ELSA: Euclid Legacy Science Advanced analysis tools

You're right, and this is of course always a consideration, but it's also trivial to create lookalike accounts with similar usernames, so keeping hold of the handle doesn't insulate a person or institution from the risk of impersonation

GLORIOUS beautiful guilded ceiling with frescos of mythological characters, gods flying in the sky with horses, ships, marble, shells, ...

Meanwhile, here's the terribly boring ceiling in the room next to where the ELSA meeting is happening. Why are university rooms and buildings always so dull dull dull?

Screenshot of our dormant Twitter/X account, showing only one post and a pop-up saying "You aren't verified yet".

Screenshot of our Twitter/X account page after deletion, saying this account doesn't exist.

At our f2f meeting today we decided to delete our dormant Twitter/X account, following the excellent example of @ec-euclid.bsky.social. 🧪🔭

ELSA team members, smiling, standing under the ELSA logo

The ELSA @ec-euclid.bsky.social team meeting this week in beautiful Bologna. Amazing things being done with Euclid spectroscopy - watch this space :) 🧪🔭

The two pathways to forming a present-day quiescent spheroid, starting from a star forming disc: field galaxies start with secular bulge formation to make a star-forming spheroid, then internal quenching finished the job, but galaxies in high-density environments start with environmental quenching to make a quiescent disc galaxy, then morphological transformation finishes the job to end again in a quiescent spheroid.

Paper day!! Very nice ELSA @ec-euclid.bsky.social result by Fabrizio Gentile and team, using Euclid's huge dataset to unpick how galaxies' star formation, environment and morphology are connected. Just accepted by A&A 🧪🔭 arxiv.org/abs/2511.02964

Holiday greeting image showing two large galaxies observed by the Euclid space telescope, a small Euclid sketch, and "Joyful holidays and happy DR1-year 2026".

A happy and peaceful holiday season and a prosperous DR1 new year from @ec-euclid.bsky.social in general and the ELSA team in particular 🔭🧪

To find out more about this image: www.euclid-ec.org/happy-holida...

The project will of course continue. Yannick's support team, his deputy, the board and its chair, and our contacts at ESA will continue to work to ensure that the mission continues, as he would certainly have wanted.

Sadly,

Francis Bernadeau (EC Deputy Lead) and Marc Sauvage (Chair EC Board)

3/3

Those of us who have been here the longest know how hard he worked to make Euclid a success. He became its embodiment, working tirelessly to ensure its success; we owe him an immense debt of gratitude, and we will surely have the opportunity to reflect in detail on all that we owe him.

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Au revoir Yannick!

Dear colleagues and friends,

It is with the greatest sadness that we announce the passing of Yannick Mellier, which occurred during the night between Friday and Saturday. His death leaves a huge void within the consortium and our community.

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#astronomy #space #ESA

In Brera (Milan) to present how @elsa-euclid.bsky.social will use AI to study galaxies! @ec-euclid.bsky.social

Sky viewing tool with Euclid's Dark Cloud in the infrared on top of a ground-based visible image.

We followed up #ESAEuclid's near-infrared image of the Dark Cloud LDN 1641 with a comparison to the NIR 2MASS survey, and to a bespoke ground-based image in visible light.

Here's the comparison including a tool to experiment yourself:

www.euclid-ec.org/clouds-darkn...

#ESA #space #science 🔭

YouTube video by Euclid Consortium Infrared vs Optical: Euclid reveals what lies within and behind the Dark Cloud

Beautiful comparison of @ec-euclid.bsky.social's infrared view of an interstellar dark cloud, compared to what we see in optical light 🧪🔭 www.youtube.com/watch?v=MlmQ...

wow....

The solar flare that caused aurora here on Earth a few days ago, also caused a blizzard of particle impacts on @ec-euclid.bsky.social's detectors. Very nice explainer by @james4cet.bsky.social www.euclid-ec.org/here-comes-t... 🧪🔭

Anticipating Geomagnetic Storms: Reflections at the Halfway Point (Part 2) Keen AI and National Grid secure Ofgem funding to develop FoSMO, the UK’s first shared AI vision model to transform electricity network asset management.

Blog post by @ec-euclid.bsky.social PhD student Ruby Pearce-Casey from her #DISCnet industry placement with #KeenAI, deploing her AI skills to new areas. Earlier, Ruby made a breakthrough in finding strong gravitational lenses in Euclid imaging using machine learning keen-ai.com/blog/anticip... 🧪🔭

Anticipating Geomagnetic Storms: Reflections at the Halfway Point (Part 2) Keen AI and National Grid secure Ofgem funding to develop FoSMO, the UK’s first shared AI vision model to transform electricity network asset management.

