astrafoxen
@astrafoxen.bsky.social
20 - any pronouns
Astrophysics undergrad student in California (grad '27), aspiring planetary scientist. I do astronomy research on asteroids, comets and TNOs!
pfp by EchaSkqech
banner by Ian Regan
Astrophysics undergrad student in California (grad '27), aspiring planetary scientist. I do astronomy research on asteroids, comets and TNOs!
pfp by EchaSkqech
banner by Ian Regan
Some stuff I did for the first 3 days of @morgandenman.bsky.social's #SpacetoberChallenge! Been too busy with college so I can't do these on time blehhhh
(I'll post these individually later)
(I'll post these individually later)
October 6, 2025 at 8:21 PM
Some stuff I did for the first 3 days of @morgandenman.bsky.social's #SpacetoberChallenge! Been too busy with college so I can't do these on time blehhhh
(I'll post these individually later)
(I'll post these individually later)
The IAU announced official names for Donaldjohanson's surface & shape features 2 weeks ago, but nobody has mentioned the news. They're all named after archeological sites and hominin fossils, which is fun and awesome haha
(Afar Lobus = small lobe, Olduvai Lobus = big lobe, Windover Collum = neck)
(Afar Lobus = small lobe, Olduvai Lobus = big lobe, Windover Collum = neck)
September 9, 2025 at 7:11 AM
The IAU announced official names for Donaldjohanson's surface & shape features 2 weeks ago, but nobody has mentioned the news. They're all named after archeological sites and hominin fossils, which is fun and awesome haha
(Afar Lobus = small lobe, Olduvai Lobus = big lobe, Windover Collum = neck)
(Afar Lobus = small lobe, Olduvai Lobus = big lobe, Windover Collum = neck)
MORE DWARF PLANETS AND BIG TNOS NAMED BY THE IAU TODAY YEAHHHHH
2004 GV9 → Goibniu
2005 RM43 → Rumina
2002 UX25 & moon → Uni & Tinia
* Uni is weird because it's made of holey ice less dense than water
2002 XW93 → Xewioso
2013 FY27 → Chiminigagua (named 3 weeks ago, but nobody mentioned it on bsky)
2004 GV9 → Goibniu
2005 RM43 → Rumina
2002 UX25 & moon → Uni & Tinia
* Uni is weird because it's made of holey ice less dense than water
2002 XW93 → Xewioso
2013 FY27 → Chiminigagua (named 3 weeks ago, but nobody mentioned it on bsky)
September 1, 2025 at 6:22 PM
MORE DWARF PLANETS AND BIG TNOS NAMED BY THE IAU TODAY YEAHHHHH
2004 GV9 → Goibniu
2005 RM43 → Rumina
2002 UX25 & moon → Uni & Tinia
* Uni is weird because it's made of holey ice less dense than water
2002 XW93 → Xewioso
2013 FY27 → Chiminigagua (named 3 weeks ago, but nobody mentioned it on bsky)
2004 GV9 → Goibniu
2005 RM43 → Rumina
2002 UX25 & moon → Uni & Tinia
* Uni is weird because it's made of holey ice less dense than water
2002 XW93 → Xewioso
2013 FY27 → Chiminigagua (named 3 weeks ago, but nobody mentioned it on bsky)
weyWHAT
An unexpected occultation discovery of a potential 2nd moon or 3rd ring arc around dwarf planet Quaoar!
The new moon/ring is 30±2 km wide and seems to be 5757 km from Quaoar—suspiciously close to 7:2 orbital resonance with Quaoar's big moon Weywot!
iopscience.iop.org/article/10.3... ☄️
An unexpected occultation discovery of a potential 2nd moon or 3rd ring arc around dwarf planet Quaoar!
The new moon/ring is 30±2 km wide and seems to be 5757 km from Quaoar—suspiciously close to 7:2 orbital resonance with Quaoar's big moon Weywot!
iopscience.iop.org/article/10.3... ☄️
August 29, 2025 at 12:07 AM
weyWHAT
An unexpected occultation discovery of a potential 2nd moon or 3rd ring arc around dwarf planet Quaoar!
The new moon/ring is 30±2 km wide and seems to be 5757 km from Quaoar—suspiciously close to 7:2 orbital resonance with Quaoar's big moon Weywot!
iopscience.iop.org/article/10.3... ☄️
An unexpected occultation discovery of a potential 2nd moon or 3rd ring arc around dwarf planet Quaoar!
