Gijs D Mulders
@gijsmulders.com
Pinned
Reposted by Gijs D Mulders
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 Gijs D Mulders
Big congrats to Jennifer Burt, Xavier Dumusque, and Sam Halverson on finishing their epic (instant classic) Annual Reviews of Astronomy & Astrophysics article "Precise Radial Velocities"!
arxiv.org/abs/2511.01954
contains some great new graphics for talks on
#exoplanets #EPRV #DopplerSpectroscopy
arxiv.org/abs/2511.01954
contains some great new graphics for talks on
#exoplanets #EPRV #DopplerSpectroscopy
November 5, 2025 at 7:20 AM
Big congrats to Jennifer Burt, Xavier Dumusque, and Sam Halverson on finishing their epic (instant classic) Annual Reviews of Astronomy & Astrophysics article "Precise Radial Velocities"!
arxiv.org/abs/2511.01954
contains some great new graphics for talks on
#exoplanets #EPRV #DopplerSpectroscopy
arxiv.org/abs/2511.01954
contains some great new graphics for talks on
#exoplanets #EPRV #DopplerSpectroscopy
Reposted by Gijs D Mulders
The NASA #Exoplanet Archive now has Gaia DR3 IDs! This should hopefully make your work and planning observations easier!
exoplanetarchive.ipac.caltech.edu
exoplanetarchive.ipac.caltech.edu
October 16, 2025 at 10:47 PM
The NASA #Exoplanet Archive now has Gaia DR3 IDs! This should hopefully make your work and planning observations easier!
exoplanetarchive.ipac.caltech.edu
exoplanetarchive.ipac.caltech.edu
Reposted by Gijs D Mulders
w/ Oli Shorttle, @johannateske.bsky.social & Eliza Kempton we reviewed our current understanding and prospects for peaking on the inside of small #exoplanets in "Constraining exoplanet interiors using observations of their atmospheres": www.science.org/stoken/autho... & arxiv.org/abs/2510.08844 🔭🧪⚒️☄️
October 13, 2025 at 12:27 PM
w/ Oli Shorttle, @johannateske.bsky.social & Eliza Kempton we reviewed our current understanding and prospects for peaking on the inside of small #exoplanets in "Constraining exoplanet interiors using observations of their atmospheres": www.science.org/stoken/autho... & arxiv.org/abs/2510.08844 🔭🧪⚒️☄️
October 8, 2025 at 9:10 PM
Reposted by Gijs D Mulders
Our paper on the JWST/MIRI observations of the epsilon Eridani system, led by Dr. Schuyler Wolff, were published today! This is the last of the Archetypical Disks in our MIRI Survey, after Fomalhaut and Vega. Just like for those disks, our MIRI images reveal an extended inner asteroid disk!
September 29, 2025 at 7:35 PM
Our paper on the JWST/MIRI observations of the epsilon Eridani system, led by Dr. Schuyler Wolff, were published today! This is the last of the Archetypical Disks in our MIRI Survey, after Fomalhaut and Vega. Just like for those disks, our MIRI images reveal an extended inner asteroid disk!
Reposted by Gijs D Mulders
I'm really excited about this one! It's fantastic working with Dr. Yayaati Chachan:
arxiv.org/abs/2509.20428
"Revising the Giant Planet Mass-Metallicity Relation: Deciphering the Formation Sequence of Giant Planets"
Lots of great nuggets her, including that even super-Jupiters are very metal-rich.
arxiv.org/abs/2509.20428
"Revising the Giant Planet Mass-Metallicity Relation: Deciphering the Formation Sequence of Giant Planets"
Lots of great nuggets her, including that even super-Jupiters are very metal-rich.
