Author | Lightnews

Denis Erkal @derkal.bsky.social · 1d

That sounds like fun! Nice demonstration!

Reposted by Denis Erkal

NSF–DOE Rubin Observatory @vrubinobs.bsky.social · 12d

We come with receipts🧾

Tidal tails are cosmic “receipts” of galactic drama, showing who collided with whom. Rubin's camera is sharp enough to catch wind of even the faintest intergalactic tea.

No need to worry about "pics or it didn't happen" with Rubin keeping a close eye 😎 🔭🧪

A sprawling field of galaxies fills the deep black of space, dotted with glowing stars and colorful smudges of light. Near the top, a smooth golden elliptical galaxy glows like polished stone, linked by delicate, taffy-like streams of stars to nearby galaxies below—evidence of ancient cosmic collisions.

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Denis Erkal @derkal.bsky.social · 26d

Looking forward to it. Just bought a signed edition in the UK! Loved the Dandelion Dynasty!

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Reposted by Denis Erkal

Marcel S. Pawlowski @8minutesold.bsky.social · 28d

Paper day! My PhD student Mariana Júlio, with @readdark.bsky.social, @pengfeili.bsky.social and others, studies the internal dynamics of dwarf galaxies and finds they don't agree with the Radial Acceleration Relation, challenging the dark matter alternative MOND.

arxiv.org/abs/2510.06905

🔭☄️🧪
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The radial acceleration relation at the EDGE of galaxy formation: testing its universality in low-mass dwarf galaxies

A tight correlation between the baryonic and observed acceleration of galaxies has been reported over a wide range of mass ($10^8 < M_{\rm bar}/{\rm M}_\odot < 10^{11}$) - the Radial Acceleration Rela...

arxiv.org

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Denis Erkal @derkal.bsky.social · Sep 30

4MOST’s social media account is live! First light expected on October 21st! (1pm UK time) 🔭🧪

4-meter Multi-Object Spectroscopic Telescope (4MOST) @4most-eu.bsky.social · Sep 17

Welcome to the official 4-metre Multi-Object Spectroscopic Telescope (4MOST) Bluesky account! Stay tuned for our first-light events coming very soon, and updates on all of the amazing science we will be completing over the years to come!

📷: Y. Beletsky/ESO

#4most #ESO #telescope #astronomy

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Reposted by Denis Erkal

Michael Merrifield @astromikemerri.bsky.social · Sep 20

Let us name those who should take responsibility for this situation. The senior management of universities failed to negotiate a sustainable system of funding, and then sleep-walked into mess.

But will they be held accountable? Of course not.

www.theguardian.com/education/20...

Quarter of UK university physics departments at risk of closing, survey finds

Four out of five making staff cuts as physicists say findings are ‘great concern’ for UK’s leadership in important areas

www.theguardian.com

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Denis Erkal @derkal.bsky.social · Sep 3

Sorry to hear!

Denis Erkal @derkal.bsky.social · Sep 3

Why? Politics in the state or something more specific?

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Denis Erkal @derkal.bsky.social · Aug 22

Here’s the Cygnus loop with a Seestar S50. It’s so big that one mosaic won’t fit it so I stitched two of them together. The total exposure is about 4 hours. It would be cool to go even wider and deeper. 🔭

Picture of the Cygnus loop showing lots of stars and thin clouds of gas which came from a supernova explosion

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Reposted by Denis Erkal

Stephen Green @stephenrgreen.bsky.social · Aug 17

@aircanada.bsky.social

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Reposted by Denis Erkal

Stephen Green @stephenrgreen.bsky.social · Aug 17

Stranded in Italy thanks to Air Canada. They say by email that they can't find any flights in the next three days and offer a refund -- ignoring EU 261/2004 regulations that they have to rebook on *any* airline. They do not answer the phone.

AC has absolute contempt for its customers and employees.

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Denis Erkal @derkal.bsky.social · Aug 4

That would be cool! I agree, I was thinking of a by-eye type pointing given the beam width.

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Reposted by Denis Erkal

The StarXiv ✨ podcast @starxiv.bsky.social · Aug 4

Episode 17 has dropped! Tune in to hear Payel & Michelle talk about about a dark matter subhalo detection, the problem(s) with super massive black holes, massive star clusters in the Sparkler, speedy white dwarfs and more! 🔭☄️ starxiv.com/2025/08/04/e...

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Denis Erkal @derkal.bsky.social · Aug 4

Yes, it’s super annoying since this used to be very useful. The issue is it thinks 3e19m is ~56 kpc instead of ~1 kpc but who knows what other units are/will be wrong. Maybe they’ve started using AI for their units?

Screen shot of Google search for (3e19m)/(1 kpc) which gives an answer of 55.7 instead of the correct answer of 0.97

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Denis Erkal @derkal.bsky.social · Aug 3

That’s awesome! I was looking to make something like this for outreach. That’s impressively cheap… I’ll be very curious to hear how you get on with it. What do you plan to do for determining where you’re pointing the antenna?