The new moon/ring is 30±2 km wide and seems to be 5757 km from Quaoar—suspiciously close to 7:2 orbital resonance with Quaoar's big moon Weywot!
iopscience.iop.org/article/10.3... ☄️
Yeah, that checks out. This is what I get when I do pixel mapping (image derotated this time):
August 28, 2025 at 6:44 AM
Yeah, that checks out. This is what I get when I do pixel mapping (image derotated this time):
Hm, to me I'm 100% sure there's an elongation. The angular separation is 30-40 milliarcseconds, which is consistent with reported values for Lempo-Hiisi. The PSF of Lempo-Hiisi doesn't look the same as Paha.
I have no clue which of the upper/lower components is Lempo or Hiisi however.
I have no clue which of the upper/lower components is Lempo or Hiisi however.
August 28, 2025 at 6:37 AM
Hm, to me I'm 100% sure there's an elongation. The angular separation is 30-40 milliarcseconds, which is consistent with reported values for Lempo-Hiisi. The PSF of Lempo-Hiisi doesn't look the same as Paha.
I have no clue which of the upper/lower components is Lempo or Hiisi however.
I have no clue which of the upper/lower components is Lempo or Hiisi however.
Here's the full paper btw zenodo.org/records/1694...
Absolutely gorgeous spectrum (left image) showing the crapton of CO2 in this comet.
And apparently 3I/ATLAS may have the third highest CO2 abundance relative to water seen in a comet!
Absolutely gorgeous spectrum (left image) showing the crapton of CO2 in this comet.
And apparently 3I/ATLAS may have the third highest CO2 abundance relative to water seen in a comet!
August 25, 2025 at 10:27 PM
Here's the full paper btw zenodo.org/records/1694...
Absolutely gorgeous spectrum (left image) showing the crapton of CO2 in this comet.
And apparently 3I/ATLAS may have the third highest CO2 abundance relative to water seen in a comet!
Absolutely gorgeous spectrum (left image) showing the crapton of CO2 in this comet.
And apparently 3I/ATLAS may have the third highest CO2 abundance relative to water seen in a comet!
jamming to deltarune song remixes while fighting space misinformation :3
(I've been busy improving the 3I/ATLAS Wikipedia article..!)
en.wikipedia.org/wiki/3I/ATLAS
(I've been busy improving the 3I/ATLAS Wikipedia article..!)
en.wikipedia.org/wiki/3I/ATLAS
July 30, 2025 at 8:03 PM
jamming to deltarune song remixes while fighting space misinformation :3
(I've been busy improving the 3I/ATLAS Wikipedia article..!)
en.wikipedia.org/wiki/3I/ATLAS
(I've been busy improving the 3I/ATLAS Wikipedia article..!)
en.wikipedia.org/wiki/3I/ATLAS
(no worries, questions appreciated!)
3I was moving at a rate of 1.56 arcsec/minute in the sky, which translates to 39 pixels per minute in Hubble's Wide-Field Camera (aka "WFC3"). Hubble's WFC3 has a FOV of 160x160 arcsec, or 4000x4000 pixels; I had to crop out a lot. Full image looks like this:
3I was moving at a rate of 1.56 arcsec/minute in the sky, which translates to 39 pixels per minute in Hubble's Wide-Field Camera (aka "WFC3"). Hubble's WFC3 has a FOV of 160x160 arcsec, or 4000x4000 pixels; I had to crop out a lot. Full image looks like this:
July 22, 2025 at 7:52 PM
(no worries, questions appreciated!)
