Linn Boldt-Christmas
@nplinnspace.bsky.social
🇸🇪 Exoplanet atmospheres + chemistry + formation at Uppsala University 🪐🔭 Also into astrobiology, policy, climate, equality/EDI, and scicomm ✨ (she/her) – linnboldtchristmas.wordpress.com
Pinned
VLT/CRIRES+ observations of warm Neptune WASP-107 b: Molecular detections and challenges in ground-based transmission spectroscopy of cooler and cloudy exoplanets
Atmospheres of transiting exoplanets can be studied spectroscopically using space-based or ground-based observations. Each has its own strengths and weaknesses, so there are benefits to both approache...
arxiv.org
Do you love WASP-107 b? Do you love making use of *both* ground VLT + space JWST obs to detect molecules in a "warm" (Teq<800K) #exoplanet in transmission, even in a crazy confusing cloudy atmosphere?!
🚨 It's PAPER* DAY! Which means #scicomm thread!
🧵⬇️🔭🪐🧪
*pre-print!
arxiv.org/abs/2508.18964
🚨 It's PAPER* DAY! Which means #scicomm thread!
🧵⬇️🔭🪐🧪
*pre-print!
arxiv.org/abs/2508.18964
Some #astrobiology reading for a Saturday morning: I really enjoyed this pop sci BBC article on finding biology like mould and frogs (!) adapting to life in radioactive Chernobyl by increasing melanin, i.e. what shields human skin from UV rays 🧪🔭 ”Life, uh, finds a way”
www.bbc.com/future/artic...
www.bbc.com/future/artic...
The mysterious black fungus from Chernobyl that may eat radiation
Mould found at the site of the Chernobyl nuclear disaster appears to be feeding off the radiation. Could we use it to shield space travellers from cosmic rays?
www.bbc.com
November 29, 2025 at 9:34 AM
Some #astrobiology reading for a Saturday morning: I really enjoyed this pop sci BBC article on finding biology like mould and frogs (!) adapting to life in radioactive Chernobyl by increasing melanin, i.e. what shields human skin from UV rays 🧪🔭 ”Life, uh, finds a way”
www.bbc.com/future/artic...
www.bbc.com/future/artic...
Reposted by Linn Boldt-Christmas
Well... shit. This one is new to me.
I look forward to hearing more about this from #SpaceWeather folks!
Apparently, the Jetblue incident that kicked this off happened a month ago: www.cnn.com/2025/10/30/u...
🧪🔭
I look forward to hearing more about this from #SpaceWeather folks!
Apparently, the Jetblue incident that kicked this off happened a month ago: www.cnn.com/2025/10/30/u...
🧪🔭
November 29, 2025 at 1:50 AM
Well... shit. This one is new to me.
I look forward to hearing more about this from #SpaceWeather folks!
Apparently, the Jetblue incident that kicked this off happened a month ago: www.cnn.com/2025/10/30/u...
🧪🔭
I look forward to hearing more about this from #SpaceWeather folks!
Apparently, the Jetblue incident that kicked this off happened a month ago: www.cnn.com/2025/10/30/u...
🧪🔭
Reposted by Linn Boldt-Christmas
6,000 #exoplanets have been found to date, but ZERO of them are Earth-like planets around Sun-like stars! Why is that? Do any exist? Or is it just hard? ☀️🌍🔭
Join us on Thu 4 Dec @ 14:00 UTC for a #RockyWorldsDiscussion with Annelies Mortier to find out!
More: www.rockyworlds.org/event-detail... ☄️🧪
Join us on Thu 4 Dec @ 14:00 UTC for a #RockyWorldsDiscussion with Annelies Mortier to find out!
More: www.rockyworlds.org/event-detail... ☄️🧪
November 28, 2025 at 1:36 PM
6,000 #exoplanets have been found to date, but ZERO of them are Earth-like planets around Sun-like stars! Why is that? Do any exist? Or is it just hard? ☀️🌍🔭
Join us on Thu 4 Dec @ 14:00 UTC for a #RockyWorldsDiscussion with Annelies Mortier to find out!
More: www.rockyworlds.org/event-detail... ☄️🧪
Join us on Thu 4 Dec @ 14:00 UTC for a #RockyWorldsDiscussion with Annelies Mortier to find out!
More: www.rockyworlds.org/event-detail... ☄️🧪
Reposted by Linn Boldt-Christmas
Dan Valentine (@danvalentine.bsky.social) has done some great work looking at using ARIEL to eclipse map exoplanet atmospheres. #exoplanets #astronomy
www.youtube.com/watch?v=lrtL...
www.youtube.com/watch?v=lrtL...
