Matthieu Le Lain
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Matthieu Le Lain
@matlastro.bsky.social
160 followers 900 following 1 posts
Astronomy and astrophysics sprinkled with Deep Learning... or the other way around ! PhD student working on Foundation Models for Astronomy. #galaxy
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Reposted by Matthieu Le Lain
guillaumebertrand.bsky.social
Très fier d’avoir reçu le Grand Prix de l’innovation SAF ! 🏆 Nous avons été récompensés par la Société astronomique de France et son président, Roland Lehoucq pour le projet #SUNSCAN by #STAROS. Une réussite collective avec V. Desnoux, C. Buil, O. Garde et Matthieu Le Lain (@matlastro.bsky.social)
November 30, 2025 at 9:07 AM
Reposted by Matthieu Le Lain
drnereide.bsky.social
Exceptional!

The faint blur you see in this NIRCam image refers to GS-NDG-9422, a "strange" galaxy identified with the JWST and announced in 2024.

➡️ science.nasa.gov/missions/web...

Credits: NASA, ESA, CSA, STScI, Alex Cameron (Oxford)

🔭 🧪 #science #extragalactic #cosmology #JWST #Webb

1/5
Pure black cosmos dotted with hundreds of tiny white, gold, pink, and blue specks—distant galaxies. Top-left: target galaxy GS-NDG-9422 inside a crisp white square box, just a faint, barely-there reddish smudge, almost invisible. A larger inset with white frame near the center zooms it in, turning that pale glow soft orange.That tiny boxed reddish puff on the left feels incredibly old and delicate—a whisper from the universe at one billion years young.
November 29, 2025 at 6:20 PM
Reposted by Matthieu Le Lain
astroarxiv.bsky.social
Orbital parameters of the bright binary alpha Draconis based on amateur spectra from the STAROS database. G. Bertrand et. al. https://arxiv.org/abs/2511.17206
Figure 1 Figure 2 Figure 3 Figure 4
November 24, 2025 at 7:06 AM
Reposted by Matthieu Le Lain
drnereide.bsky.social
Gaia will find ~120,000 exoplanets, mostly super-Jupiters!

From 2014–2025 at L2, it tracked >1B stars so precisely: a pinhead on the Moon from Earth!

Full data by 2030; first release predicts 7,500 planets.

Also: hypervelocity stars, quad systems & ancient galaxy merger remnants. 🔭 🧪 #science
johncarlosbaez.bsky.social John C. Baez @johncarlosbaez.bsky.social · 22d
When you repeatedly measure the positions of over a billion stars so accurately that you can see a star moving by an amount equal to the size of a pinhead on the Moon, as seen from Earth... you find amazing things!

It's great.

mathstodon.xyz/@johncarlosb...
John Carlos Baez (@johncarlosbaez@mathstodon.xyz)
Holy crap! The Gaia space telescope is expected to find 120,000 ± 22,000 planets orbiting other stars! Most will be super-Jupiters, because those are the easiest to find. But we'll know much more ...
mathstodon.xyz
November 12, 2025 at 9:36 AM
Reposted by Matthieu Le Lain
minouette.bsky.social
For Day 21 of #spacetober_challenge prompt star: trailblazing US #astronomer Annie Jump Cannon (1863 – 1941), here with her stellar classification system which sorted stars based on spectral types, revealing their temperature from hot blue to cool red stars: O,B,A, F, G, K & M. 🧪🐡👩🏼‍🔬🔭#histsci 🧵
My linocut of Annie Jump Cannon shows her in a 3/4 profile view wearing a shirt with a lace collar and her hair up. She is printed in a gradient of violet at the bottom to green at the top, printed on white 11” x 14” paper. The background is printed in a gradient (left to right) of dark blue, light blue, yellow, pale yellow, pale orange, orange and red. The background block excludes her silhouette of shoulder and head with the exception of a smattering of small dots in a swath from upper left to lower right (which extends to white spots on the coloured background). Also along the bottom are a series of circles of decreasing size (left to right, blue through red) labelled O, B, A, F, G, K, M. There’s a axis line along the bottom with 6 tick marks. Vertically from top to bottom along the left side are 15-, 10-, 5-, 0, 5, 20, 15.
October 21, 2025 at 11:33 AM
Reposted by Matthieu Le Lain
siril.org
Bonne nouvelle pour les francophones, le livre sur Siril est disponible à la précommande, avec une réduction valable tout le mois de septembre !!
siril.fr/commander/
Commander | Siril - Le livre de référence
siril.fr
September 1, 2025 at 4:04 PM
Reposted by Matthieu Le Lain
brettmorr.is
Sweet NASA feature article on @sabinastro.bsky.social's work on mapping stellar surfaces: 🔭🧪 #stellarastro

science.nasa.gov/missions/tes...

