Alexis Quintana
@alexis-space.bsky.social
Astronomy postdoc fellow in LIRA (@liraastro.bsky.social), Paris Observatory (@obs-paris-psl.bsky.social) in 🇨🇵.
Works on OB stars, stellar associations & clusters and Galactic structure & dynamics.
From 🇧🇪, previously in 🇬🇧 and 🇪🇦.
he/him
Works on OB stars, stellar associations & clusters and Galactic structure & dynamics.
From 🇧🇪, previously in 🇬🇧 and 🇪🇦.
he/him
Pinned
Alexis Quintana
@alexis-space.bsky.social
· Aug 19
Most stars form in clusters! 🔭🧪☄️ #galactic
In a new paper led by @alexis-space.bsky.social, we show that >80% of stars in the local Milky Way formed in clusters.
This is *much* higher than other recent estimates (~15%), and supports more traditional 'clustered' models of star formation!
In a new paper led by @alexis-space.bsky.social, we show that >80% of stars in the local Milky Way formed in clusters.
This is *much* higher than other recent estimates (~15%), and supports more traditional 'clustered' models of star formation!
How many stars form in compact clusters in the local Milky Way?
Two main models coexist for the environment in which stars form. The clustered model stipulates that the bulk of star formation occurs within dense embedded clusters, but only a minority of them survi...
arxiv.org
Star formation primarily takes place within compact clusters in the local Milky Way! 🌌 #galactic #stellarastro
We've shown this combining the results from two recent, Gaia-based catalogues: the open clusters census from @emily.space and my census of OB stars within 1 kpc!
We've shown this combining the results from two recent, Gaia-based catalogues: the open clusters census from @emily.space and my census of OB stars within 1 kpc!
The Great Pleaides Complex! A new study, led by Andrew Boyle, identified the diffuse remnants of this cluster and trace them back to the same natal cloud! Truly impressive how much we can learn with Gaia an TESS data even on an open cluster as famous as the Pleaides.
#astro #stellarastro #galactic
#astro #stellarastro #galactic
November 15, 2025 at 3:07 PM
The Great Pleaides Complex! A new study, led by Andrew Boyle, identified the diffuse remnants of this cluster and trace them back to the same natal cloud! Truly impressive how much we can learn with Gaia an TESS data even on an open cluster as famous as the Pleaides.
#astro #stellarastro #galactic
#astro #stellarastro #galactic
That's really impressive!! I knew that the next Gaia data releases would lead to a breakthrough to the field of exoplanets, but I didn't know it would be to that extent 🤯
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
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
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...
It's great.
mathstodon.xyz/@johncarlosb...
November 12, 2025 at 10:19 AM
That's really impressive!! I knew that the next Gaia data releases would lead to a breakthrough to the field of exoplanets, but I didn't know it would be to that extent 🤯
Reposted by Alexis Quintana
it had better make a star cluster when it does 😠
November 10, 2025 at 10:10 AM
it had better make a star cluster when it does 😠
Reposted by Alexis Quintana
Help us to build the Astronomy feeds and The Astrosky Ecosystem! 🔭 ☄️ #astrophotography
We'd especially like to find >1 frontend dev to help work on replacing @bot.astronomy.blue with a simpler web interface, but we have some backend & devops needs to fill too.
More details in the post below ⬇️
We'd especially like to find >1 frontend dev to help work on replacing @bot.astronomy.blue with a simpler web interface, but we have some backend & devops needs to fill too.
More details in the post below ⬇️
We're looking for new developers! - Blog - The Astrosky Ecosystem
We'd like to expand our team to include new devs. We'd especially love to hear from you if you're a frontend developer.
astrosky.eco
November 6, 2025 at 10:31 AM
Help us to build the Astronomy feeds and The Astrosky Ecosystem! 🔭 ☄️ #astrophotography
We'd especially like to find >1 frontend dev to help work on replacing @bot.astronomy.blue with a simpler web interface, but we have some backend & devops needs to fill too.
More details in the post below ⬇️
We'd especially like to find >1 frontend dev to help work on replacing @bot.astronomy.blue with a simpler web interface, but we have some backend & devops needs to fill too.
More details in the post below ⬇️
Reposted by Alexis Quintana
The ageing of host stars can be catastrophic for planets!