Very nice blog post by my grad student Ruby Pearce-Casey (who's done excellent @ec-euclid.bsky.social work on finding strong gravitational lenses), from her #DISCnet industry placement with #KeenAI 🧪🔭 keen-ai.com/blog/anticip...

Let me tell you, our officially-not-an-X-ray-telescope #ESAEuclid did notice this flare. Very much so. A gazillion cosmic ray hits, plus a shadow of hardware where the instruments aren't fully X-ray shielded.

I mean this was the 39th (?) strongest flare in 30 years.

Whoa. The scale of this thing.

That blast wave radiating away from the flare location is impressive. Esp. when you think about the size of the Earth in comparison.

It’s so very near that we live so close to a star and can watch its behaviour and activity.

A star and it’s just right there!

"Euclid's ability to cover such a large area of sky makes it a marvellous place to find rare objects that often could not be discovered in any other way. Euclid also doesn't just take images; its spectroscopic instrument also splits light up like a rainbow to diagnose how redshifted (how far away) each galaxy is and the conditions inside each galaxy. In this paper [Vergani et al] we used Euclid's spectroscopic instrument to unveil a population of rare galaxies with stronger ionizing radiation inside them, perhaps caused by a curious, unusual history of star formation that's assembling the stellar masses of galaxies. Unpicking this will be the subject of a lot of future research, and this is just the tip of the iceberg of the rare object discoveries awaiting us with Euclid."

Many other @ec-euclid.bsky.social papers being released this week, including by Daniela Vergani and team on discoveries of galaxies with unusual emission lines - here's an explainer by @stephenserjeant.bsky.social 🧪🔭

Many new @ec-euclid.bsky.social papers have just been released too, including this beautiful morphological tuning fork of galaxies 🔭🧪 This page is interactive - have a play! www.euclid-ec.org/euclid-morph...

Image taken by the Euclid space telescope of stars on a dark background, with wispy clumps in the foreground that comprise an infrared dark cloud, made visible via Euclid's infrared camera.

Some marvellous @ec-euclid.bsky.social press releases just out! A beautiful image of a shimmering infrared dark cloud observed with Euclid www.esa.int/ESA_Multimed...

Rather lovely blog marking the second anniversary of the launch of @ec-euclid.bsky.social, by @knudjahnke.bsky.social www.euclid-ec.org/second-anniv... 🔭🧪

Candidate Dark Galaxy-2: Validation and Analysis of an Almost Dark Galaxy in the Perseus Cluster Candidate Dark Galaxy-2 (CDG-2) is a potential dark galaxy consisting of four globular clusters (GCs) in the Perseus cluster, first identified in Li et al. (2025) through a sophisticated statistical m...

arXiv version of the paper: arxiv.org/abs/2506.15644

Candidate Dark Galaxy-2: U of T researchers shine new light on the universe’s darkest realms.

"Almost dark galaxy" discovered with the help of the @ec-euclid.bsky.social archive - press release in English 🧪🔭 www.statistics.utoronto.ca/news/candida...

Candidate Dark Galaxy-2: Validation and Analysis of an Almost Dark Galaxy in the Perseus Cluster - IOPscience Candidate Dark Galaxy-2: Validation and Analysis of an Almost Dark Galaxy in the Perseus Cluster, Li, Dayi (David), Liu, Qing, Eadie, Gwendolyn M., Abraham, Roberto G., Marleau, Francine R., Harris, William E., van Dokkum, Pieter, Romanowsky, Aaron J., Danieli, Shany, Brown, Patrick E., Stringer, Alex

Here's a link to the academic paper (free, open access): iopscience.iop.org/article/10.3...

„Dunkle Galaxie“ im Perseushaufen entdeckt Ein internationales Forschungsteam unter Beteiligung von Francine Marleau von der Universität Innsbruck hat eine nahezu unsichtbare Galaxie im Perseus-Galaxienhaufen identifiziert. Entdeckt wurde die ...

New Euclid archive result: discovery of an "almost dark galaxy" with four globular clusters. Wonderful to see the community make great use of the @ec-euclid.bsky.social archive! Press release (in German): 🔭🧪 www.uibk.ac.at/de/newsroom/...

Thank you :)

YouTube video by OpenLearn from The Open University Black Holes - 60 Second Adventures in Astronomy (12/14)

Black Holes www.youtube.com/watch?v=5p3k...

YouTube video by OpenLearn from The Open University Special Relativity - 60 Second Adventures in Astronomy (10/14)

Special Relativity www.youtube.com/watch?v=mU04...

YouTube video by OpenLearn from The Open University Dark Energy - 60 Second Adventures in Astronomy (9/14)

Dark Energy (featuring the @ec-euclid.bsky.social telescope) www.youtube.com/watch?v=7Yc2...