Revising the Giant Planet Mass-Metallicity Relation: Deciphering the Formation Sequence of Giant Planets
The rate at which giant planets accumulate solids and gas is a critical component of planet formation models, yet it is extremely challenging to predict from first principles. Characterizing the heavy...
arxiv.org
September 26, 2025 at 4:25 AM
I'm really excited about this one! It's fantastic working with Dr. Yayaati Chachan:
arxiv.org/abs/2509.20428
"Revising the Giant Planet Mass-Metallicity Relation: Deciphering the Formation Sequence of Giant Planets"
Lots of great nuggets her, including that even super-Jupiters are very metal-rich.
arxiv.org/abs/2509.20428
"Revising the Giant Planet Mass-Metallicity Relation: Deciphering the Formation Sequence of Giant Planets"
Lots of great nuggets her, including that even super-Jupiters are very metal-rich.
Reposted by Gijs D Mulders
Sometimes 2025 just feels like a lot, and you need an excuse to celebrate your fabulous team (and the whole exoplanet community!) reaching a new milestone…
Happy 6,000 Confirmed Exoplanets Day, everybody!!!!
(You may recognize the narrator of the video at the link! 🫣)
www.nasa.gov/universe/exo...
Happy 6,000 Confirmed Exoplanets Day, everybody!!!!
(You may recognize the narrator of the video at the link! 🫣)
www.nasa.gov/universe/exo...
September 17, 2025 at 6:22 PM
Sometimes 2025 just feels like a lot, and you need an excuse to celebrate your fabulous team (and the whole exoplanet community!) reaching a new milestone…
Happy 6,000 Confirmed Exoplanets Day, everybody!!!!
(You may recognize the narrator of the video at the link! 🫣)
www.nasa.gov/universe/exo...
Happy 6,000 Confirmed Exoplanets Day, everybody!!!!
(You may recognize the narrator of the video at the link! 🫣)
www.nasa.gov/universe/exo...
Reposted by Gijs D Mulders
Paper day!
You're doing ground-based high-resolution exoplanet transmission spectroscopy and want to analyse the planet—not the star or Earth's atmosphere.
Is there a way to disentangle your spectrum *without* destroying the planet signal?
arxiv.org/abs/2509.12737
🧵⬇️
🔭 #exoplanets #astromethods
You're doing ground-based high-resolution exoplanet transmission spectroscopy and want to analyse the planet—not the star or Earth's atmosphere.
Is there a way to disentangle your spectrum *without* destroying the planet signal?
arxiv.org/abs/2509.12737
🧵⬇️
🔭 #exoplanets #astromethods
TSD: An inverse problem approach for recovering the exoplanetary atmosphere transmission spectrum from high-resolution spectroscopy
Our ability to observe, detect, and characterize exoplanetary atmospheres has grown by leaps and bounds over the last 20 years, aided largely by developments in astronomical instrumentation; improveme...
arxiv.org
September 17, 2025 at 3:05 PM
Paper day!
You're doing ground-based high-resolution exoplanet transmission spectroscopy and want to analyse the planet—not the star or Earth's atmosphere.
Is there a way to disentangle your spectrum *without* destroying the planet signal?
arxiv.org/abs/2509.12737
🧵⬇️
🔭 #exoplanets #astromethods
You're doing ground-based high-resolution exoplanet transmission spectroscopy and want to analyse the planet—not the star or Earth's atmosphere.
Is there a way to disentangle your spectrum *without* destroying the planet signal?
arxiv.org/abs/2509.12737
🧵⬇️
🔭 #exoplanets #astromethods
Reposted by Gijs D Mulders
For the last two years, I've been paying for the Astronomy feeds hosting myself.
It has been a privilege to grow our community here, but I also shouldn't keep doing it for free 😅
That's why I'm delighted to announce that we now have a donations page on Open Collective! 🔭☄️ #astrophotography
It has been a privilege to grow our community here, but I also shouldn't keep doing it for free 😅
That's why I'm delighted to announce that we now have a donations page on Open Collective! 🔭☄️ #astrophotography
The Astrosky Ecosystem - Open Collective
We're building an open-source ecosystem of social media tools for the space science & astronomy communities.
opencollective.com
September 8, 2025 at 3:51 PM
For the last two years, I've been paying for the Astronomy feeds hosting myself.
