659 satellite trails (about 400 individual ones).
Words cannot describe the pollution of near space.
This image shows the same star field as Comet C/2025 A6 (Lemmon) without cleaning.
In just 15 minutes of acquisition, we counted 1,659 satellite trails (about 400 individual ones).
Words cannot describe the pollution of near space.
3/4. En esta imagen se muestra el mismo campo estelar del Cometa C/2025 A6 (Lemmon) sin limpiar.
En solo 15 minutos de adquisición, contamos 1659 trazas de satélites (unos 400 individuales).
Sobran las palabras para describir la contaminación del espacio cercano.
En solo 15 minutos de adquisición, contamos 1659 trazas de satélites (unos 400 individuales).
Sobran las palabras para describir la contaminación del espacio cercano.
November 29, 2025 at 4:22 PM
With a translation:
This image shows the same star field as Comet C/2025 A6 (Lemmon) without cleaning.
In just 15 minutes of acquisition, we counted 1,659 satellite trails (about 400 individual ones).
Words cannot describe the pollution of near space.
This image shows the same star field as Comet C/2025 A6 (Lemmon) without cleaning.
In just 15 minutes of acquisition, we counted 1,659 satellite trails (about 400 individual ones).
Words cannot describe the pollution of near space.
Relatives have an apt license plate for their copper colored car.
November 29, 2025 at 12:01 AM
Relatives have an apt license plate for their copper colored car.
I kind of want to see an equally bad AI solar system science infographic. Like new cubical planets on highly inclined and intersecting orbits or something. Could submit to one of those predatory journals we all get emails from.
Springer-Nature statement
“Whilst the details of peer review are confidential, we can confirm that the article underwent two rounds of review from two independent peer reviewers, supporting an accept decision.”
How am I now expected to believe that two people looked at the paper twice and DGAF?
“Whilst the details of peer review are confidential, we can confirm that the article underwent two rounds of review from two independent peer reviewers, supporting an accept decision.”
How am I now expected to believe that two people looked at the paper twice and DGAF?
Riding the Autism Bicycle to Retraction Town
Does anyone *really* know their Factor Fexcectorn?
nobreakthroughs.substack.com
November 28, 2025 at 2:06 PM
I kind of want to see an equally bad AI solar system science infographic. Like new cubical planets on highly inclined and intersecting orbits or something. Could submit to one of those predatory journals we all get emails from.
Years ago Adam Showman described to me his long term plan to better understand brown dwarf variability by adding more cloud physics to his GCM. Thankful today to be part of team led by his former student Xianyu Tan growing and expanding the vision with this new paper. www.science.org/doi/10.1126/...
Large-amplitude variability driven by giant dust storms on a planetary-mass companion
Global-scale storms composed of silicates and metals explain the extreme weather and variability of the super-Jupiter VHS 1256B.
www.science.org
November 27, 2025 at 2:06 PM
Years ago Adam Showman described to me his long term plan to better understand brown dwarf variability by adding more cloud physics to his GCM. Thankful today to be part of team led by his former student Xianyu Tan growing and expanding the vision with this new paper. www.science.org/doi/10.1126/...
Reposted by Mark Marley
Looking for good news, I found this:
If you were struck by a microscopic black hole, the mass of a small asteroid, it'd be no worse than a gunshot. And such black holes are definitely too rare to have "any observable effects on the human population." 🔭🧪
www.sciencealert.com/what-if-a-ti...
If you were struck by a microscopic black hole, the mass of a small asteroid, it'd be no worse than a gunshot. And such black holes are definitely too rare to have "any observable effects on the human population." 🔭🧪
www.sciencealert.com/what-if-a-ti...
November 27, 2025 at 1:47 AM
Looking for good news, I found this:
If you were struck by a microscopic black hole, the mass of a small asteroid, it'd be no worse than a gunshot. And such black holes are definitely too rare to have "any observable effects on the human population." 🔭🧪
www.sciencealert.com/what-if-a-ti...
If you were struck by a microscopic black hole, the mass of a small asteroid, it'd be no worse than a gunshot. And such black holes are definitely too rare to have "any observable effects on the human population." 🔭🧪
www.sciencealert.com/what-if-a-ti...