Eclipse Mapping with Ariel: Future Prospects for a Population-Level Mapping Survey
YouTube video by BOWIE+ Seminars
www.youtube.com
November 28, 2025 at 8:54 AM
Dan Valentine (@danvalentine.bsky.social) has done some great work looking at using ARIEL to eclipse map exoplanet atmospheres. #exoplanets #astronomy
www.youtube.com/watch?v=lrtL...
www.youtube.com/watch?v=lrtL...
Reposted by Linn Boldt-Christmas
Reading through ESA's draft #CM25 resolution on the level of resources to be committed between now and 2030 - strong support for the proposal to complete #CosmicVision and get #Voyage2050 (M7, L4) underway. Particularly like that line on international flagship partnerships (HabWorlds? Uranus?).
November 27, 2025 at 7:20 PM
Reading through ESA's draft #CM25 resolution on the level of resources to be committed between now and 2030 - strong support for the proposal to complete #CosmicVision and get #Voyage2050 (M7, L4) underway. Particularly like that line on international flagship partnerships (HabWorlds? Uranus?).
🔭 The new @esa.int budget secured today is a big deal imho. +30% compared to the current budget with largest chunk going to space transportation ie 🚀. Science/astro is also getting a big bump, which DG Aschbacher called ”the backbone of the ESA programme”. Some funding optimism to close off 2025! 💫🥹
22.1 billion euros subscribed.
A record.
A first.
And a clear message that Europe is serious about space and that @esa.int is the agency it trusts to deliver.
A historic Ministerial. A united Europe. A stronger ESA.
www.esa.int/About_Us/Cor...
A record.
A first.
And a clear message that Europe is serious about space and that @esa.int is the agency it trusts to deliver.
A historic Ministerial. A united Europe. A stronger ESA.
www.esa.int/About_Us/Cor...
ESA Member States commit to largest contributions at Ministerial
The largest contributions in the history of the European Space Agency, €22.1 bn, have been approved at its Council meeting at Ministerial level in Bremen, ...
www.esa.int
November 27, 2025 at 7:06 PM
🔭 The new @esa.int budget secured today is a big deal imho. +30% compared to the current budget with largest chunk going to space transportation ie 🚀. Science/astro is also getting a big bump, which DG Aschbacher called ”the backbone of the ESA programme”. Some funding optimism to close off 2025! 💫🥹
Reposted by Linn Boldt-Christmas
22.1 billion euros subscribed.
A record.
A first.
And a clear message that Europe is serious about space and that @esa.int is the agency it trusts to deliver.
A historic Ministerial. A united Europe. A stronger ESA.
www.esa.int/About_Us/Cor...
A record.
A first.
And a clear message that Europe is serious about space and that @esa.int is the agency it trusts to deliver.
A historic Ministerial. A united Europe. A stronger ESA.
www.esa.int/About_Us/Cor...
ESA Member States commit to largest contributions at Ministerial
The largest contributions in the history of the European Space Agency, €22.1 bn, have been approved at its Council meeting at Ministerial level in Bremen, ...
www.esa.int
November 27, 2025 at 4:26 PM
22.1 billion euros subscribed.
A record.
A first.
And a clear message that Europe is serious about space and that @esa.int is the agency it trusts to deliver.
A historic Ministerial. A united Europe. A stronger ESA.
www.esa.int/About_Us/Cor...
A record.
A first.
And a clear message that Europe is serious about space and that @esa.int is the agency it trusts to deliver.
A historic Ministerial. A united Europe. A stronger ESA.
www.esa.int/About_Us/Cor...
Reposted by Linn Boldt-Christmas
Putting a general call out to my private sector colleagues - would anyone be interested in supporting an industry PhD?
I would love to bring in students to work on imaging/time series problems, especially in space/remote sensing bridging astronomy and other applications.
I would love to bring in students to work on imaging/time series problems, especially in space/remote sensing bridging astronomy and other applications.
CSIRO Industry PhD Program: Information for industry
Tackle your business challenge. Gain access to top research and development expertise while developing the next generation of researchers.
www.csiro.au
November 27, 2025 at 8:45 AM
Putting a general call out to my private sector colleagues - would anyone be interested in supporting an industry PhD?
I would love to bring in students to work on imaging/time series problems, especially in space/remote sensing bridging astronomy and other applications.
I would love to bring in students to work on imaging/time series problems, especially in space/remote sensing bridging astronomy and other applications.
Reposted by Linn Boldt-Christmas
Amazing thread: every time we expand the range of what's possible for terrestrial extremophiles, the likelihood life exists elsewhere in the galaxy goes up for me.
