Mark Marley
@markmarley.bsky.social
Personal account. Substellar science since the 80s.
Had zero idea until just now about this different Daisy World.
November 16, 2025 at 6:28 PM
Had zero idea until just now about this different Daisy World.
More Tucson problems on the bike trail. Everyone, walkers included, was very chill and just went around behind the rattlesnake.
November 15, 2025 at 8:17 PM
More Tucson problems on the bike trail. Everyone, walkers included, was very chill and just went around behind the rattlesnake.
“I don’t need to bring the bins into the garage since they’ll be smart enough to smell that they are empty.”
November 15, 2025 at 5:56 PM
“I don’t need to bring the bins into the garage since they’ll be smart enough to smell that they are empty.”
The things you can find opening random storage closets in our basement.
November 14, 2025 at 9:19 PM
The things you can find opening random storage closets in our basement.
I'm co-author on a submitted paper that cited another group's modeling infrastructure and included their papers from 2001, 2004, 2006, 2009, 2011, 2013, 2017, and 2020. Reviewer: the actual paper from that group that lays out the model is 2008.
November 14, 2025 at 5:11 PM
I'm co-author on a submitted paper that cited another group's modeling infrastructure and included their papers from 2001, 2004, 2006, 2009, 2011, 2013, 2017, and 2020. Reviewer: the actual paper from that group that lays out the model is 2008.
Reposted by Mark Marley
Avi Loeb's calculations about 3I/ATLAS are 100% wrong because he has never understood that dust in the tail(s) responds to solar radiation pressure. Solar wind shapes the ion tail. But the radiation pressure is about 1000 times larger than the solar wind ram pressure, for particles that feel it.
November 13, 2025 at 9:36 PM
Avi Loeb's calculations about 3I/ATLAS are 100% wrong because he has never understood that dust in the tail(s) responds to solar radiation pressure. Solar wind shapes the ion tail. But the radiation pressure is about 1000 times larger than the solar wind ram pressure, for particles that feel it.
Former LPL Director Tim Swindle and me last night with former NASA astronaut Scott Altman who was CDR on the last two HST servicing missions. He told some hair raising stories about the two missions. Event was awarding of the Astronaut Scholarship Foundation recognition to a fantastic UA undergrad.
November 14, 2025 at 2:40 PM
Former LPL Director Tim Swindle and me last night with former NASA astronaut Scott Altman who was CDR on the last two HST servicing missions. He told some hair raising stories about the two missions. Event was awarding of the Astronaut Scholarship Foundation recognition to a fantastic UA undergrad.
Thanks so much to @luiswel.bsky.social who drove down twice from ASU to give two great lectures to my exoplanets grad class students. Explained both how retrievals work and how easy it can be to engineer the significance to tell the story you want. Plus a bonus visit by @joneskuma.bsky.social
November 14, 2025 at 2:21 PM
Thanks so much to @luiswel.bsky.social who drove down twice from ASU to give two great lectures to my exoplanets grad class students. Explained both how retrievals work and how easy it can be to engineer the significance to tell the story you want. Plus a bonus visit by @joneskuma.bsky.social
Reposted by Mark Marley
"The fallacies behind the cult of Loeb"
New entry in my blog. Other articles have covered the scientific aspects; this one reflects on the social phenomenon. I argue it’s driven by a series of fallacies
tinieblasyestrellas.blogspot.com/2025/11/the-...
New entry in my blog. Other articles have covered the scientific aspects; this one reflects on the social phenomenon. I argue it’s driven by a series of fallacies
tinieblasyestrellas.blogspot.com/2025/11/the-...
The fallacies behind the cult of Loeb
How media hype and misunderstanding fuel pseudoscientific fascination Introduction The word “cult” is used here in the sense given by...
tinieblasyestrellas.blogspot.com
November 13, 2025 at 11:09 AM
"The fallacies behind the cult of Loeb"
New entry in my blog. Other articles have covered the scientific aspects; this one reflects on the social phenomenon. I argue it’s driven by a series of fallacies
tinieblasyestrellas.blogspot.com/2025/11/the-...
New entry in my blog. Other articles have covered the scientific aspects; this one reflects on the social phenomenon. I argue it’s driven by a series of fallacies
tinieblasyestrellas.blogspot.com/2025/11/the-...