I once flew to Kona on a twin aisle aircraft the Sunday after T-day for a conference. Turns out they were flying it almost empty to bring back holiday travelers. Most of the few economy passengers were in the back section of the plane and FA's were strict about staying back for weight & balance. 1/n
November 26, 2025 at 8:04 PM
I once flew to Kona on a twin aisle aircraft the Sunday after T-day for a conference. Turns out they were flying it almost empty to bring back holiday travelers. Most of the few economy passengers were in the back section of the plane and FA's were strict about staying back for weight & balance. 1/n
Reposted by Mark Marley
LPLs HiRISE camera gets a close look at comet from interstellar space. news.arizona.edu/news/u-mars-...
U of A's Mars camera gets close look at comet from interstellar space
HiRISE, a U of A-led Mars imaging camera aboard NASA's Mars Reconnaissance Orbiter, found itself closer than any other imaging tool to comet 3I/ATLAS as it passed through the solar system.
news.arizona.edu
November 20, 2025 at 9:40 PM
LPLs HiRISE camera gets a close look at comet from interstellar space. news.arizona.edu/news/u-mars-...
Reposted by Mark Marley
The OSIRIS-APEX (Origins, Spectral Interpretation, Resource Identification, and Security – Apophis Explorer) spacecraft swung by Earth within 2,136 miles before heading into deep space for another trip around the sun. news.arizona.edu/news/osiris-...
OSIRIS-APEX spacecraft takes selfie with Earth during flyby
The spacecraft of the U of A-led OSIRIS-APEX mission performed a "slingshot" maneuver around Earth as part of its journey to catch up with its mission target, asteroid Apophis.
news.arizona.edu
November 26, 2025 at 6:17 PM
The OSIRIS-APEX (Origins, Spectral Interpretation, Resource Identification, and Security – Apophis Explorer) spacecraft swung by Earth within 2,136 miles before heading into deep space for another trip around the sun. news.arizona.edu/news/osiris-...
Reposted by Mark Marley
In ApJ today, our paper on the early evolution of brown dwarfs, which combines the Sonora brown dwarf and SPHINX M dwarf atmosphere models. Check out this cool plot of giant planet, brown dwarf, and low-mass star radii over time. Work led by UCSC grad Evan Davis.
iopscience.iop.org/article/10.3...
iopscience.iop.org/article/10.3...
November 26, 2025 at 5:48 PM
In ApJ today, our paper on the early evolution of brown dwarfs, which combines the Sonora brown dwarf and SPHINX M dwarf atmosphere models. Check out this cool plot of giant planet, brown dwarf, and low-mass star radii over time. Work led by UCSC grad Evan Davis.
iopscience.iop.org/article/10.3...
iopscience.iop.org/article/10.3...
There were also some excellent Earth as an exoplanet observations conducted. Stay tuned for those.
November 25, 2025 at 5:38 PM
There were also some excellent Earth as an exoplanet observations conducted. Stay tuned for those.
Reposted by Mark Marley
HiRISE Image of Exocomet 3I/ATLAS!
On 2 October 2025, MRO turned away from Mars to image 3I/ATLAS, only the third interstellar object ever observed passing through our solar system!
https://www.uahirise.org/releases/3i-atlas/
On 2 October 2025, MRO turned away from Mars to image 3I/ATLAS, only the third interstellar object ever observed passing through our solar system!
https://www.uahirise.org/releases/3i-atlas/
November 19, 2025 at 9:01 PM
HiRISE Image of Exocomet 3I/ATLAS!
On 2 October 2025, MRO turned away from Mars to image 3I/ATLAS, only the third interstellar object ever observed passing through our solar system!
https://www.uahirise.org/releases/3i-atlas/
On 2 October 2025, MRO turned away from Mars to image 3I/ATLAS, only the third interstellar object ever observed passing through our solar system!
https://www.uahirise.org/releases/3i-atlas/
LPL’s Shane Byrne speaking truth:
“Byrne was less diplomatic. 'It's a bunch of nonsense,' he said, with nothing more to add.”
arizonadailystar-az.newsmemory.com?publink=33a9...