It has been a privilege to grow our community here, but I also shouldn't keep doing it for free 😅
That's why I'm delighted to announce that we now have a donations page on Open Collective! 🔭☄️ #astrophotography
It has been a privilege to grow our community here, but I also shouldn't keep doing it for free 😅
That's why I'm delighted to announce that we now have a donations page on Open Collective! 🔭☄️ #astrophotography
Reposted by Gijs D Mulders
Seems like Ayumu Shoshi et al. did take a high-resolution ALMA image of the disk around IRAS 04125+2902. arxiv.org/abs/2509.01896
This system also has the youngest transiting #exoplanet, discovered in November 2024 with TESS.
Disk, planet orbit and outer stellar companion orbit are all misaligned.
This system also has the youngest transiting #exoplanet, discovered in November 2024 with TESS.
Disk, planet orbit and outer stellar companion orbit are all misaligned.
September 3, 2025 at 8:21 AM
Seems like Ayumu Shoshi et al. did take a high-resolution ALMA image of the disk around IRAS 04125+2902. arxiv.org/abs/2509.01896
This system also has the youngest transiting #exoplanet, discovered in November 2024 with TESS.
Disk, planet orbit and outer stellar companion orbit are all misaligned.
This system also has the youngest transiting #exoplanet, discovered in November 2024 with TESS.
Disk, planet orbit and outer stellar companion orbit are all misaligned.
Reposted by Gijs D Mulders
Proud supervisor moment: #LeidenObservatory graduate student Richelle van Capelleveen led one of two papers on our discovery of WISPIT 2b, a 5 Jupiter mass exoplanet clearing a path in a circumstellar disk. Laird Close and his team saw it in H-alpha, indicating gas accretion #astrodon 🔭 🧪
August 26, 2025 at 11:51 AM
Proud supervisor moment: #LeidenObservatory graduate student Richelle van Capelleveen led one of two papers on our discovery of WISPIT 2b, a 5 Jupiter mass exoplanet clearing a path in a circumstellar disk. Laird Close and his team saw it in H-alpha, indicating gas accretion #astrodon 🔭 🧪
Reposted by Gijs D Mulders
New protoplanet(s?) alert! I'm happy to share this LBTI image of WISPIT 2 from our team's paper led by Laird Close. Planet b was discovered at Hα with MagAO-X following the SPHERE disk discovery (R. van Capelleveen +), and CC1 might be a candidate 2nd (enshrouded?) protoplanet #exoplanets ☄️🔭🧪
August 26, 2025 at 5:40 PM
New protoplanet(s?) alert! I'm happy to share this LBTI image of WISPIT 2 from our team's paper led by Laird Close. Planet b was discovered at Hα with MagAO-X following the SPHERE disk discovery (R. van Capelleveen +), and CC1 might be a candidate 2nd (enshrouded?) protoplanet #exoplanets ☄️🔭🧪
August 20, 2025 at 10:04 PM
Reposted by Gijs D Mulders
I think that mass-loss is important for sub-Neptunes and the "radius valley," but I do not think that "core-powered" escape is significant. We find that "Boil-off," right when the disk dissipates, and then XUV driven escape, are major influences.
ui.adsabs.harvard.edu/abs/2024ApJ....
ui.adsabs.harvard.edu/abs/2024ApJ....
ui.adsabs.harvard.edu
August 19, 2025 at 7:06 PM
I think that mass-loss is important for sub-Neptunes and the "radius valley," but I do not think that "core-powered" escape is significant. We find that "Boil-off," right when the disk dissipates, and then XUV driven escape, are major influences.
ui.adsabs.harvard.edu/abs/2024ApJ....
ui.adsabs.harvard.edu/abs/2024ApJ....
