Dr. Heloise Stevance

Bitterly disappointing to see the Astronomer Royal—who should be advocating for the importance of astronomy and its contributions to society—imposing the greatest cuts to astronomy research in a generation

Glad to see that the Astronomer Royal for Scotland is fulfilling her role properly 🏴󠁧󠁢󠁳󠁣󠁴󠁿

☄️🔭

Illustrated graphic with the boot-shaped Rubin Observatory atop its site on Cerro Pachón beneath a sparkling night sky and the glowing band of the Milky Way stretching from lower left to upper right. Sprinkled throughout are many "Data alert!" popups, labeled with icons that represent supernovae, asteroids, hungry black holes, and more.

A 3-by-4 grid of grayscale astronomical images zoomed in on single objects. From left to right, the columns are labeled Template, New image, and difference. From top to bottom, the rows are labeled supernova, variable star, active galactic nucleus, and solar system object.

The largest spot-the-difference effort EVER has begun!🚨

On the night of Feb 24, NSF–DOE Rubin Observatory officially released its first ~800,000 public alerts of detected changes in the night sky!🔍

A new era of discovery is here✨ 🔭🧪☄️

🔗: rubinobservatory.org/news/first-a...

A 3-by-5 grid of grayscale astronomical images zoomed in on single objects, specifically active galactic nuclei. From left to right, the columns are labeled Template, New image, and difference. From top to bottom, the rows are labeled active galactic nucleus 1-5.

A 3-by-5 grid of grayscale astronomical images zoomed in on single objects, specifically solar system objects. From left to right, the columns are labeled Template, New image, and difference. From top to bottom, the rows are labeled solar system object 1-5.

A 3-by-5 grid of grayscale astronomical images zoomed in on single objects, specifically supernovae. From left to right, the columns are labeled Template, New image, and difference. From top to bottom, the rows are labeled supernova 1-5.

A 3-by-5 grid of grayscale astronomical images zoomed in on single objects, specifically variable stars. From left to right, the columns are labeled Template, New image, and difference. From top to bottom, the rows are labeled variable star 1-5.

These first alerts use early, pre-survey observations while Rubin finishes preparations to begin its decade-long survey. 🔭🧪☄️

This is just the start for a system that is expected to produce up to ~7 million of these alerts per night! ✨

🔗: rubinobservatory.org/news/first-a...

Dr Héloïse Stevence is a Schmidt AI in Science Fellow at the University of Oxford.

We catch up with Héloïse Stevence @sydonahi.bsky.social to talk astronomy and machine learning – and discover how many Rubin images this Schmidt AI in Science Fellow can classify per minute with the human eye. Read our latest In the Spotlight interview: www.lsst.ac.uk/news/2026-02... 🔭

🚀 Astro-COLIBRI v2.26.0 is now available! We are excited to announce the release of Astro-COLIBRI v2.26.0 (January 28, 2026). This update brings again significant improvements to the user interface, powerful new science tools for observation ...

🚀 Astro-COLIBRI v2.26.0 is live! ☄️

This update brings cool new tools and better accessibility:
🌍 Multi-language support (EN, DE, FR, ES, IT)
👤 #Google Login
🔭 Observation planning for #Fermi & #IceCube
🌌 New Host-Galaxy Cross Matching tool

Read the full changelog here: tinyurl.com/ver2-26

Expert Comment: Computers can help us to do science, but they can’t Dr Heloise Stevance, Schmidt AI in Science Fellow in Oxford University’s Physics Department, is a computational astrophysicist developing intelligent recommendation systems for sky surveys. In this

A couple of weeks ago I was asked to speak at the AI and Ethics conference organised at Oxford - my talk has now been put online and summarised in a written piece you can read for free!

After the shenanigans at NeurIPS, scientific rigour is more important than ever

www.ox.ac.uk/news/2026-01...

Diagram showing changes detected in one Rubin image including supernovae, variable stars, active galactic nuclei, and solar system objects. In total, each Rubin will contain up to 10,000 changes, ~70% of which will be variable stars.