3I was moving at a rate of 1.56 arcsec/minute in the sky, which translates to 39 pixels per minute in Hubble's Wide-Field Camera (aka "WFC3"). Hubble's WFC3 has a FOV of 160x160 arcsec, or 4000x4000 pixels; I had to crop out a lot. Full image looks like this:
3I was moving at a rate of 1.56 arcsec/minute in the sky, which translates to 39 pixels per minute in Hubble's Wide-Field Camera (aka "WFC3"). Hubble's WFC3 has a FOV of 160x160 arcsec, or 4000x4000 pixels; I had to crop out a lot. Full image looks like this:
Quick aside, I'm really happy that more big TNOs/dwarf planet candidates got official names this year, 2 decades after their discovery :D
2005 RN43 → "Ritona" today
2003 AZ84 → "Achlys" on June 30
2002 AW197 → "Aya" on June 30
2002 MS4 → "Máni" on June 9
(size comparison by Lunathesilly on wiki)
2005 RN43 → "Ritona" today
2003 AZ84 → "Achlys" on June 30
2002 AW197 → "Aya" on June 30
2002 MS4 → "Máni" on June 9
(size comparison by Lunathesilly on wiki)
July 22, 2025 at 3:30 AM
Quick aside, I'm really happy that more big TNOs/dwarf planet candidates got official names this year, 2 decades after their discovery :D
2005 RN43 → "Ritona" today
2003 AZ84 → "Achlys" on June 30
2002 AW197 → "Aya" on June 30
2002 MS4 → "Máni" on June 9
(size comparison by Lunathesilly on wiki)
2005 RN43 → "Ritona" today
2003 AZ84 → "Achlys" on June 30
2002 AW197 → "Aya" on June 30
2002 MS4 → "Máni" on June 9
(size comparison by Lunathesilly on wiki)
And here is a 4-frame median stack of the 16 and 18 UTC image pairs:
July 22, 2025 at 12:34 AM
And here is a 4-frame median stack of the 16 and 18 UTC image pairs:
Two hours later (Jul 21, 18:05 UTC), Hubble took some more images of 3I/ATLAS!
BTW, you can download and see the calibrated (DRZ) Hubble images yourself at mast.stsci.edu/search/ui/#/.... You'll need a program that can open FITS-format images (like Aladin, FITSviewer, etc. Go wild with em)
BTW, you can download and see the calibrated (DRZ) Hubble images yourself at mast.stsci.edu/search/ui/#/.... You'll need a program that can open FITS-format images (like Aladin, FITSviewer, etc. Go wild with em)
July 22, 2025 at 12:24 AM
Two hours later (Jul 21, 18:05 UTC), Hubble took some more images of 3I/ATLAS!
BTW, you can download and see the calibrated (DRZ) Hubble images yourself at mast.stsci.edu/search/ui/#/.... You'll need a program that can open FITS-format images (like Aladin, FITSviewer, etc. Go wild with em)
BTW, you can download and see the calibrated (DRZ) Hubble images yourself at mast.stsci.edu/search/ui/#/.... You'll need a program that can open FITS-format images (like Aladin, FITSviewer, etc. Go wild with em)
Yep! Right now the tail is being viewed at a head-on perspective from Earth (& Hubble), so the tail's behind the nucleus and is foreshortened (said in arxiv.org/pdf/2507.05226). Sorta like looking directly down at the tip of a cone. The tail looks like it's pointed toward the Sun, but it's geometry.
July 22, 2025 at 12:11 AM
Yep! Right now the tail is being viewed at a head-on perspective from Earth (& Hubble), so the tail's behind the nucleus and is foreshortened (said in arxiv.org/pdf/2507.05226). Sorta like looking directly down at the tip of a cone. The tail looks like it's pointed toward the Sun, but it's geometry.
I'm not sure which right hand corner you're talking about. But if you're talking about those small white specks with upper-right-pointing tails, those are cosmic rays. 3I/ATLAS's tail looks stubby and diffuse, from what I can tell from playing around with the contrast.
July 21, 2025 at 9:47 PM
I'm not sure which right hand corner you're talking about. But if you're talking about those small white specks with upper-right-pointing tails, those are cosmic rays. 3I/ATLAS's tail looks stubby and diffuse, from what I can tell from playing around with the contrast.