Question for the radial velocity #exoplanets experts:
Is there an animation that shows two spectra being shifted with respect to each other and the corresponding values of the cross correlation function changing?
I think I’ve seen one in a talk but can’t find a nice animation online
Is there an animation that shows two spectra being shifted with respect to each other and the corresponding values of the cross correlation function changing?
I think I’ve seen one in a talk but can’t find a nice animation online
August 18, 2025 at 11:19 PM
Question for the radial velocity #exoplanets experts:
Is there an animation that shows two spectra being shifted with respect to each other and the corresponding values of the cross correlation function changing?
I think I’ve seen one in a talk but can’t find a nice animation online
Is there an animation that shows two spectra being shifted with respect to each other and the corresponding values of the cross correlation function changing?
I think I’ve seen one in a talk but can’t find a nice animation online
Reposted by Gijs D Mulders
We looked for an atmosphere on TRAPPIST-1d using JWST, but we didn't see any atmospheric absorption.
So TRAPPIST-1d is quite different from Earth, despite lying just inside the habitable zone. The planet is either:
➡️ A bare rock.
➡️ Very cloudy.
➡️ Has a thin, Mars-like atmosphere.
#Exoplanets 🔭
So TRAPPIST-1d is quite different from Earth, despite lying just inside the habitable zone. The planet is either:
➡️ A bare rock.
➡️ Very cloudy.
➡️ Has a thin, Mars-like atmosphere.
#Exoplanets 🔭
The TRAPPIST-1 d exoplanet may be Earth-sized 🌍 but it has no Earth-like atmosphere.
Webb’s #NIRSpec has found no traces of molecules that are common in Earth’s atmosphere.
Read more 👉 www.esa.int/Science_Expl... 🔭 🧪
Webb’s #NIRSpec has found no traces of molecules that are common in Earth’s atmosphere.
Read more 👉 www.esa.int/Science_Expl... 🔭 🧪
August 13, 2025 at 5:24 PM
We looked for an atmosphere on TRAPPIST-1d using JWST, but we didn't see any atmospheric absorption.
So TRAPPIST-1d is quite different from Earth, despite lying just inside the habitable zone. The planet is either:
➡️ A bare rock.
➡️ Very cloudy.
➡️ Has a thin, Mars-like atmosphere.
#Exoplanets 🔭
So TRAPPIST-1d is quite different from Earth, despite lying just inside the habitable zone. The planet is either:
➡️ A bare rock.
➡️ Very cloudy.
➡️ Has a thin, Mars-like atmosphere.
#Exoplanets 🔭
Reposted by Gijs D Mulders
Kepler mission: smaller stars have more short-period, small #exoplanets.
Theory: the smallest stars won’t have enough disk material to make small planets so there must be a turnover.
Kepler+K2: We have found a turnover!
Check out our newest Scaling K2 paper: arxiv.org/abs/2508.05734
🧵 1/9
🔭🧪☄️
Theory: the smallest stars won’t have enough disk material to make small planets so there must be a turnover.
Kepler+K2: We have found a turnover!
Check out our newest Scaling K2 paper: arxiv.org/abs/2508.05734
🧵 1/9
🔭🧪☄️
Scaling K2 VIII: Short-Period Sub-Neptune Occurrence Rates Peak Around Early-Type M Dwarfs
We uniformly combined data from the NASA Kepler and K2 missions to compute planet occurrence rates across the entire FGK and M dwarf stellar range. The K2 mission, driven by targets selected by guest ...
arxiv.org
August 11, 2025 at 1:01 AM
Kepler mission: smaller stars have more short-period, small #exoplanets.
Theory: the smallest stars won’t have enough disk material to make small planets so there must be a turnover.
Kepler+K2: We have found a turnover!