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Denis Erkal @derkal.bsky.social · Jul 24

Anyone else notice any weird unit issues with Google lately? (3e19 m)/(1 kpc) gives 55.7 instead of ~1. Not good if you like using Google for quick unit conversions 🔭

Screen shot of a Google search showing (3e19 m)/(1 kpc) gives 55.7

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Reposted by Denis Erkal

Michele Bannister @astrokiwi.bsky.social · Jul 2

New potential interstellar object in the South: 168 hr arc but e already 9+/-1. H=11.
Follow-up encouraged! 🔭

Scout: NEOCP Hazard Assessment

NASA's Near-Earth Object (NEO) web-site. Data related to Earth impact risk, close-approaches, and much more.

cneos.jpl.nasa.gov

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Reposted by Denis Erkal

Paul McMillan @mcmillan-astro.bsky.social · Jun 30

Non-hot take: The "AI will kill us" discourse was a distraction from the real problem: it removes the young end of the skilled knowledge workforce. They are harder to train, because AI can do it for them. They can't get jobs, because AI can do it for their bosses. www.theguardian.com/business/202...

Number of new UK entry-level jobs has dived since ChatGPT launch – research

Vacancies for graduate jobs, apprenticeships, internships and junior jobs with no degree requirement have dropped 32%, Adzuna finds

www.theguardian.com

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Denis Erkal @derkal.bsky.social · Jun 26

I didn’t mean to trash talk LSST, just that even with this initial processing and without stretching it’s already close to what you had so it’s already pretty good. I look forward to how deep it can be pushed!

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Denis Erkal @derkal.bsky.social · Jun 26

Come join us at Surrey! Please get in touch with questions on any of the fellowships (junior to senior), and if you're interested but not sure what you're eligible for, contact me. 🔭

Payel Das @payeldas.bsky.social · Jun 25

If you want to join our wonderful astrophysics research group here at Surrey, please get in touch with @derkal.bsky.social!

Denis Erkal @derkal.bsky.social · Jun 17

Considering a senior UK fellowship (ERF, URF)? We have a great group at Surrey and our internal deadline for the ERF is July 8th. We are looking for a light-touch application: CV and 1 page research statement. I'm the contact person, so send questions/material to me

www.ukri.org/what-we-do/d... 🔭

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Denis Erkal @derkal.bsky.social · Jun 25

Do you know if the processing was optimized for LSB features or was it the standard pipeline? By eye the depth doesn’t seem that different from your Mihos+2017 paper

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Denis Erkal @derkal.bsky.social · Jun 25

Very nice @chrismihos.bsky.social! Do you have a sense of the surface brightness limits of Rubin given your previous work?

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Denis Erkal @derkal.bsky.social · Jun 23

Wow, look at that increase in depth!

John F Wu @jwuphysics.bsky.social · Jun 23

My mind is absolutely blown by these stellar halos nearby NGC 4364!

Left: DESI Legacy Imaging Surveys (DR10)
Right: Newly released @vrubinobs.bsky.social imaging!!!

#AstroSci 🧪🔭

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Reposted by Denis Erkal

NSF–DOE Rubin Observatory @vrubinobs.bsky.social · Jun 23

Introducing...your sneak peek at the cosmos captured by NSF–DOE Vera C. Rubin Observatory!

Can you guess these regions of sky?

This is just a small peek...join us at 11am US EDT for your full First Look at how Rubin will #CaptureTheCosmos! 🔭🧪

#RubinFirstLook
ls.st/rubin-first-look-livestream

A sprawling, textured field of galaxies scattered across the deep black of space. It is filled with the delicate smudges and glowing cores of galaxies of many shapes, sizes and colors, as well as the bright multi-colored points of stars. The image focuses on a collection of interacting galaxies connected by delicate streams of stars. At top center lies a large elliptical galaxy that is dense and smooth, like a polished stone glowing with golden light. Like delicate spider silk or stretched taffy, these stellar bridges link the large elliptical to the few larger galaxies beneath, evidence of past collisions.

All throughout the image, thousands of galaxies gather in clusters or are spread throughout, like glittering gems strewn on a table. Some are sharp-edged and spiral, like coiled ribbons; others round and diffuse, like polished pebbles. Still others are just smudges of various colors against the black of space. The background is peppered with pinpoint stars in reds, yellows, and blues, crisp against the velvet black.

A cosmic tapestry of glowing tan and pink gas clouds with dark dust lanes. In the upper right, the Trifid Nebula resembles a small flower in space. Its soft, pinkish gas petals are surrounded by blue gas, and streaked with dark, finger-like veins of dust that divide it into three parts. It radiates a gentle, misty glow, diffuse and soft like the warmth of breath on a cold hand. To the lower left, the much larger Lagoon Nebula stretches wide like a churning sea of magenta gas, with bright blue, knotted clumps sprinkled throughout where new stars are born. Both nebulae are embedded in a soft tan backdrop of gas that is brighter on the left than on the right, etched with dark tendrils of dust and sprinkled with the pinpricks of millions of stars.

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Denis Erkal @derkal.bsky.social · Jun 17

Considering a senior UK fellowship (ERF, URF)? We have a great group at Surrey and our internal deadline for the ERF is July 8th. We are looking for a light-touch application: CV and 1 page research statement. I'm the contact person, so send questions/material to me

www.ukri.org/what-we-do/d... 🔭

Ernest Rutherford Fellowships

Ernest Rutherford Fellowships (ERF) enables early career researchers with clear leadership potential to establish a strong, independent research programme. They encourage talented researchers in UK un...

www.ukri.org

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