iiinova — where your digital self keeps evolving

Reposted by Romain Meyer

Nature @nature.com · 06/10/2026

BREAKING: The Nobel Prize in Physics has been awarded to Francis Halzen “for decisive contributions to the IceCube Neutrino Observatory and the discovery of high-energy neutrinos of astrophysical origin.” More to follow.

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Taylor Smith @taylorjsmith.bsky.social · 01/10/2026

I’ve known about this for a couple of weeks, but now I can share: as of today, arXiv is rate-limiting submissions to two per month. And as a mod, I have to admit this is a necessary move (at least temporarily). blog.arxiv.org/2026/10/01/u...

blog.arxiv.org

Fair Moderation, Equitable Access, and AI: arXiv’s Updated Rate Limit Policy

arXiv, and the scientific community at large, are facing a watershed moment. Scholarly publishing is currently changing at a rapid pace, and we are seeing a…

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Reposted by Romain Meyer

Space Telescope Science Institute @stsci.edu · 15/09/2026

#NASARoman activated the Wide Field Instrument—a 300-megapixel infrared camera that will allow it to explore wide swaths of the cosmos quickly. This test image captures the very first photons of starlight to reach the instrument—taken as an initial performance assessment: go.nasa.gov/4rg4qEc

$At the top, a grid of 21 panels shows a series of blue images with tiny neon green and yellow circles. A larger image highlights a section of the grid with circular patterns, and an inset presents a detailed star-like diffraction pattern. The colors consist of blue, green, and yellow.$

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ESO @eso.org · 04/09/2026

Heard the news? The new VLT instrument MOONS, built by a consortium led by the UK Astronomy Technology Centre, has made its first observations 🙌 Get the gist with this video by the UK Science and Technology Facilities Council: www.youtube.com/watch?v=LlAdjG7exug 🔭 🧪 #instrumentation 1/2

youtube.com

MOONS captures its first light, no telescope has ever seen this before

MOONS has captured its first light, almost one thousand objects in ...

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Romain Meyer @astrorameyer.bsky.social · 03/09/2026

I am delighted to say that I have been awarded an #ERC Starting Grant!! For the next 5 years I will lead a group as Asst Prof at the Dept of Astronomy at the University of Geneva #UNIGE. We will use JWST&VLT observations to provide a 3D view of reionisation and its sources, and prepare for SKA/ELT!

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Romain Meyer @astrorameyer.bsky.social · 29/05/2026

to the observatory for sure, but to the proposers I'm not quite sure this is allowed given the new rules and guidelines around constructive reviews that ALMA has provided for Cycle 13..

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Romain Meyer @astrorameyer.bsky.social · 29/05/2026

I have to review ALMA proposals and clearly one is LLM-generated. I cannot flag it or fail it just because of that, but it's unsurprisingly very bad. I'm very annoyed that someone is fine generating crap and wasting the time of *10* peer reviewers (prohibited to use LLMs for this). Stop it!!

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Romain Meyer @astrorameyer.bsky.social · 21/04/2026

The new ALMA online observing tool for submitting proposals is functioning as expected: crashing under lots of requests before the deadline (and it's only 2 days away!!). I guess there was no way to expect this high number of requests, right...? 🤦‍♂️

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Romain Meyer @astrorameyer.bsky.social · 05/04/2026

New personal best is "only" z~10.6 and z~10.3 for now... Waiting for two more sources getting to the ground and through the pipeline. Fingers crossed

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Romain Meyer @astrorameyer.bsky.social · 02/04/2026

Chances are that I will break my personal redshift record (z~9) tonight as 5 targets from my #JWST programme 7208 are observed.. Nothing too crazy but potentially z~12 so that would be nice! Exciting 😃

Screenshot of scheduled targets for JWST programme 7208. 5 targets are scheduled in the evening of April 2, with 3 more on April 3-5.

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Romain Meyer @astrorameyer.bsky.social · 17/03/2026

Last Friday I learned that my #JWSTCycle5 proposal was approved: 107 hours to do the first tomographic map of the IGM at the end of Reionisation - quite ambitious! 🥳 We will also collect >2000 PRISM spectra as fillers in COSMOS for legacy science. #extragalactic www.stsci.edu/jwst/science...

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Romain Meyer @astrorameyer.bsky.social · 09/03/2026

So... #JWST Cycle 5 results will be announced this week, right? ... Right? I can't take another week of waiting.