One Rubin image = up to ~10,000 alerts! 🌌🔭

From supernovae to asteroids, comets, and more, Rubin will capture the Universe in action every night. ☄️✨

See what kinds of events Rubin will alert us to: https://rubinobservatory.org/explore/how-rubin-works/alerts

Héloïse Stevance, l’astrophysicienne qui sonde l’Univers grâce à l’IA La jeune Française a créé une intelligence artificielle qui filtre, parmi une infinité de données, les signaux cosmiques les plus prometteurs.

The article in French can be read at this link if anyone feels like trying out their GCSE french ahaha www.lepoint.fr/sciences-nat...

VRA paper for the curious ❤️

[2506.09778] The ATLAS Virtual Research Assistant share.google/dNZYpHAVPQy4...

Le Point on Instagram: "🔭Chaque nuit, les télescopes du réseau ATLAS scrutent le ciel à la recherche d'astéroïdes menaçants, d'explosions d'étoiles et d'autres événements cosmiques éphémères. ⏰Chaqu... 47 likes, 0 comments - lepointfr on December 6, 2025: "🔭Chaque nuit, les télescopes du réseau ATLAS scrutent le ciel à la recherche d'astéroïdes menaçants, d'explosions d'étoiles et d'autres événement...

This week my work on the Virtual Research Assistant that helps our teams find extra galactic transients appeared in a very big French news Magazine (glossy paper and all).

Now I'm making my VRAs for LSST 👀. Watch this space in 2026 for more coll science #astrosci

www.instagram.com/p/DR6k7owDnt...

A bright white object glowing with green tones against a dark, starry space backdrop. The text "3I/ATLAS Facts, not fiction" appears on the image.

The interstellar visitor 3I/ATLAS ☄️ cruising through our Solar System is no alien spaceship and won't hit Earth.

Still, the buzz around it is far from unfounded 🤩

Discover why with #ChasingStarlight: https://www.youtube.com/watch?v=YtiqLxfSiVI

🔭 🧪

Release Notes v2.25.0: Major Mobile UX Update, RAPAS Photometry & LAST Integration Dear Astro-COLIBRI community, We are excited to announce the release of version 2.25.0! This update brings a significant overhaul to the mobile user interface to make navigation smoother during your ...

We've just released a massive update to Astro-COLIBRI! 🔭☄️🧪⚛️
Version 2.25.0 features a completely redesigned mobile experience (yes, you can finally swipe between screens!) and adds powerful new data sources like the RAPAS network and LAST Observatory.

More details in our forum: tinyurl.com/ACv2-25

The Moon-forming impactor Theia originated from the inner Solar System The Moon formed from a giant impact of a planetary body, called Theia, with proto-Earth. It is unknown whether Theia formed in the inner or outer Solar System. We measured iron isotopes in lunar sampl...

A giant impact between proto-Earth and a planet called Theia produced the Moon. Hopp et al. use isotopic measurements of lunar samples and cosmochemical modelling to show that Theia formed in the inner Solar System, probably closer to the Sun than Earth. ☄️ #planetsci
www.science.org/doi/10.1126/...

When you feel vulnerable, whatever the reason, try to stop your brain focusing on the things you lack, and analyse the things you can bring and share with the group. Sometimes all we have to bring to the table is enthusiasm and time, but that's already a lot.

Happy Science!

And this analysis will depend on the crowd you're in and the theme of interest. But for example it can be that you have a closer link to the day-to-day challenges of the science or the method because you ACTUALLY DO IT (professor delegate).

Maybe you know a novel method, maybe you have QUESTIONS!

When you're the youngest in the room, there will be things you have less of: titles, number of papers, research achievements. It's when we focus on these that we talk ourselves down or over compensate.

So we need to focus on what we have MORE of:

Don't talk yourself down, but don't over-compensate.