So happy to announce our new preprint, “A geothermal amoeba sets a new upper temperature limit for eukaryotes.” We cultured a novel amoeba from Lassen Volcanic NP (CA, USA) that divides at 63°C (145°F) 🔥 - a new record for euk growth!
#protistsonsky 🧵
#protistsonsky 🧵
November 25, 2025 at 10:34 PM
Amazing thread: every time we expand the range of what's possible for terrestrial extremophiles, the likelihood life exists elsewhere in the galaxy goes up for me.
Reposted by Linn Boldt-Christmas
🔭🧪🎢 PhD Project focus: Novel Pu Gd oxides for Space Nuclear Power Systems
We're advertising this project with Dr Emily Jane Watkinson, investigating new options to power exploration of the outer solar system
For details of all our PhD projects look here: le.ac.uk/study/resear... 🔭🧪🎢
We're advertising this project with Dr Emily Jane Watkinson, investigating new options to power exploration of the outer solar system
For details of all our PhD projects look here: le.ac.uk/study/resear... 🔭🧪🎢
STFC | Postgraduate research | University of Leicester
STFC Studentships in Physics and Astronomy. University of Leicester
le.ac.uk
November 25, 2025 at 12:19 PM
🔭🧪🎢 PhD Project focus: Novel Pu Gd oxides for Space Nuclear Power Systems
We're advertising this project with Dr Emily Jane Watkinson, investigating new options to power exploration of the outer solar system
For details of all our PhD projects look here: le.ac.uk/study/resear... 🔭🧪🎢
We're advertising this project with Dr Emily Jane Watkinson, investigating new options to power exploration of the outer solar system
For details of all our PhD projects look here: le.ac.uk/study/resear... 🔭🧪🎢
Reposted by Linn Boldt-Christmas
That is an ex-comet
Fantastic work by Ariel Graykowski and our @setiinstitute.bsky.social citizen scientists.
Comet C/2025 K1 (ATLAS) is breaking apart — and some of you caught it live. After passing 0.3 AU from the Sun, it erupted, and three days later a third appeared.
K1 is now officially in pieces.
Comet C/2025 K1 (ATLAS) is breaking apart — and some of you caught it live. After passing 0.3 AU from the Sun, it erupted, and three days later a third appeared.
K1 is now officially in pieces.
November 25, 2025 at 6:09 AM
That is an ex-comet
Reposted by Linn Boldt-Christmas
If your planet's not too big, and your transit spectrum is flatter than you'd think, your aerosols might be clumpy.
Owen+ arxiv.org/abs/2511.19013
🧪🔭🪐 #exoplanets
Owen+ arxiv.org/abs/2511.19013
🧪🔭🪐 #exoplanets
Resolving the flat-spectrum conundrum: clumpy aerosol distributions in sub-Neptune atmospheres
Transmission spectroscopy of sub-Neptunes was expected to reveal their compositions and hence origins, yet many show flat near- to mid-infrared spectra. Such spectra can be explained either by metal d...
arxiv.org
November 25, 2025 at 8:32 AM
If your planet's not too big, and your transit spectrum is flatter than you'd think, your aerosols might be clumpy.
Owen+ arxiv.org/abs/2511.19013
🧪🔭🪐 #exoplanets
Owen+ arxiv.org/abs/2511.19013
🧪🔭🪐 #exoplanets
Reposted by Linn Boldt-Christmas
Norway’s icy landscapes are a dream for both Northern lights lovers and space fanatics.
🇳🇴
In 1987 Norway became a full member of @esa.int and these are the country's contributions to Europe's heavy-lift rocket #Ariane6
🚀
www.esa.int/Enabling_Sup...
🇳🇴
In 1987 Norway became a full member of @esa.int and these are the country's contributions to Europe's heavy-lift rocket #Ariane6
🚀
www.esa.int/Enabling_Sup...
November 24, 2025 at 4:11 PM
Norway’s icy landscapes are a dream for both Northern lights lovers and space fanatics.
🇳🇴
In 1987 Norway became a full member of @esa.int and these are the country's contributions to Europe's heavy-lift rocket #Ariane6
🚀
www.esa.int/Enabling_Sup...
🇳🇴
In 1987 Norway became a full member of @esa.int and these are the country's contributions to Europe's heavy-lift rocket #Ariane6
🚀
www.esa.int/Enabling_Sup...
Reposted by Linn Boldt-Christmas
We are hiring a new Assistant Professor in Astrophysics at Trinity College Dublin!! ☘
Job ad here: aas.org/jobregister/...