And a couple more processings I did with the calibrated Hubble images:
July 21, 2025 at 9:28 PM
And a couple more processings I did with the calibrated Hubble images:
Hubble Space Telescope images of interstellar comet 3I/ATLAS are out! These were taken 5 hours ago. Plenty of cosmic rays peppering the images, but the comet's coma looks very nice and puffy. Best of luck to the researchers trying to write up papers for this... archive.stsci.edu/proposal_sea... 🔭
July 21, 2025 at 9:28 PM
Hubble Space Telescope images of interstellar comet 3I/ATLAS are out! These were taken 5 hours ago. Plenty of cosmic rays peppering the images, but the comet's coma looks very nice and puffy. Best of luck to the researchers trying to write up papers for this... archive.stsci.edu/proposal_sea... 🔭
OH MY GOD
NEW HUBBLE CYCLE 33 PROPOSALS ARE OUT AND THERE'S SO MANY UPCOMING TNO OBSERVATIONS
NEW HUBBLE CYCLE 33 PROPOSALS ARE OUT AND THERE'S SO MANY UPCOMING TNO OBSERVATIONS
July 21, 2025 at 7:38 PM
OH MY GOD
NEW HUBBLE CYCLE 33 PROPOSALS ARE OUT AND THERE'S SO MANY UPCOMING TNO OBSERVATIONS
NEW HUBBLE CYCLE 33 PROPOSALS ARE OUT AND THERE'S SO MANY UPCOMING TNO OBSERVATIONS
Olivier Hainaut & others got some really nice images of 3I/ATLAS's fuzzy coma with the Very Large Telescope last night! The images are already public on the ESO science archive. archive.eso.org/downloadport...
July 4, 2025 at 9:42 PM
Olivier Hainaut & others got some really nice images of 3I/ATLAS's fuzzy coma with the Very Large Telescope last night! The images are already public on the ESO science archive. archive.eso.org/downloadport...
New paper on interstellar comet #3I/ATLAS is out on arXiv! By Darryl Seligman and more.
Images show a fuzzy tail, and the comet's dusty coma is similarly reddish like the other interstellar comet 2I/Borisov.
arxiv.org/abs/2507.02757
☄️🔭🧪
Images show a fuzzy tail, and the comet's dusty coma is similarly reddish like the other interstellar comet 2I/Borisov.
arxiv.org/abs/2507.02757
☄️🔭🧪
July 4, 2025 at 1:32 AM
New paper on interstellar comet #3I/ATLAS is out on arXiv! By Darryl Seligman and more.
Images show a fuzzy tail, and the comet's dusty coma is similarly reddish like the other interstellar comet 2I/Borisov.
arxiv.org/abs/2507.02757
☄️🔭🧪
Images show a fuzzy tail, and the comet's dusty coma is similarly reddish like the other interstellar comet 2I/Borisov.
arxiv.org/abs/2507.02757
☄️🔭🧪
UPDATE ON INTERSTELLAR COMET #A11pl3Z:
It's OFFICIALLY LABELED 3I/ATLAS by the Minor Planet Center!!! minorplanetcenter.net/mpec/K25/K25...
HUGE thank you to all the astronomers for confirming this object! The next step now is someone getting the big scopes (Hubble, JWST, etc.) to look at it!
☄️🔭🧪
It's OFFICIALLY LABELED 3I/ATLAS by the Minor Planet Center!!! minorplanetcenter.net/mpec/K25/K25...
HUGE thank you to all the astronomers for confirming this object! The next step now is someone getting the big scopes (Hubble, JWST, etc.) to look at it!
☄️🔭🧪
July 2, 2025 at 9:46 PM
UPDATE ON INTERSTELLAR COMET #A11pl3Z:
It's OFFICIALLY LABELED 3I/ATLAS by the Minor Planet Center!!! minorplanetcenter.net/mpec/K25/K25...
HUGE thank you to all the astronomers for confirming this object! The next step now is someone getting the big scopes (Hubble, JWST, etc.) to look at it!
☄️🔭🧪
It's OFFICIALLY LABELED 3I/ATLAS by the Minor Planet Center!!! minorplanetcenter.net/mpec/K25/K25...
HUGE thank you to all the astronomers for confirming this object! The next step now is someone getting the big scopes (Hubble, JWST, etc.) to look at it!
☄️🔭🧪
ANOTHER UPDATE on interstellar object #A11pl3Z:
Even MORE early obs from June 14-21 were found from the Zwicky Transient Facility!
Now with 18 days of data, we have a lower eccentricity of e=6.11±0.14 for A11pl3Z's hyperbolic trajectory.
(Sam Deen also notes ATLAS obs from Jun 4-17, unsubmitted)
🔭☄️
Even MORE early obs from June 14-21 were found from the Zwicky Transient Facility!
Now with 18 days of data, we have a lower eccentricity of e=6.11±0.14 for A11pl3Z's hyperbolic trajectory.