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Reposted by Romain Meyer

Ava Polzin @avapolzin.bsky.social · 08/03/2026

Happy International Women's Day! Perfect time for me to (re)share our white paper on increasing the retention of women in professional astrophysics (really full of suggestions that broaden participation in academic science in general). arxiv.org/abs/2512.24465 🧪🔭☄️👩‍🔬

Cover of "Picture an Astronomer: Best Practices for Retaining Talent in Astrophysics", which features an illustration of a 19-year-old Vera Rubin looking through a telescope over a backdrop of a first light image of spiral galaxies from the Rubin Observatory.

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Romain Meyer @astrorameyer.bsky.social · 20/02/2026

it seems plausible that today we might get invitations to interviews (or not) for ERC Starting grants in the PE panels and I have rarely been so stressed..

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Reposted by Romain Meyer

Mike Boylan-Kolchin @mbkplus.bsky.social · 12/02/2026

David Hogg has written a white paper on doing astrophysics in the age of LLMs. It looks to be thought-provoking. My initial reaction is that either LLMs will destroy the field or they will force a reckoning with and re-imagining of the current system that often prioritizes output over quality. 🧪

arxiv.org

Why do we do astrophysics?

At time of writing, large language models (LLMs) are beginning to obtain the ability to design, execute, write up, and referee scientific projects on the data-science side of astrophysics. What implic...

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Romain Meyer @astrorameyer.bsky.social · 03/02/2026

The goal of the proposal is to target Lyman-alpha in z>5 galaxies pre-selected with JWST grism (Hb or Ha) to map the 3D progress of reionisation in the iconic COSMOS field. The COSMOS-3D team also got Subaru/PFS and Keck/MOSFIRE time for this - we are ~1 year away from some really cool stuff! 🔭

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Romain Meyer @astrorameyer.bsky.social · 03/02/2026

Yesterday I got news that my 84 hours proposal on VLT/FORS2 was approved! I've been on a high since then. 🤩 Beating the 11.5 oversubscription on UT1 is very satisfying..

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Romain Meyer @astrorameyer.bsky.social · 20/01/2026

they use dark gaps/pixels measurements (Davies+2026, Zhu+2022) that only provide (by design) upper limits (but at higher z) than LyA transmission. LyA opacity constraints on X_HI are really tight up to z<5.4 and then lower limits up to z~6 (Bosman+22, Fig. 14) - but not used here for some reason??

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Romain Meyer @astrorameyer.bsky.social · 20/01/2026

BUT the EW(LyA) conversion to x_hi from galaxies is very model-dependent, probably the most difficult probe of x_HI. Mostly I'm surprised that they (and other) ignore the Lyman-alpha forest constraints from quasars at z<6 - super robust and already in tension with some tanh et al. x_HI histories.

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Romain Meyer @astrorameyer.bsky.social · 20/01/2026

Generally I have always thought that using galaxy/quasar observations of x_HI as a prior to whatever reionisation histories used in the fitting of CMB data is a good thing. Using a tanh or else parametrisation of x_HI(z) when we have relatively good constraints at z<7.5 seems a waste

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Reposted by Romain Meyer

Bibiana Prinoth @handle.invalid · 17/12/2025

The application for the ESO Summer Research Programme 2026 has just opened! It‘s a six week programme in Garching close to Munich where pre-Ph.D students can work on a hands-on project. Working at @eso.org is a fabulous experience, so please help me spread the word ✨ 🔗 eso.org/sci/meetings...

eso.org

ESO - SummerResearch2026

ESO is the European Organisation for Astronomical Research in the Southern Hemisphere. It operates the La Silla Paranal Observatory in Chile and has its headquarters in Garching, near Munich, Germany.

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Romain Meyer @astrorameyer.bsky.social · 04/12/2025

Yes or your supervisor does this for you. Sadly I hear the opposite is happening! Some editors are desperate and some relatively junior PhD students in my dept have been asked (and provided) reports..

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Romain Meyer @astrorameyer.bsky.social · 04/12/2025

ultimately this is about balancing your karma. I have anecdotal evidence of people in the field admitting they just flat out refuse any refereeing request because they are busy - but will then happily submit 2+ papers this year.