Big faculty shift in exoplanets. www.cbc.ca/news/science...
Quest to find another Earth brings renowned researcher home to Toronto | CBC News
Canadian astronomical research is getting a big boost with the return of Sara Seager to Canada after around 20 years at MIT. Her research includes looking for life in the clouds of Venus and searching...
www.cbc.ca
November 12, 2025 at 3:34 PM
Big faculty shift in exoplanets. www.cbc.ca/news/science...
Our local sky island aspens.
November 11, 2025 at 9:08 PM
Our local sky island aspens.
Reposted by Mark Marley
Flagstaff’s Lowell Observatory plans to cut nearly all its research funding and reduce the number of paid science staff to just two positions next year.
Lowell Observatory slashes research funding in the midst of financial struggle
Flagstaff’s Lowell Observatory plans to cut nearly all its research funding and reduce the number of paid science staff to just two positions next year.
buff.ly
November 10, 2025 at 7:00 PM
Flagstaff’s Lowell Observatory plans to cut nearly all its research funding and reduce the number of paid science staff to just two positions next year.
Reposted by Mark Marley
Why are planetary scientists, astrobiologists and and SETI scientists so negative (pissed off, even) about Avi Loeb’s repeated claims that 3I/Atlas may be an invading alien spaceship?
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(1/7)
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🧪🔭🛸
(1/7)
November 10, 2025 at 11:41 PM
Why are planetary scientists, astrobiologists and and SETI scientists so negative (pissed off, even) about Avi Loeb’s repeated claims that 3I/Atlas may be an invading alien spaceship?
🧵
🧪🔭🛸
(1/7)
🧵
🧪🔭🛸
(1/7)
This weekend I read that the entire Breaking Bad franchise is estimated to have had $385M in economic impact for the state of NM and this is celebrated by a statue at the ABQ convention center. Meanwhile University of Arizona space science has an economic impact of $560M on our state every year.
November 10, 2025 at 11:45 PM
This weekend I read that the entire Breaking Bad franchise is estimated to have had $385M in economic impact for the state of NM and this is celebrated by a statue at the ABQ convention center. Meanwhile University of Arizona space science has an economic impact of $560M on our state every year.
Reposted by Mark Marley
I've summarized the truth about Loeb's 10 "anomalies" about 3I/ATLAS in one post.
Thanks to @deschscoveries.bsky.social @michael-w-busch.bsky.social @cometary.org and @marshall-eubanks.bsky.social for contributing their expertise!
Thanks to @deschscoveries.bsky.social @michael-w-busch.bsky.social @cometary.org and @marshall-eubanks.bsky.social for contributing their expertise!
Loeb’s 3I/ATLAS “Anomalies” Explained
Avi Loeb continues to claim that 3I/ATLAS has many anomalous behaviors that lead to the conclusion that it “might” be an alien spacecraft. He carefully hedges the probability that it is a spacecraft ...
sites.psu.edu
November 10, 2025 at 12:22 AM
I've summarized the truth about Loeb's 10 "anomalies" about 3I/ATLAS in one post.
Thanks to @deschscoveries.bsky.social @michael-w-busch.bsky.social @cometary.org and @marshall-eubanks.bsky.social for contributing their expertise!
Thanks to @deschscoveries.bsky.social @michael-w-busch.bsky.social @cometary.org and @marshall-eubanks.bsky.social for contributing their expertise!
Reposted by Mark Marley
Picked up my 30th Potentially Hazardous Asteroid last shift. This one is interesting. In a retrograde comet-like orbit with a period around 26yrs but showing no activity at ~1 AU from the sun. Likely 1km + in size with Earth MOID = 0.0275 AU. Now published as 2025 VP.
November 9, 2025 at 12:24 AM
Picked up my 30th Potentially Hazardous Asteroid last shift. This one is interesting. In a retrograde comet-like orbit with a period around 26yrs but showing no activity at ~1 AU from the sun. Likely 1km + in size with Earth MOID = 0.0275 AU. Now published as 2025 VP.
Reposted by Mark Marley
Sharon was, to my great benefit, my boss, teacher, and mentor. And goddamn could she write. This lede!
A Sharon Begley byline, almost 5 years after her death.