When we feel "small" humans have one of two common ways of coping: Some will talk themselves down in an attempt to raise sympathy from the crowd; some will exaggerate their confidence or achievement to feel less small.

There's another way...

Me standing behind a podium (left hand side) on a large stage (15 meters across?) with a very large wall-screen displaying my title slide "Virtual Research Assistants for Sky Surveys; Intelligence is in the Design not in the Models"

Last week I had the honour to speak at the 5th Innovation Forum for Intelligent Computing at Zheijang Lab, and share my voice on a panel with experts with a lot more seniority.

Here are some tips for early career researchers for when you're the youngest in the room and feeling small

🧪🔭

Cannot generate simple excel files on pro version Question So I have used ChatGPT pro for a while now and recently I have been facing an issue while trying to collate data from pdfs and put it in an excel sheet where in my chat it keeps asking me questions when it finally gets down to generating an excel sheet it never gives me the me the link to download the file. After multiple attempts when it does give me a lin k to download the excel file I rec an error which says file not found. Starting to grow frustrated with this now. Look forward to any suggestions to tackle this #problem

This person is paying OpenAI two hundred dollars a month to have a chatbot gaslight them about making an excel spreadsheet

We are pleased to announce that the Astrophysics Centre for Multimessenger Studies in Europe (ACME) EU-funded project has officially launched its online platform for virtual access to multi-messenger expertise. 🔭🧪⚛️☄️

support.acme-astro.eu

Details in the thread below and on: www.acme-astro.eu

Ice Crystals in the atmosphere!

Witness to the Hellfire of Genocide I didn’t write this to make you cry.Not for you to tell me: “Poor you.”I write this so I can hang these words around your neck—to make you bear the responsibility of my perspective,the responsibility ...

Today is the release day of Gazan physics student Wasim Said's memoir of life under the genocide. 🧪

You should grab a copy. #BookSky

1804books.com/products/wit...

A high fraction of close massive binary stars at low metallicity - Nature Astronomy The analysis of radial velocity variations of O-type stars in the Small Magellanic Cloud reveals a large fraction of close binaries, suggesting that binary physics also plays a prominent role in the l...

"no evidence supporting a statistically significant trend of [O star] multiplicity properties with metallicity" still high (~70%) in the SMC - interesting! 🔭🧪 #AstroSci #extragalactic

How long do we give the techno-bros to start weaponising DEI by saying their fave AI is conscious and has feelings and saying otherwise is "dehumanizing" and cruel?

That’s a much better title yeah

AI tool developed at Oxford helps astronomers find supernovae in a A new AI-powered tool has reduced astronomers’ workload by 85% - filtering through thousands of data alerts to identify the few genuine signals caused by supernovae (powerful explosions from dying

My preferred title "Bot does Astronomers' Cosmic Laundry"

But I guess it didn't sound serious enough.

Fun fact the tool still works even though we added a whole new telescope in the stream this summer and without retraining 🤣🫶

www.ox.ac.uk/news/2025-09...

Design.

The hardest part of applied ML is asking the right question and choosing the right metrics.

Once you've done that you can pick the right model and in science it's often not the biggest newest thing!

ML is not a dick measuring contest but I'll leave this for another rant later today 💅

"AI-powered" is obviously a marketing term.

My models use a nifty little trick called Histogram Based Gradient Boosted Decision trees.

TL;DR it approximates complex probability distributions by adding loads of small functions (here trees).

Why is it smart if it's so simple?

1/2 #AstroSci

AI tool helps astronomers find supernovae in a sky full of noise A new AI-powered tool has reduced astronomers' workload by 85%—filtering through thousands of data alerts to identify the few genuine signals caused by supernovae (powerful explosions from dying stars...

Nice work by @sydonahi.bsky.social
phys.org/news/2025-09...

Diagram showing 3 cartoon "monsters" all with straight tails to illustrate that if you only have the tail you can't do classification properly.

Reminder that you can take your science seriously without taking yourself too seriously.

#AstroSci 🧪