Now you REALLY need to leave X (and so does your employer…) Staying on X is morally indefensible. It is the Epstein Island of social media. http://telescoper.blog/2026/01/07/now-you-really-need-to-leave-x-and-so-does-your-employer/

Trump won't stop at Greenland. I'm sure he also intends to take over Teeland, Fairwayland, Bunkerland, Holeland...

New Publication at the Open Journal of Astrophysics: "Going beyond $S_{8}$: fast inference of the matter power spectrum from weak-lensing surveys" by Cyrille Doux (Université Grenoble Alpes, France) and Tanvi Karwal (U. Chicago, USA) https://doi.org/10.33232/001c.155045

Maynooth University Library Cat Update Maynooth University Library Cat has endured the very cold weather we have had recently, but when I met him this lunchtime he was rather hungry. So much so that he scratched my hand in his anxiety to get at the food I put out for him... P.S. There seems to […]

New Publication at the Open Journal of Astrophysics: "A targeted, parallax-based search for Planet Nine" by Hector Socas-Navarro and Ignacio Trujillo (Instituto de Astrofísica de Canaria, Spain) https://doi.org/10.33232/001c.155004

The #bbcnews Editor has sent this to #bbc journalists. #Kidnapping must NOT be called #kidnapping, in case #trump is offended. #selfcensirship #ukpol #maduro #venezuela #themadcountry

A Frosty Return So here I am, back on campus at Maynooth University. I took the longer route than usual to my office this morning as I thought the South Campus would look pretty with all the frost around, as indeed it was: It was well below freezing last night. Today was refuse collection day […]

Den Bortkomne Sauen The weather has been much colder for the past few days, which is probably why this piece of music popped into my head and I thought I'd share it here. It's a Norwegian folk song called Den Bortkomne Sauen ("The Lost Sheep") and it's played by Annbjørg Lien on Hardanger […]

I'm very concerned that an ambulance and an emergency response car were called to a house down my street. I don't know who lives there; they only moved in recently. The ambulance just left with its siren on. Sounds serious. 😟

Den Bortkomne Sauen The weather has been much colder for the past few days, which is probably why this piece of music popped into my head and I thought I'd share it here. It's a Norwegian folk song called Den Bortkomne Sauen ("The Lost Sheep") and it's played by Annbjørg Lien on Hardanger […]

Very few news outlets reporting on the number of people murdered by US forces in Venezuela, estimated to be at least 40. https://www.hindustantimes.com/world-news/venezuela-strike-death-toll-how-many-civilians-and-soldiers-died-in-us-attack-101767508030061.html

Sunrise, Sunset, Solstice and Perihelion I was on the train earlier today when I remembered that we are getting close to the time when Earth reaches its perihelion, i.e. the point in its orbit when it is closest to the Sun. This occurs at 17.15 GMT tomorrow (Saturday 3rd January 2026), in fact […]

Not a Weekly Update from the Open Journal of Astrophysics – 03/01/2026 There bing no papers to report, instead of doing one of the regular Saturday updates, I'd like to take the opportunity afforded by this pause to thank everyone who has supported the Open Journal of Astrophysics this year – […]

Trump is evil. Explosions reported as smoke seen rising in Venezuelan capital Caracas https://www.irishtimes.com/world/2026/01/03/explosions-reported-as-smoke-seen-rising-in-venezuelan-capital-caracas/

Sunrise, Sunset, Solstice and Perihelion I was on the train earlier today when I remembered that we are getting close to the time when Earth reaches its perihelion, i.e. the point in its orbit when it is closest to the Sun. This occurs at 17.15 GMT tomorrow (Saturday 3rd January 2026), in fact […]

Not that many people here will need it, but as an indicator it's interesting: In case you're looking for an alternative New Year resolution, Denmark has a new people's movement: Danmark skifter, Denmark switches, which aims to help people regain focus, change their social media habits and get […]

2026: The Year Ahead For last year’s words belong to last year’s languageAnd next year’s words await another voice.And to make an end is to make a beginning. From Four Quartets, ‘Little Gidding’ by T. S. Eliot. So it's New Year's Day. Athbhliain faoi mhaise dhaoibh! For me this brings the […]

Question: Should auld acquaintance be forgot, And never brought to mind? Answer: Yes.