Upon hearing the news James Watson had died, a STAT reporter said in our Slack, "I wish I could read what Sharon would have written."
Incredible news: Sharon in fact did pre-write a Watson obit. And it is masterful and excoriating.
🧪🧬🧫
Upon hearing the news James Watson had died, a STAT reporter said in our Slack, "I wish I could read what Sharon would have written."
Incredible news: Sharon in fact did pre-write a Watson obit. And it is masterful and excoriating.
🧪🧬🧫
James Watson, dead at 97, was a scientific legend and a pariah among his peers
James Watson, the co-discoverer of the structure of DNA who died Thursday at 97, was a scientific legend and a pariah among his peers.
www.statnews.com
November 8, 2025 at 11:33 PM
Sharon was, to my great benefit, my boss, teacher, and mentor. And goddamn could she write. This lede!
I don’t begrudge the hawk its dinner but wish it had eaten on the outside of the patio wall instead of inside.
November 8, 2025 at 11:14 PM
I don’t begrudge the hawk its dinner but wish it had eaten on the outside of the patio wall instead of inside.
Reposted by Mark Marley
We (The School of Earth and Space Exploration at ASU) are looking for a new director! Come be my new boss!
apply.interfolio.com/176991
apply.interfolio.com/176991
Apply - Interfolio
{{$ctrl.$state.data.pageTitle}} - Apply - Interfolio
apply.interfolio.com
November 8, 2025 at 10:18 PM
We (The School of Earth and Space Exploration at ASU) are looking for a new director! Come be my new boss!
apply.interfolio.com/176991
apply.interfolio.com/176991
Goddard is a critical component of the US capability to study Earth, the sun, the solar system, and our universe. Discarding pieces of this capability without a great deal of forethought is a major mistake.
🚨 NASA scientists warn: critical equipment at Goddard Space Flight Center could be discarded during the shutdown, jeopardizing decades of Earth & space science missions.
📢 Act now: agu.quorum.us/campaign/146...
#sciencepolicy #saveNASA
📢 Act now: agu.quorum.us/campaign/146...
#sciencepolicy #saveNASA
November 7, 2025 at 2:35 PM
Goddard is a critical component of the US capability to study Earth, the sun, the solar system, and our universe. Discarding pieces of this capability without a great deal of forethought is a major mistake.
Q&A with @catalinaskysurvey.bsky.social's Director Carson Fuls about discovering Comet Lemmon. news.arizona.edu/employee-new...
Q&A: Look up! What it takes to discover a comet
Comet "Lemmon" was discovered by the University of Arizona's Catalina Sky Survey. CSS Director Carson Fuls sat in the observing room on a cold winter night when the comet first announced itself as a f...
news.arizona.edu
November 6, 2025 at 3:01 PM
Q&A with @catalinaskysurvey.bsky.social's Director Carson Fuls about discovering Comet Lemmon. news.arizona.edu/employee-new...
Today Show Tucson feature this morning ideally should have had featured the other side of Cherry in this aerial shot.
November 6, 2025 at 1:51 AM
Today Show Tucson feature this morning ideally should have had featured the other side of Cherry in this aerial shot.
Reposted by Mark Marley
Enjoyed giving a UofA Origins talk on how protoplanetary disks evolve – featuring new results from ALMA and JWST. The recording is available here 👇
youtu.be/mdgGgnjVbb0
@uarizonalpl.bsky.social @stewardobservatory.bsky.social
youtu.be/mdgGgnjVbb0
@uarizonalpl.bsky.social @stewardobservatory.bsky.social
Protoplanetary Disk Evolution in the ALMA–JWST Era (Ilaria Pascucci, UArizona/LPL)
YouTube video by Origins Seminars
youtu.be
November 5, 2025 at 4:10 PM
Enjoyed giving a UofA Origins talk on how protoplanetary disks evolve – featuring new results from ALMA and JWST. The recording is available here 👇
youtu.be/mdgGgnjVbb0
@uarizonalpl.bsky.social @stewardobservatory.bsky.social
youtu.be/mdgGgnjVbb0
@uarizonalpl.bsky.social @stewardobservatory.bsky.social
Reposted by Mark Marley
November 3, 2025 at 1:14 PM