Why? Because:
1) #StarsAreStillInteresting
2) Messy stars complicate our view of exoplanet atmospheres. To remove stellar contamination, you must map it. 🗺️
Astronomers Map Stellar ‘Polka Dots’ Using NASA’s TESS, Kepler - NASA Science
Scientists have devised a new method for mapping the spottiness of distant stars by using observations from NASA missions of orbiting planets crossing their
science.nasa.gov
August 25, 2025 at 3:34 PM
Reposted by Matthieu Le Lain
chrislintott.bsky.social
Betelgeuse is a double! Fun to learn something new about a familiar star.
July 21, 2025 at 7:09 PM
Reposted by Matthieu Le Lain
niamhk12.bsky.social
It’s paper day 🎉!! If you are interested in seeing how supergranulation changes over a solar cycle in RVs give it a read! arxiv.org/abs/2506.23693
Measuring the Suns radial velocity variability due to supergranulation over a magnetic cycle
In recent years supergranulation has emerged as one of the biggest challenges for the detection of Earth-twins in radial velocity planet searches. We used eight years of Sun-as-a-star radial velocity ...
arxiv.org
July 1, 2025 at 8:07 AM
Reposted by Matthieu Le Lain
astroarxiv.bsky.social
Spectroastrometry and Reverberation Mapping of Active Galactic Nuclei. II. Measuring Geometric Distances and Black Hole Masses of Four Nearby Quasars. Yan-Rong Li et. al. https://arxiv.org/abs/2502.18856
Figure 1 Figure 2 Figure 3 Figure 4
July 1, 2025 at 9:05 AM
Reposted by Matthieu Le Lain
whereisyvette.bsky.social
MY FIRST EVER ARTICLE FOR SCIENTIFIC AMERICAN IS OUT!!!

It's all about how black holes shred stars and how we discovered that black holes "burp" after eating them, and even includes a black hole called Jetty McJetface! What's not to love? 🤩

www.scientificamerican.com/article/why-...

🔭🧪🎢
Cosmic Indigestion Is Causing Black Holes to Spit Up Stars
After black holes devour stars, sometimes the feast comes back up
www.scientificamerican.com
June 18, 2025 at 10:40 PM
Reposted by Matthieu Le Lain
emily.space
Finding out about Gaia at #EAS2025Cork! ☄️

Just announced: Gaia DR4 will be released in December 2026!
A photo of the slide with the December 2026 release date
June 26, 2025 at 2:11 PM
Reposted by Matthieu Le Lain
guillaumebertrand.bsky.social
Here's a cool spectro and photometry experiment to measure the mass of supermassive black holes from your backyard :) Based on single-epoch estimators in broad-line AGN. 🌈🔭 #astrophysics #astronomy #spectroscopy #photometry

guillaumebertrand.notion.site/Estimating-b...
June 26, 2025 at 11:43 AM
Reposted by Matthieu Le Lain
astrogeorges.bsky.social
Happy to announce that the line-detector.oca.eu website is now online!
It allows the user to select the stellar type, [M/H], λ- range, and resolving power and the page returns:
-purity of the line and minimum S/N required to detect it.
-interactive plot to identify the lines in the spectra
June 23, 2025 at 7:25 AM
Reposted by Matthieu Le Lain
We found the most distant confirmed galaxy
(some Sergej Boebka vibes 😅)

arxiv.org/abs/2505.11263
May 19, 2025 at 6:42 AM
Reposted by Matthieu Le Lain
brettmorr.is
This is the globular cluster M15, imaged by Hubble. It's a great target for binoculars or backyard telescopes, in the constellation Pegasus.