Our new research into this planet population shows that the evolution of stars causes giant planets to spiral into their host stars and be destroyed.
Check out the press release below and paper (published in MNRAS today!) for more
Our new research into this planet population shows that the evolution of stars causes giant planets to spiral into their host stars and be destroyed.
Check out the press release below and paper (published in MNRAS today!) for more
🚨New research alert🚨
Ever wondered what might happen to Earth and the other planets in our solar system when the Sun becomes a red giant in 5 billion years? ☀️🔴
Ever wondered what might happen to Earth and the other planets in our solar system when the Sun becomes a red giant in 5 billion years? ☀️🔴
November 5, 2025 at 3:17 PM
The ageing of host stars can be catastrophic for planets!
Our new research into this planet population shows that the evolution of stars causes giant planets to spiral into their host stars and be destroyed.
Check out the press release below and paper (published in MNRAS today!) for more
Our new research into this planet population shows that the evolution of stars causes giant planets to spiral into their host stars and be destroyed.
Check out the press release below and paper (published in MNRAS today!) for more
Reposted by Alexis Quintana
Two views of the rich collections of nebulas and star clusters in the Cygnus and Cepheus areas of the northern Milky Way, in versions with and without labels. Both taken at the end of September at the Southern Alberta Star Party. Tech details in the Alt Text.
November 5, 2025 at 3:43 AM
Two views of the rich collections of nebulas and star clusters in the Cygnus and Cepheus areas of the northern Milky Way, in versions with and without labels. Both taken at the end of September at the Southern Alberta Star Party. Tech details in the Alt Text.
Reposted by Alexis Quintana
Here's a fantastic opportunity for a university student to work on outreach for cutting edge astronomical research: Gaia DR4.
I'd argue that the Gaia Mission should have had a full time person in this role since before 2018, but at least this is something, right?
jobs.esa.int/job/Noordwij...
I'd argue that the Gaia Mission should have had a full time person in this role since before 2018, but at least this is something, right?
jobs.esa.int/job/Noordwij...
Intern in the Science Engagement and Oversight Office, Astrophysics Section
Intern in the Science Engagement and Oversight Office, Astrophysics Section
jobs.esa.int
November 2, 2025 at 5:07 PM
Here's a fantastic opportunity for a university student to work on outreach for cutting edge astronomical research: Gaia DR4.
I'd argue that the Gaia Mission should have had a full time person in this role since before 2018, but at least this is something, right?
jobs.esa.int/job/Noordwij...
I'd argue that the Gaia Mission should have had a full time person in this role since before 2018, but at least this is something, right?
jobs.esa.int/job/Noordwij...
Reposted by Alexis Quintana
🎃The Witch Head Nebula🎃
Image Credit: NASA / STScI Digitized Sky Survey / Noel Carboni
🧪 🔭
Image Credit: NASA / STScI Digitized Sky Survey / Noel Carboni
🧪 🔭
October 30, 2025 at 2:51 PM
🎃The Witch Head Nebula🎃
Image Credit: NASA / STScI Digitized Sky Survey / Noel Carboni
🧪 🔭
Image Credit: NASA / STScI Digitized Sky Survey / Noel Carboni
🧪 🔭
Reposted by Alexis Quintana
Milky Way setting over Versailles Lake
📍Versailles State Park, Versailles IN
📸 Sony A7ii (astro modded) & Sony 20mm F1.8 G
#astrophotography
📍Versailles State Park, Versailles IN
📸 Sony A7ii (astro modded) & Sony 20mm F1.8 G
#astrophotography
October 27, 2025 at 12:12 PM
Milky Way setting over Versailles Lake
📍Versailles State Park, Versailles IN
📸 Sony A7ii (astro modded) & Sony 20mm F1.8 G
#astrophotography
📍Versailles State Park, Versailles IN
📸 Sony A7ii (astro modded) & Sony 20mm F1.8 G
#astrophotography
Reposted by Alexis Quintana
One of the biggest and most publicized disputes in stellar astronomy in recent decades centers on the distance to this star cluster, the Pleiades (the 7 Sisters).
Image credit: my tiny telescope (~4 hours)
#science #astronomy 🔭👩🏾🔬
Image credit: my tiny telescope (~4 hours)
#science #astronomy 🔭👩🏾🔬
October 22, 2025 at 7:54 PM
One of the biggest and most publicized disputes in stellar astronomy in recent decades centers on the distance to this star cluster, the Pleiades (the 7 Sisters).