“Byrne was less diplomatic. 'It's a bunch of nonsense,' he said, with nothing more to add.”
arizonadailystar-az.newsmemory.com?publink=33a9...
UA team catches rare interstellar comet on camera
HENRY BREANArizona Daily Star A University of Arizona-led team using a
arizonadailystar-az.newsmemory.com
November 22, 2025 at 4:05 PM
LPL’s Shane Byrne speaking truth:
“Byrne was less diplomatic. 'It's a bunch of nonsense,' he said, with nothing more to add.”
arizonadailystar-az.newsmemory.com?publink=33a9...
“Byrne was less diplomatic. 'It's a bunch of nonsense,' he said, with nothing more to add.”
arizonadailystar-az.newsmemory.com?publink=33a9...
Reposted by Mark Marley
And the camera and the spacecraft were designed to be pointed at Mars 300 km below us, not out at an interstellar comet 30 million km away!
November 19, 2025 at 9:59 PM
And the camera and the spacecraft were designed to be pointed at Mars 300 km below us, not out at an interstellar comet 30 million km away!
Reposted by Mark Marley
Here’s an annotated version of our comet image.
We also want to thank our downlink and uplink teams who spent a huge amount of time working on this. Our camera was not designed to image interstellar objects 19 million miles away, but their hard work and planning paid off.
We also want to thank our downlink and uplink teams who spent a huge amount of time working on this. Our camera was not designed to image interstellar objects 19 million miles away, but their hard work and planning paid off.
November 19, 2025 at 9:31 PM
Here’s an annotated version of our comet image.
We also want to thank our downlink and uplink teams who spent a huge amount of time working on this. Our camera was not designed to image interstellar objects 19 million miles away, but their hard work and planning paid off.
We also want to thank our downlink and uplink teams who spent a huge amount of time working on this. Our camera was not designed to image interstellar objects 19 million miles away, but their hard work and planning paid off.
Lots of people thought of doing this, including me back on the day the comet was announced. Crazy fun to see the image now.
November 19, 2025 at 9:22 PM
Lots of people thought of doing this, including me back on the day the comet was announced. Crazy fun to see the image now.
Reposted by Mark Marley
Congratulations to the LPL's HiRISE team for successfully imaging interstellar comet 3I/ATLAS!
HiRISE Image of Exocomet 3I/ATLAS!
On 2 October 2025, MRO turned away from Mars to image 3I/ATLAS, only the third interstellar object ever observed passing through our solar system!
https://www.uahirise.org/releases/3i-atlas/
On 2 October 2025, MRO turned away from Mars to image 3I/ATLAS, only the third interstellar object ever observed passing through our solar system!
https://www.uahirise.org/releases/3i-atlas/
November 19, 2025 at 9:14 PM
Congratulations to the LPL's HiRISE team for successfully imaging interstellar comet 3I/ATLAS!
Amazing job by the HiRISE team @uahirise.bsky.social to target and image this object.
November 19, 2025 at 8:31 PM
Amazing job by the HiRISE team @uahirise.bsky.social to target and image this object.
Reposted by Mark Marley
NASA's pix of the interstellar comet 3I/ATLAS are now up science.nasa.gov/solar-system...
This is the HiRISE/MRO image ⬇️
This is the HiRISE/MRO image ⬇️
November 19, 2025 at 8:27 PM
NASA's pix of the interstellar comet 3I/ATLAS are now up science.nasa.gov/solar-system...
This is the HiRISE/MRO image ⬇️
This is the HiRISE/MRO image ⬇️
Reposted by Mark Marley
Our image should come online at uahirise.org very shortly.
HiRISE | High Resolution Imaging Science Experiment
uahirise.org
November 19, 2025 at 8:09 PM
Our image should come online at uahirise.org very shortly.
Reposted by Mark Marley
NASA Shares Interstellar Comet 3I/ATLAS Images
YouTube video by NASA
www.youtube.com
November 19, 2025 at 8:01 PM
Reposted by Mark Marley
🧪🔭⭐ #exoplanets #exoplanet #youngplanets
New paper from our group and @madysonbarber.bsky.social today!