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Romain Meyer @astrorameyer.bsky.social · 04/12/2025

I mean, ok, you need to put some thinking in managing the fiat money. But unlike babysitting, everyone publishes regularly. This is equivalent to double-anonymous peer-review that is being implemented by ALMA/ESO/JWST to manage the surge in observing proposals but with a time-delay component

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Reposted by Romain Meyer

Jorryt Matthee @jorryt.bsky.social · 04/12/2025

Happy to share my introductory review article "JWST provides a new view of cosmic dawn: latest developments in studies of early galaxies" has now been published in Contemporary Physics! www.tandfonline.com/doi/full/10.... arxiv.org/abs/2511.04843

tandfonline.com

JWST provides a new view of cosmic dawn: latest developments in studies of early galaxies

Studies of the distant Universe are providing key insights into our understanding of the formation of galaxies. The advent of the James Webb Space Telescope (JWST) has significantly enhanced our ob...

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Romain Meyer @astrorameyer.bsky.social · 04/12/2025

how I wished we'd get paid! but apparently this is a non-starter...

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Romain Meyer @astrorameyer.bsky.social · 04/12/2025

This way the burden of refereeing is borne by those submitting, which sounds fair? Bonus: review tokens should be shareable. You can trade tokens with colleagues, help busy students, or reward underappreciated committee/service work with tokens because they map to actual working time! #academia

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Romain Meyer @astrorameyer.bsky.social · 04/12/2025

Finding referees seems to be increasingly difficult for journals, but people in my field submit *multiple* papers per year. Hot take: I propose a token currency where submitting a paper costs a token, and one review earns you one. You cannot submit yet another paper if your deficit is >N. #academia

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Romain Meyer @astrorameyer.bsky.social · 18/11/2025

a bit sceptical of these claims when the galaxies SED are only fitted with exponentially declining star-formation histories. At z~6 this is quite a bold claim that no other SFH are plausible/preferrable... most likely exp-declining SFH end up producing higher masses

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Romain Meyer @astrorameyer.bsky.social · 07/11/2025

A delayed announcement - the 2nd chapter of the Saas-Fee 2025 Lectures is now out on arXiv. Marta Volonteri did a fantastic job reviewing how we model the formation and growth of early massive black holes, and how JWST results are helping: arxiv.org/abs/2510.04599 (another 2 chapters will follow)

arxiv.org

Theoretical Modelling of Early Massive Black Holes

These notes review theoretical models of massive black hole formation, growth and observables. They start with a brief summary of basic properties of massive black hole properties. The current view on...

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Cédric Brun @cedricbrun.bsky.social · 31/10/2025

Quand notre ministre de tutelle nous insulte devant la représentation nationale. "Bande de nuls" "complètement à la ramasse". Nous reprocher des taux de réussite faible à Horizon Europe et ERC, quand manquent les moyens pour assurer nos missions de service public. Surtout changez rien!👌

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Reposted by Romain Meyer

Paul Byrne @theplanetaryguy.com · 28/10/2025

Another STUNNING image from JWST, this time of the Red Spider Nebula—the vast, wispy, gaseous remains of a now-dead star, the white dwarf core still glowing in the centre.

A series of wispy, blue strands emanate from the centre of the image, which is glowing orangey–red with a little pink. The background is FESTOONED with stars, all set against a black backdrop.

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Romain Meyer @astrorameyer.bsky.social · 24/10/2025

I can't assess whether the number and ionising output of the PopIII.1 / SMBH progenitors would be enough.. But I note that in the z=20 Flash model, the ionised fraction is 10% at z=14, which we could soon measure with Lyman-alpha/damping wings with JWST. The z=25 scenario is much harder to rule out!

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Romain Meyer @astrorameyer.bsky.social · 21/10/2025

In short, there is now a patch of the sky the size of the full moon for which we know the 3D structure of all luminous* galaxies at a time when the Universe was basically a toddler!

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Romain Meyer @astrorameyer.bsky.social · 21/10/2025

Usually confirming distant galaxies is hard and can only be done in very small fields. This field (COSMOS) is roughly the size of the *full moon* - pretty big by extragalactic standard. Also notable here is the use of a specific JWST instrument to confirm *all* galaxies in one go in that field.

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Romain Meyer @astrorameyer.bsky.social · 21/10/2025

Thanks! Here would be a jargon-free version: Thanks to #JWST we have precisely mapped the location of 237 galaxies so distant we see them as they are 0.5-0.8 Billion years after the Big Bang (we are a +13.7 billion years - their light travelled 13 billion years to reach us!).