Image credit: my tiny telescope (~4 hours)
#science #astronomy 🔭👩🏾🔬
Image credit: my tiny telescope (~4 hours)
#science #astronomy 🔭👩🏾🔬
I am currently visiting the Geneva Observatory for the first time to give a seminar tomorrow!
Besides being an exciting opportunity for scientific exchanges, it's always great to learn about the history of astronomical research in specific institutes.
#astronomy
Besides being an exciting opportunity for scientific exchanges, it's always great to learn about the history of astronomical research in specific institutes.
#astronomy
October 22, 2025 at 3:13 PM
I am currently visiting the Geneva Observatory for the first time to give a seminar tomorrow!
Besides being an exciting opportunity for scientific exchanges, it's always great to learn about the history of astronomical research in specific institutes.
#astronomy
Besides being an exciting opportunity for scientific exchanges, it's always great to learn about the history of astronomical research in specific institutes.
#astronomy
Reposted by Alexis Quintana
On the arXiv today, the paper presents how we did 80,000 simulated cluster injection & retrievals to derive the first ever (!!!) full selection function for the open cluster census! 🔭☄️ #galactic
The selection function of the Gaia DR3 open cluster census
Open clusters are among the most useful and widespread tracers of Galactic structure. The completeness of the Galactic open cluster census, however, remains poorly understood. For the first time ever,...
arxiv.org
October 22, 2025 at 12:54 PM
On the arXiv today, the paper presents how we did 80,000 simulated cluster injection & retrievals to derive the first ever (!!!) full selection function for the open cluster census! 🔭☄️ #galactic
Reposted by Alexis Quintana
First Light for 4MOST!
The 4-metre Multi-Object Spectroscopic Telescope (4MOST) has captured its very first spectra!
Video Credit: AIP/R. de Jong, AIP/K. Riebe, AIP/A. Saviauk, CRAL/J.-K. Krogager
The 4-metre Multi-Object Spectroscopic Telescope (4MOST) has captured its very first spectra!
Video Credit: AIP/R. de Jong, AIP/K. Riebe, AIP/A. Saviauk, CRAL/J.-K. Krogager
First Light for 4MOST!
YouTube video by 4-meter Multi-Object Spectroscopic Telescope
youtu.be
October 21, 2025 at 12:00 PM
First Light for 4MOST!
The 4-metre Multi-Object Spectroscopic Telescope (4MOST) has captured its very first spectra!
Video Credit: AIP/R. de Jong, AIP/K. Riebe, AIP/A. Saviauk, CRAL/J.-K. Krogager
The 4-metre Multi-Object Spectroscopic Telescope (4MOST) has captured its very first spectra!
Video Credit: AIP/R. de Jong, AIP/K. Riebe, AIP/A. Saviauk, CRAL/J.-K. Krogager
Reposted by Alexis Quintana
This amazing image by Don Goldman shows the central region of the open cluster NGC 2244 (Caldwell 50), in the heart of the Rosette Nebula (also known as Caldwell 49).
The cluster and nebula lie some 5,000 ly away in Monoceros.
➡️ apod.nasa.gov/apod/ap14031...
🔭 🧪 #science
1/2
The cluster and nebula lie some 5,000 ly away in Monoceros.
➡️ apod.nasa.gov/apod/ap14031...
🔭 🧪 #science
1/2
October 16, 2025 at 2:57 PM
This amazing image by Don Goldman shows the central region of the open cluster NGC 2244 (Caldwell 50), in the heart of the Rosette Nebula (also known as Caldwell 49).
The cluster and nebula lie some 5,000 ly away in Monoceros.
➡️ apod.nasa.gov/apod/ap14031...
🔭 🧪 #science
1/2
The cluster and nebula lie some 5,000 ly away in Monoceros.
➡️ apod.nasa.gov/apod/ap14031...
🔭 🧪 #science
1/2
Reposted by Alexis Quintana
A Tale of Three Stellar Cities!