Jiaqi Ying et al. measured M15's age with 3% precision. This group of stars formed *immediately* after the Universe did.

arxiv.org/abs/2505.02969

🔭🧪 #stars
This cluster of stars is known as Messier 15, and is located some 35,000 light-years away in the constellation of Pegasus (The Winged Horse). It is one of the oldest globular clusters known, with an age of around 12 billion years. This new image is made up of observations from Hubble's Wide Field Camera 3 and Advanced Camera for Surveys in the ultraviolet, infrared, and optical parts of the spectrum. (NASA, ESA) Figure 1. Comparing two theoretical isochrones we constructed with different ages, MC parameters, distance, and reddening. The observational data for M15 is plotted in the background, with photometric uncertainty estimated from the AS test plotted on the right.
May 7, 2025 at 4:13 PM
Reposted by Matthieu Le Lain
karenlmasters.bsky.social
Been an exciting week for @galaxyzoo.org - our relaunch with JWST imaging has resulted in highest daily classification rate since March 2020. www.galaxyzoo.org. 🔭👩‍🔬🎉
Zooniverse
The Zooniverse is the world’s largest and most popular platform for people-powered research.
Www.galaxyzoo.org
May 1, 2025 at 1:12 PM
Reposted by Matthieu Le Lain
emily.space
Interested in stellar physics? Orlagh L. Creevey has posted their lecture notes & recorded lecture from a day-long introduction to stellar physics with Gaia!

#astroedu #stellarastro 🔭 🧪
Stellar Physics Across the HR Diagram with Gaia
Gaia Data Release 3 (GDR3) contains a wealth of information to advance our knowledge of stellar physics. In these lecture notes we introduce the data products from GDR3 that can be exploited by the st...
arxiv.org
April 28, 2025 at 6:52 AM
Reposted by Matthieu Le Lain
henstr.bsky.social
The new official paper/poster browser for ICLR 2025 is out.
Enjoy!

iclr2025.vizhub.ai

#iclr #ai #iclr2025
April 18, 2025 at 4:21 PM
Reposted by Matthieu Le Lain
universetbd.org
📢 New dataset out!

We introduce HypoGen💥, a dataset of ~5.5K structured problem–hypothesis pairs (Bit–Flip–Spark + Chain‑of‑Reasoning) to advance LLM-driven scientific ideation💡.

Fine‑tuned LLaMA 3.1 8B & R1‑distilled models show significant gains. Humans are still the best🥇.
April 18, 2025 at 5:57 PM
Reposted by Matthieu Le Lain
universetbd.org
Excited to announce our new paper as part of our 2^2 week: AstroLLaVA, a vision language model for astronomy that enables natural dialogue with astronomical imagery! Shout out to Sharaf Zaman for leading this work arxiv.org/abs/2504.08583 🔭☄️
April 16, 2025 at 12:17 PM
Reposted by Matthieu Le Lain
mjjsmith.com
Was great fun cooking this up with Sharaf and team! Check out all the code at github.com/UniverseTBD/... and paper at arxiv.org/abs/2504.08583
April 16, 2025 at 12:19 PM
Reposted by Matthieu Le Lain
sf2a.bsky.social
PRIX DE THESE #SF2A 2025: Le conseil de la SF2A a l'honneur de décerner le prix de thèse 2025 à Giulia Pagnini pour sa thèse: "L'évolution précoce et tardive de notre Galaxie à travers la lentille des amas globulaires", au laboratoire GEPI, observatoire de Paris, sous la direction de P. Di Matteo.
sf2a.eu
April 12, 2025 at 6:58 AM
Reposted by Matthieu Le Lain
emily.space
Nice paper out today by Francisco Carrasco-Varela et al. looking at blue straggler stars in #galactic open and globular clusters! ☄️ #stellarastro

These weird stars form in mergers, and in their comprehensive survey they find an increasing fraction with age and multiple 'bumps' over time.
Their Figure 11, showing the location of blue straggler stars (BSSs) in two of the clusters they study Their figure 3, showing the changing number of blue stragglers as a function of age. Especially the bottom plot, where it's normalized - it's bumpy!
March 28, 2025 at 8:58 AM
Reposted by Matthieu Le Lain
emily.space
Anyways, here's the paper - it's one of the first big uses of foundation models in astronomy that I'm aware of, and it seems to have worked really well! #extragalactic #astrocode 🧪
Euclid Quick Data Release (Q1) Exploring galaxy properties with a multi-modal foundation model
Modern astronomical surveys, such as the Euclid mission, produce high-dimensional, multi-modal data sets that include imaging and spectroscopic information for millions of galaxies. These data serve a...
arxiv.org
March 20, 2025 at 11:10 AM