Deadline: Jan 02 2026
Please share widely! 🪐🔭
Job ad here: aas.org/jobregister/...
Deadline: Jan 02 2026
Please share widely! 🪐🔭
Assistant Professor in Astrophysics | American Astronomical Society
The School of Physics at Trinity College Dublin invites applications for a position at the level of Assistant Professor in the field of observational or theoretical astrophysics. We seek motivated ind...
aas.org
November 24, 2025 at 12:27 PM
We are hiring a new Assistant Professor in Astrophysics at Trinity College Dublin!! ☘
Job ad here: aas.org/jobregister/...
Deadline: Jan 02 2026
Please share widely! 🪐🔭
Job ad here: aas.org/jobregister/...
Deadline: Jan 02 2026
Please share widely! 🪐🔭
🔭🧪 A+ thread below summarising what kind of incoming asteroids/objects we can, cannot, and *kind of* can track ahead of impact and thus protect ourselves from ⬇️
Then decide for yourself if you find it reassuring or not…
Then decide for yourself if you find it reassuring or not…
OK, so. Below a certain size, the atmosphere takes care of the problem--objects below 10 meters in size, say, are going to give a great showy fireball but not do any damage on the ground unless you're really personally unlucky, like the teenager who owned this car.
meteoritecar.com
meteoritecar.com
The Peekskill Meteorite Car Official Website
The official website of the Peekskill Meteorite Car, the most famous object to ever be struck by a meteorite.
meteoritecar.com
November 22, 2025 at 1:32 PM
🔭🧪 A+ thread below summarising what kind of incoming asteroids/objects we can, cannot, and *kind of* can track ahead of impact and thus protect ourselves from ⬇️
Then decide for yourself if you find it reassuring or not…
Then decide for yourself if you find it reassuring or not…
Reposted by Linn Boldt-Christmas
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)
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)
Reposted by Linn Boldt-Christmas
It’s widely known (and, I think, pretty uncontroversial) that learning requires effort — specifically, if you don’t have to work at getting the knowledge, it won’t stick.
Even if an LLM could be trusted to give you correct information 100% of the time, it would be an inferior method of learning it.
Even if an LLM could be trusted to give you correct information 100% of the time, it would be an inferior method of learning it.
Relying on ChatGPT to teach you about a topic leaves you with shallower knowledge than Googling and reading about it, according to new research that compared what more than 10,000 people knew after using one method or the other.
Shared by @gizmodo.com: buff.ly/yAAHtHq
Shared by @gizmodo.com: buff.ly/yAAHtHq
November 21, 2025 at 12:49 PM
It’s widely known (and, I think, pretty uncontroversial) that learning requires effort — specifically, if you don’t have to work at getting the knowledge, it won’t stick.
Even if an LLM could be trusted to give you correct information 100% of the time, it would be an inferior method of learning it.
Even if an LLM could be trusted to give you correct information 100% of the time, it would be an inferior method of learning it.
Reposted by Linn Boldt-Christmas
There are about 400 photons and 300 neutrinos in every cubic cm of the Universe left over from the Big Bang 🧪
Man, everything is so bleak, anyone got a fun fact or little bit of trivia they want to share
November 21, 2025 at 12:41 PM
There are about 400 photons and 300 neutrinos in every cubic cm of the Universe left over from the Big Bang 🧪
Reposted by Linn Boldt-Christmas
We have a PhD opportunity at the University of Reading focused on analysing Jupiter and Saturn auroral observations!
Title: Investigating Earth-like responses to the Solar Wind in Gas Giant Upper Atmospheres
Supervisor: me!
Full description/application portal:
www.findaphd.com/phds/project...
Title: Investigating Earth-like responses to the Solar Wind in Gas Giant Upper Atmospheres
Supervisor: me!
Full description/application portal:
www.findaphd.com/phds/project...
Crocus DLA
crocus-dla.ac.uk
November 20, 2025 at 2:11 PM
We have a PhD opportunity at the University of Reading focused on analysing Jupiter and Saturn auroral observations!
Title: Investigating Earth-like responses to the Solar Wind in Gas Giant Upper Atmospheres
Supervisor: me!
Full description/application portal:
www.findaphd.com/phds/project...
Title: Investigating Earth-like responses to the Solar Wind in Gas Giant Upper Atmospheres
Supervisor: me!
Full description/application portal:
www.findaphd.com/phds/project...
🔭🧪 Absolutely blown away by the pedagogy and the *artistry* of this goliath piece of #scicomm ⬇️ Just look at these drawings!!