Check out our newest Scaling K2 paper: arxiv.org/abs/2508.05734
🧵 1/9
🔭🧪☄️
Theory: the smallest stars won’t have enough disk material to make small planets so there must be a turnover.
Kepler+K2: We have found a turnover!
Check out our newest Scaling K2 paper: arxiv.org/abs/2508.05734
🧵 1/9
🔭🧪☄️
Reposted by Gijs D Mulders
I have a complaint about Avi Loeb's latest work and I want to speak to management.
medium.com/@steve.desch...
medium.com/@steve.desch...
This is not the quality of pseudoscience infotainment to which I have grown accustomed
Teasing the public with fraudulent or self-deluded promises of aliens used to mean something. It took work. It meant slapping together…
medium.com
August 8, 2025 at 6:24 PM
I have a complaint about Avi Loeb's latest work and I want to speak to management.
medium.com/@steve.desch...
medium.com/@steve.desch...
Reposted by Gijs D Mulders
Images from Palomar at 2 different infrared wavelengths last night - one that Saturn's methane atmosphere absorbs, and one the it reflects!
(The faint point source is the moon, Tethys!)
Taken by David Ciardi, Catherine Clark,
@lowbacca.bsky.social and Miranda Felsmann; animated by me (and ezgif!)
(The faint point source is the moon, Tethys!)
Taken by David Ciardi, Catherine Clark,
@lowbacca.bsky.social and Miranda Felsmann; animated by me (and ezgif!)
August 6, 2025 at 6:05 PM
Images from Palomar at 2 different infrared wavelengths last night - one that Saturn's methane atmosphere absorbs, and one the it reflects!
(The faint point source is the moon, Tethys!)
Taken by David Ciardi, Catherine Clark,
@lowbacca.bsky.social and Miranda Felsmann; animated by me (and ezgif!)
(The faint point source is the moon, Tethys!)
Taken by David Ciardi, Catherine Clark,
@lowbacca.bsky.social and Miranda Felsmann; animated by me (and ezgif!)
Reposted by Gijs D Mulders
I really like this graphical summary of the architectures of planetary systems from @sidereuskinch.bsky.social's talk at From Transits to Trends!
August 7, 2025 at 4:02 PM
I really like this graphical summary of the architectures of planetary systems from @sidereuskinch.bsky.social's talk at From Transits to Trends!
Reposted by Gijs D Mulders
New paper! Allow me to introduce TARS = Torqued Accelerator using Radiation from the Sun. TARS (yes inspired by Interstellar!) is a rotating light sail that's capable of launching chip sats into interstellar space using only radiation from the Sun, so let's dive into how it works.
July 26, 2025 at 4:17 PM
New paper! Allow me to introduce TARS = Torqued Accelerator using Radiation from the Sun. TARS (yes inspired by Interstellar!) is a rotating light sail that's capable of launching chip sats into interstellar space using only radiation from the Sun, so let's dive into how it works.
Reposted by Gijs D Mulders
The main takeaway of my talk, in the style of the ‘Behold my field of fucks and see that it is barren’ embroidery:
July 26, 2025 at 12:37 AM
The main takeaway of my talk, in the style of the ‘Behold my field of fucks and see that it is barren’ embroidery:
Reposted by Gijs D Mulders
What does the radius valley tell about the planet formation scenario around low mass stars? And how does it connect it with water worlds? To know more, come visit my poster #37 at SSW2025. #sagan2025 #exoplanets
July 23, 2025 at 6:46 PM
What does the radius valley tell about the planet formation scenario around low mass stars? And how does it connect it with water worlds? To know more, come visit my poster #37 at SSW2025. #sagan2025 #exoplanets
Reposted by Gijs D Mulders
Want to learn about the relationship between planet size and orbital eccentricity? Read this thread! 🧪 🔭 🪐
July 17, 2025 at 8:28 PM
Want to learn about the relationship between planet size and orbital eccentricity? Read this thread! 🧪 🔭 🪐