(Sam Deen also notes ATLAS obs from Jun 4-17, unsubmitted)
🔭☄️
July 2, 2025 at 4:54 AM
ANOTHER UPDATE on interstellar object #A11pl3Z:
Even MORE early obs from June 14-21 were found from the Zwicky Transient Facility!
Now with 18 days of data, we have a lower eccentricity of e=6.11±0.14 for A11pl3Z's hyperbolic trajectory.
(Sam Deen also notes ATLAS obs from Jun 4-17, unsubmitted)
🔭☄️
Even MORE early obs from June 14-21 were found from the Zwicky Transient Facility!
Now with 18 days of data, we have a lower eccentricity of e=6.11±0.14 for A11pl3Z's hyperbolic trajectory.
(Sam Deen also notes ATLAS obs from Jun 4-17, unsubmitted)
🔭☄️
Yeah, that's what I thought too. The first frame definitely has some diffuse haze, whereas the remaining frames are slightly affected by weather and hard to tell. I tried a 5x600s median and additive stack, but still not sure what to think of it.
July 2, 2025 at 3:35 AM
Yeah, that's what I thought too. The first frame definitely has some diffuse haze, whereas the remaining frames are slightly affected by weather and hard to tell. I tried a 5x600s median and additive stack, but still not sure what to think of it.
Another update on interstellar object #A11pl3Z:
Even earlier observations from June 24 were found from the ATLAS telescope. Now with 7 days' worth of data, the eccentricity of A11pl3Z's trajectory is updated to e=9.9±0.9.
🔭☄️
Even earlier observations from June 24 were found from the ATLAS telescope. Now with 7 days' worth of data, the eccentricity of A11pl3Z's trajectory is updated to e=9.9±0.9.
🔭☄️
July 2, 2025 at 3:20 AM
Another update on interstellar object #A11pl3Z:
Even earlier observations from June 24 were found from the ATLAS telescope. Now with 7 days' worth of data, the eccentricity of A11pl3Z's trajectory is updated to e=9.9±0.9.
🔭☄️
Even earlier observations from June 24 were found from the ATLAS telescope. Now with 7 days' worth of data, the eccentricity of A11pl3Z's trajectory is updated to e=9.9±0.9.
🔭☄️
Here's our images of interstellar object #A11pl3Z from Deep Random Survey's 0.43-meter scope @ Chile. The telescope was following A11pl3Z's motion, so stars appear smeared. Weather got worse by the end, so still hard to tell if it's a comet.
600-sec exposures, from 2025 Jul 2, 00:42-01:23 UT
🔭☄️
600-sec exposures, from 2025 Jul 2, 00:42-01:23 UT
🔭☄️
July 2, 2025 at 3:07 AM
Here's our images of interstellar object #A11pl3Z from Deep Random Survey's 0.43-meter scope @ Chile. The telescope was following A11pl3Z's motion, so stars appear smeared. Weather got worse by the end, so still hard to tell if it's a comet.
600-sec exposures, from 2025 Jul 2, 00:42-01:23 UT
🔭☄️
600-sec exposures, from 2025 Jul 2, 00:42-01:23 UT
🔭☄️
UPDATE on our new interstellar friend #A11pl3Z:
Citizen scientist Sam Deen has found earlier observations of from June 25-28, from the ATLAS telescope!
Now with 6 days' worth of data, the eccentricity of A11pl3Z's trajectory is narrowed down to e=10.4 ± 1.1!
... that's undoubtedly interstellar.
🔭☄️
Citizen scientist Sam Deen has found earlier observations of from June 25-28, from the ATLAS telescope!
Now with 6 days' worth of data, the eccentricity of A11pl3Z's trajectory is narrowed down to e=10.4 ± 1.1!
... that's undoubtedly interstellar.
🔭☄️
July 2, 2025 at 2:37 AM
UPDATE on our new interstellar friend #A11pl3Z:
Citizen scientist Sam Deen has found earlier observations of from June 25-28, from the ATLAS telescope!
Now with 6 days' worth of data, the eccentricity of A11pl3Z's trajectory is narrowed down to e=10.4 ± 1.1!
... that's undoubtedly interstellar.
🔭☄️
Citizen scientist Sam Deen has found earlier observations of from June 25-28, from the ATLAS telescope!
Now with 6 days' worth of data, the eccentricity of A11pl3Z's trajectory is narrowed down to e=10.4 ± 1.1!
... that's undoubtedly interstellar.
🔭☄️