This must have taken an incredible amount of time & talent, and I learned so much (about a fairly-distant-subfield-to-mine) from it! So grateful for scientists who do this!
This must have taken an incredible amount of time & talent, and I learned so much (about a fairly-distant-subfield-to-mine) from it! So grateful for scientists who do this!
November 20, 2025 at 7:31 AM
🔭🧪 Absolutely blown away by the pedagogy and the *artistry* of this goliath piece of #scicomm ⬇️ Just look at these drawings!!
This must have taken an incredible amount of time & talent, and I learned so much (about a fairly-distant-subfield-to-mine) from it! So grateful for scientists who do this!
This must have taken an incredible amount of time & talent, and I learned so much (about a fairly-distant-subfield-to-mine) from it! So grateful for scientists who do this!
Reposted by Linn Boldt-Christmas
To finish it off, I've also done an annotated version of the paper complete with silly drawings and accessible language! These are inspired by @clairelamman.bsky.social , and you can read this and more here: ryanwhite1.github.io/wolf-rayet.h...
4/4 ⚛️🔭🧪
4/4 ⚛️🔭🧪
November 19, 2025 at 10:18 PM
To finish it off, I've also done an annotated version of the paper complete with silly drawings and accessible language! These are inspired by @clairelamman.bsky.social , and you can read this and more here: ryanwhite1.github.io/wolf-rayet.h...
4/4 ⚛️🔭🧪
4/4 ⚛️🔭🧪
Reposted by Linn Boldt-Christmas
First time in a while where I’ve had the “wait that’s an IMAGE. That’s the DATA.” double take.
Very excited to share the NASA/ESA/STScI press release of our team's work on Apep! It's a terrific writeup, complete with a brand new beautiful visualisation of the nebula geometry.
1/? ⚛️🔭🧪
science.nasa.gov/missions/web...
1/? ⚛️🔭🧪
science.nasa.gov/missions/web...
Webb First to Show 4 Dust Shells 'Spiraling' Apep, Limits Long Orbit - NASA Science
NASA’s James Webb Space Telescope has delivered a first of its kind: a crisp mid-infrared image of a system of four serpentine spirals of dust, one expanding
science.nasa.gov
November 20, 2025 at 12:14 AM
First time in a while where I’ve had the “wait that’s an IMAGE. That’s the DATA.” double take.
Reposted by Linn Boldt-Christmas
Remember that lovely aurora last week?
Well...um...this is what Euclid saw... 😱
🧵
Well...um...this is what Euclid saw... 😱
🧵
November 19, 2025 at 11:51 AM
Remember that lovely aurora last week?
Well...um...this is what Euclid saw... 😱
🧵
Well...um...this is what Euclid saw... 😱
🧵
Reposted by Linn Boldt-Christmas
If you live in France, a new documentary about 'Oumuamua comes out Thursday evening, starting at 9pm on the France 5. Replays on france.tv after
I was scientific advisor (and I show up in several places), which was a great pleasure.
www.francetvpro.fr/contenu-de-p...
I was scientific advisor (and I show up in several places), which was a great pleasure.
www.francetvpro.fr/contenu-de-p...
France TV - Replay et Direct tv des chaînes France Télévisions (ex Pluzz)
Retrouvez toutes les vidéos, articles et podcasts des programmes des chaînes de France Télévisions.
france.tv
November 18, 2025 at 11:21 AM
If you live in France, a new documentary about 'Oumuamua comes out Thursday evening, starting at 9pm on the France 5. Replays on france.tv after
I was scientific advisor (and I show up in several places), which was a great pleasure.
www.francetvpro.fr/contenu-de-p...
I was scientific advisor (and I show up in several places), which was a great pleasure.
www.francetvpro.fr/contenu-de-p...
Reposted by Linn Boldt-Christmas
collaborative proposal writing tip:
start the narrative out with one font size larger than the minimum allowed. Then in the final days when everyone is squeezed for space, drop down to the proper font size. This forces everyone to write more concisely from the start.
start the narrative out with one font size larger than the minimum allowed. Then in the final days when everyone is squeezed for space, drop down to the proper font size. This forces everyone to write more concisely from the start.
November 17, 2025 at 6:55 PM
collaborative proposal writing tip:
start the narrative out with one font size larger than the minimum allowed. Then in the final days when everyone is squeezed for space, drop down to the proper font size. This forces everyone to write more concisely from the start.
start the narrative out with one font size larger than the minimum allowed. Then in the final days when everyone is squeezed for space, drop down to the proper font size. This forces everyone to write more concisely from the start.