We report a brand-new planet around a <50 Myr star—adding to a very small (but rapidly growing!) population of the youngest known transiting planets.
Paper: arxiv.org/pdf/2511.10734
New paper from our group and @madysonbarber.bsky.social today!
We report a brand-new planet around a <50 Myr star—adding to a very small (but rapidly growing!) population of the youngest known transiting planets.
Paper: arxiv.org/pdf/2511.10734
arxiv.org
November 19, 2025 at 2:43 PM
🧪🔭⭐ #exoplanets #exoplanet #youngplanets
New paper from our group and @madysonbarber.bsky.social today!
We report a brand-new planet around a <50 Myr star—adding to a very small (but rapidly growing!) population of the youngest known transiting planets.
Paper: arxiv.org/pdf/2511.10734
New paper from our group and @madysonbarber.bsky.social today!
We report a brand-new planet around a <50 Myr star—adding to a very small (but rapidly growing!) population of the youngest known transiting planets.
Paper: arxiv.org/pdf/2511.10734
A couple of weeks ago I started preparing today's Exoplanet grad class on atmospheric escape and thought, "why am I doing this when the world expert on atmospheric escape is Zahnle?". He kindly said yes to the ask, so I'm excited Kevin will be giving a remote lecture to my class today.
November 18, 2025 at 4:24 PM
A couple of weeks ago I started preparing today's Exoplanet grad class on atmospheric escape and thought, "why am I doing this when the world expert on atmospheric escape is Zahnle?". He kindly said yes to the ask, so I'm excited Kevin will be giving a remote lecture to my class today.
"Huge if True" podcast visited Mt. Lemmon and the Catalina Sky Survey @catalinaskysurvey.bsky.social
youtu.be/LOn-mmezykQ?...
youtu.be/LOn-mmezykQ?...
Humanity’s Real Plan to Stop This Asteroid (Feat. Mark Rober)
YouTube video by Cleo Abram
youtu.be
November 17, 2025 at 11:28 PM
"Huge if True" podcast visited Mt. Lemmon and the Catalina Sky Survey @catalinaskysurvey.bsky.social
youtu.be/LOn-mmezykQ?...
youtu.be/LOn-mmezykQ?...
We need a reimagined LPSC flavored meeting and the locale should be Tucson in March, after the gem show. Plenty of hotel choices along the free tram line that goes to the convention center. Visit Tucson is onboard to support this. If anyone has the bandwidth to invent the meeting we've got the city.
Abstracts submitted to LPSC 2026 are required to comply with White House (non-legally binding) executive orders forbidding mention of topics related to diversity, equity, and inclusion.
At least USRA/LPI isn't hiding it.
But is this what our community wants? Or deserves? I don't think so.
At least USRA/LPI isn't hiding it.
But is this what our community wants? Or deserves? I don't think so.
November 17, 2025 at 11:07 PM
We need a reimagined LPSC flavored meeting and the locale should be Tucson in March, after the gem show. Plenty of hotel choices along the free tram line that goes to the convention center. Visit Tucson is onboard to support this. If anyone has the bandwidth to invent the meeting we've got the city.
Great postdoc opportunity at LPL w/Sukrit Ranjan on exoplanet atmospheres including "hydrodynamic atmos. escape from rocky exoplanets, N & S cycling on early Mars & Earth, chem kinetics of early Earth, Venus, Mars...& interior-atmosphere interactions on rocky worlds" arizona.csod.com/ux/ats/caree...
Postdoctoral Research Associate I (Lunar and Planetary Laboratory)
The successful applicant will conduct original research in collaboration with Prof. Sukrit
Ranjan and his group related to the composition and structu...
arizona.csod.com
November 17, 2025 at 4:09 PM
Great postdoc opportunity at LPL w/Sukrit Ranjan on exoplanet atmospheres including "hydrodynamic atmos. escape from rocky exoplanets, N & S cycling on early Mars & Earth, chem kinetics of early Earth, Venus, Mars...& interior-atmosphere interactions on rocky worlds" arizona.csod.com/ux/ats/caree...