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Romain Meyer @astrorameyer.bsky.social · 17/10/2025

Obviously this is a short paper showing the detections and the LF, but lots of work on environments and reionisation will follow from the COSMOS-3D collaboration. Considering the data was taken in May 2025 (mostly), this is not too bad... You can check the full paper here: arxiv.org/abs/2510.11373

arxiv.org

JWST COSMOS-3D: Spectroscopic Census and Luminosity Function of [O III] Emitters at 6.75<z<9.05 in COSMOS

We present a spectroscopically-selected [OIII]+Hb emitters catalogue at 6.75<z<9.05 and the resulting [OIII] 5008 ÅLuminosity Function (LF) in the COSMOS field. We leverage the 0.3 deg$^{2}$ covered t...

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Romain Meyer @astrorameyer.bsky.social · 17/10/2025

The paper focuses on the OIII luminosity function and the fact that with 0.3 degree squares, we can finally beat down cosmic variance (but only to 15% relative uncertainty). You need wide-area surveys to sample all environments - something difficult with JWST. Lot of structure even in COSMOS 👇

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Romain Meyer @astrorameyer.bsky.social · 17/10/2025

You probably missed it because of some deadline but on Tuesday we published the results of an [OIII] emitters search in the COMOS(-3D) field using slitlless spectroscopy. That's *237* 6.7<z<9 uniformly-selected spec-z galaxies over 0.3 degrees square. See the piled 2D plots below, that's a lot!

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Sarah Kendrew @sarahkendrew.bsky.social · 27/08/2025

On astro-ph today, a nice set of lecture notes from Richard Ellis (UCL) on Galaxies and Black Holes in the first Billion years - with special focus on new results from JWST. It also illustrates why MIRI is essential for accurately estimating galaxies' stellar masses ✨ arxiv.org/abs/2508.16948 🔭

arxiv.org

Galaxies and Black Holes in the First Billion Years

I present written notes from three lectures given at the 54th Saas-Fee Advanced Course of the Swiss Society of Astrophysics and Astronomy in January 2025 entitled "Galaxies and Black Holes in the Firs...

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Romain Meyer @astrorameyer.bsky.social · 26/08/2025

This is an excellent intro read for students and other interested folks, especially including discussing the pre-JWST era and the historical perspective in extragalactic astronomy over 2-5 decades. #astronomy #extragalactic #jwst

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Romain Meyer @astrorameyer.bsky.social · 26/08/2025

In January we held the very successful Saas-Fee Lectures on the revolution JWST is unleashing in high-redshift studies, covering BH and galaxies, observations and theory. The first set of lecture notes by Richard Ellis is now available on arXiv (3 more will follow): arxiv.org/abs/2508.16948 .

arxiv.org

Galaxies and Black Holes in the First Billion Years

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Cosmic Dawn Center @cosmicdawncenter.bsky.social · 13/08/2025

We are excited to make the first official announcement for the 𝗖𝗵𝗮𝗿𝘁𝗶𝗻𝗴 𝗖𝗼𝘀𝗺𝗶𝗰 𝗗𝗮𝘄𝗻 conference in Copenhagen in 12–17 April next year 🤩 cosmicdawn.dk/meetings-and...

cosmicdawn.dk

Charting Cosmic Dawn in Copenhagen 2026 - Cosmic Dawn Center

An overview of the 2026 workshop "Charting Cosmic Dawn in Copenhagen."

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Rychard Bouwens @introspectrych.bsky.social · 07/08/2025

Extremely excited to share that the PHOENIX team, led by PhD student Sander Schouws in Leiden, has been awarded 113 hours of ALMA time in Cycle 12—along with JWST MIRI spectroscopy! We’ll be targeting [OIII]88 and the dust continuum in 15 of the brightest spectroscopically confirmed galaxies 1/n

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John F Wu @jwuphysics.bsky.social · 16/07/2025

Whoa. Three Little Red Dots have now been found in SDSS! arxiv.org/abs/2507.10659 But due to their compact morphology and bizarre colors, they are originally selected as *quasar candidates*, not galaxies! In any event, LRDs are not unique to the high-z universe. #astrosci

arxiv.org

The Discovery of Little Red Dots in the Local Universe: Signatures of Cool Gas Envelopes

JWST observations have revealed a population of high-redshift "little red dots" (LRDs) that challenge conventional AGN models. We report the discovery of three local LRDs at $z = 0.1-0.2$, initially s...

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Romain Meyer @astrorameyer.bsky.social · 08/07/2025

and once again, the JWST call for proposal is in exact sync with the ERC StG deadline.. 🥲

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