This is the Orion Nebula, one of the closest stellar nurseries. In it, three different generations of stars live together, a hint to the fact that the stars of a cluster may not form simultaneously 🔭
More: https://www.eso.org/public/images/eso1723a
📷 ESO/G. Beccari
This is the Orion Nebula, one of the closest stellar nurseries. In it, three different generations of stars live together, a hint to the fact that the stars of a cluster may not form simultaneously 🔭
More: https://www.eso.org/public/images/eso1723a
📷 ESO/G. Beccari
October 16, 2025 at 12:02 PM
A Tale of Three Stellar Cities!
This is the Orion Nebula, one of the closest stellar nurseries. In it, three different generations of stars live together, a hint to the fact that the stars of a cluster may not form simultaneously 🔭
More: https://www.eso.org/public/images/eso1723a
📷 ESO/G. Beccari
This is the Orion Nebula, one of the closest stellar nurseries. In it, three different generations of stars live together, a hint to the fact that the stars of a cluster may not form simultaneously 🔭
More: https://www.eso.org/public/images/eso1723a
📷 ESO/G. Beccari
Reposted by Alexis Quintana
Procrastination takes may forms. Tonight as a service to the astronomical community I offer help with your JWST proposal titles.
#JWST 🧪🔭✨
#JWST 🧪🔭✨
October 15, 2025 at 2:56 AM
Procrastination takes may forms. Tonight as a service to the astronomical community I offer help with your JWST proposal titles.
#JWST 🧪🔭✨
#JWST 🧪🔭✨
Reposted by Alexis Quintana
Dans une heure, Salvatore FERRONE soutiendra sa thèse intitulée : « Les courants stellaires pour l’archéologie galactique et cosmique : quand la gravité rencontre la complexité ».
Retransmission sur la chaîne YouTube du LIRA : www.youtube.com/@lira-observ...
lira.obspm.fr/Soutenance-d...
Retransmission sur la chaîne YouTube du LIRA : www.youtube.com/@lira-observ...
lira.obspm.fr/Soutenance-d...
LIRA - Observatoire de Paris-PSL
Le LIRA (Laboratoire d’instrumentation et de recherche en astrophysique) est l’un des trois départements scientifiques de l’Observatoire de Paris-PSL, grand établissement regroupant un quart des…
www.youtube.com
October 13, 2025 at 5:01 AM
Dans une heure, Salvatore FERRONE soutiendra sa thèse intitulée : « Les courants stellaires pour l’archéologie galactique et cosmique : quand la gravité rencontre la complexité ».
Retransmission sur la chaîne YouTube du LIRA : www.youtube.com/@lira-observ...
lira.obspm.fr/Soutenance-d...
Retransmission sur la chaîne YouTube du LIRA : www.youtube.com/@lira-observ...
lira.obspm.fr/Soutenance-d...
Reposted by Alexis Quintana
From my backyard : Summer is going away gracefully, and with it the North America Nebula NGC7000 in the Milky Way plane. I count around 69 000 stars in this #Astrophotography 🔭📷picture!
Can you guess where this is @kat-astro-bot.bsky.social ?
Can you guess where this is @kat-astro-bot.bsky.social ?
October 12, 2025 at 3:03 PM
From my backyard : Summer is going away gracefully, and with it the North America Nebula NGC7000 in the Milky Way plane. I count around 69 000 stars in this #Astrophotography 🔭📷picture!
Can you guess where this is @kat-astro-bot.bsky.social ?
Can you guess where this is @kat-astro-bot.bsky.social ?
Reposted by Alexis Quintana
The John D. and Catherine T. MacArthur Foundation has awarded Kareem El-Badry, assistant professor of astronomy at Caltech, with a 2025 MacArthur Fellowship, an honor that comes with a "no-strings-attached" grant of $800,000.
www.caltech.edu/about/news/k...
www.caltech.edu/about/news/k...
Kareem El-Badry Named a 2025 MacArthur Fellow
Kareem El-Badry Named a 2025 MacArthur Fellow
www.caltech.edu
October 8, 2025 at 5:10 PM
The John D. and Catherine T. MacArthur Foundation has awarded Kareem El-Badry, assistant professor of astronomy at Caltech, with a 2025 MacArthur Fellowship, an honor that comes with a "no-strings-attached" grant of $800,000.
www.caltech.edu/about/news/k...
www.caltech.edu/about/news/k...
Reposted by Alexis Quintana
“When streets became calmer & safer, more people felt comfortable trying a bike commute for the first time. Families began pedaling to the park…Local businesses saw new life…And cycling stopped feeling like a niche activity—it became part of everyday Parisian life.”
Via @momentummag.bsky.social
Via @momentummag.bsky.social
New Study Shows How Paris Pedaled Its Way to a Cycling Revolution
Cycling through central Paris meant weaving between buses and scooters—a bold choice reserved for the fearless few.
momentummag.com
October 8, 2025 at 12:15 PM
“When streets became calmer & safer, more people felt comfortable trying a bike commute for the first time. Families began pedaling to the park…Local businesses saw new life…And cycling stopped feeling like a niche activity—it became part of everyday Parisian life.”
Via @momentummag.bsky.social
Via @momentummag.bsky.social
Reposted by Alexis Quintana
Excellent piece by @briles34.bsky.social on writing in the discipline. It’s depressing that we think that theoretical physics expertise is not just more important but INFINITELY more important than writing to… *writing* PhD dissertations (on any subfield of astro, say). arxiv.org/abs/2510.03493
Surveying the State of Writing Education in Physics and Astronomy
Writing is a critical skill for modern science, enabling collaboration, scientific discourse, public outreach, and more. Accordingly, it is important to consider how physicists and astronomers are tra...
arxiv.org
October 7, 2025 at 10:24 AM
Excellent piece by @briles34.bsky.social on writing in the discipline. It’s depressing that we think that theoretical physics expertise is not just more important but INFINITELY more important than writing to… *writing* PhD dissertations (on any subfield of astro, say). arxiv.org/abs/2510.03493
Reposted by Alexis Quintana
🚀 Voyage du Système solaire aux galaxies, au cœur du LIRA 🌌
Du 3 octobre au 2 novembre 2025, l’Espace culturel Robert-Doisneau accueille l’exposition immersive « Voyage du Système solaire aux galaxies », du mardi au samedi (entrée libre).
lira.obspm.fr/Entre-exposi...
Du 3 octobre au 2 novembre 2025, l’Espace culturel Robert-Doisneau accueille l’exposition immersive « Voyage du Système solaire aux galaxies », du mardi au samedi (entrée libre).
lira.obspm.fr/Entre-exposi...
October 2, 2025 at 6:48 PM
🚀 Voyage du Système solaire aux galaxies, au cœur du LIRA 🌌
Du 3 octobre au 2 novembre 2025, l’Espace culturel Robert-Doisneau accueille l’exposition immersive « Voyage du Système solaire aux galaxies », du mardi au samedi (entrée libre).
lira.obspm.fr/Entre-exposi...
Du 3 octobre au 2 novembre 2025, l’Espace culturel Robert-Doisneau accueille l’exposition immersive « Voyage du Système solaire aux galaxies », du mardi au samedi (entrée libre).
lira.obspm.fr/Entre-exposi...
Reposted by Alexis Quintana
A Sparkling Spray of Stars! ✨
NGC 2264 is located 2600 light-years from Earth in the constellation of Monoceros, the Unicorn 🦄
It includes the sparkling blue baubles of the Christmas Tree star cluster and the Cone Nebula 🔭
Read more: https://www.eso.org/public/images/eso0848a/
📷 ESO
NGC 2264 is located 2600 light-years from Earth in the constellation of Monoceros, the Unicorn 🦄
It includes the sparkling blue baubles of the Christmas Tree star cluster and the Cone Nebula 🔭
Read more: https://www.eso.org/public/images/eso0848a/
📷 ESO
October 2, 2025 at 9:02 AM
A Sparkling Spray of Stars! ✨
NGC 2264 is located 2600 light-years from Earth in the constellation of Monoceros, the Unicorn 🦄
It includes the sparkling blue baubles of the Christmas Tree star cluster and the Cone Nebula 🔭
Read more: https://www.eso.org/public/images/eso0848a/
📷 ESO
NGC 2264 is located 2600 light-years from Earth in the constellation of Monoceros, the Unicorn 🦄
It includes the sparkling blue baubles of the Christmas Tree star cluster and the Cone Nebula 🔭
Read more: https://www.eso.org/public/images/eso0848a/
📷 ESO
Reposted by Alexis Quintana
September 30, 2025 at 8:57 AM
😎
September 26, 2025 at 7:22 AM
😎