December 31st – Richard Hoffman All my undone actions wandernaked across the calendar, a band of skinny hunter-gatherers,blown snow scattered here and there, stumbling toward a futurefolded in the New Year I secure with a pushpin: January’s picturea painting from the 17th century, a still life […]

Lick Observatory Damaged I missed, until now, the news that on Christmas Day, high winds accompanying a violent storm seriously damaged the historic Lick Observatory. The gales were strong enough to rip one of the shutters from the dome of the 36" refracting telescope and send it crashing onto […]

Joshua or Lazarus?

Alegoría del Invierno – Remedios Varo Alegoría del Invierno (Allegory of Winter) by Remedios Varo, 1948, gouache on paper, 44 ×44 cm, Museo Nacional Centro de Arte Reina Sofía, Madrid, Spain. http://telescoper.blog/2025/12/29/alegoria-del-invierno-remedios-varo/

It can't be that hard for AI to reach human levels of intelligence, if all it needs to be able to do is recognise which pictures have traffic lights in them.

The Voice of Niels Bohr The other night I watched the 2023 film Oppenheimer on TV. I had seen it before, on a plane flight, and enjoyed it, though I thought it was overlong. Fortunately it was a long flight. Watching it again a couple of days ago reminded me of something that struck me first […]

Weekly Update from the Open Journal of Astrophysics – 27/12/2025 Since the last update we have published four papers which brings the number in Volume 8 (2025) up to 201. Adding the 12 papers in the Supplement, this brings the final total for the year up to 213, and the total so far published […]

I can't help feeling that the Mrs Brown's Boys Christmas Special could have been improved by the inclusion of a comedy element.

Christmas dinner menu: roast beef Chateaubriand, with red wine gravy, honey-roast carrots and parsnips, Brussels sprouts, and roast potatoes; preceded by smoked salmon with asparagus, followed by Christmas pudding and, later on, cheese and port.

I find it interesting, from a linguistic point of view, how the French "Noel" (or "Noël") and Irish "Nollaig" evolved from the Latin "Natalis". The Welsh "Nadolig" may be a sort of Celtic missing link...

I will of course be having Coles de Bruselas with my dinner this evening...

Nollaig shona daoibh go léir! Here we are then, Christmas Day. I thought I'd do a quick yule blog in between finishing a rather late breakfast and starting the preparations for dinner*. Let me just wish you all a Merry Christmas, Nollaig Shona, Nadolig Llawen, Fröhliche Weihnachten, Joyeux Noël […]

From Private Eye:

A Christmas Eve Message Since Christmas Eve - variously known elsewhere in Europe as Nochebuena, Heiligabend, veille de Noël, vigilia di Natale, Juleaften - is upon us, I wonder if I might crave the momentary indulgence of all readers of this weblog, in order to discharge a by no means […]

The two papers published this morning bring Vol. 8 (2025) to a close. We have published 213 papers this year (201 in the regular issue and 12 in a supplement). This brings this year's publishing activity to a close. Thank you for your support and we'll see you in 2026 with Vol. 9!

New Publication at the Open Journal of Astrophysics: "The explosion jets of the core-collapse supernova remnant Circinus X-1" by Noam Soker and Muhammad Akashi (Technion, Haifa, Israel) https://doi.org/10.33232/001c.154770

New Publication at the Open Journal of Astrophysics: "Quantifying the Fermi paradox via passive SETI: a general framework" by Matthew Civiletti (City University of New York, USA) https://doi.org/10.33232/001c.154771

I see that Oppenheimer is on telly soon. Is it a Christmas movie now? "Now I am become Death, the destroyer of worlds. Merry Christmas."

The Counties of the United Kingdom (according to ChatGPT) Regular readers will know that I sometimes educate the Great Unwashed about the facts of British geography (including where the North begins). I have decided to enlist the help of Generative AI to help me with this task so, with a little […]

Vol. 8 of @OJ_Astro now has 199 papers, not counting the supplement, with just one more day of publishing before we close for the year. Will it make 200? Tune in tomorrow and find out!

New Publication at the Open Journal of Astrophysics: "Transverse Velocities in Real-Time Cosmology: Position Drift in Relativistic N-Body Simulations" by Alexander Oestreicher (University of Southern Denmark), Chris Clarkson (QMUL, UK), Julian Adamek (Universität Zürich, CH) and Sofie Marie […]

New Publication at the Open Journal of Astrophysics: "On the statistical convergence of N-body simulations of the Solar System" by Hanno Rein, Garett Brown and Mei Kanda (U. Toronto, Canada) https://doi.org/10.33232/001c.154745

O Tannenbaum – Vince Guaraldi Trio http://www.youtube.com/watch?v=_fh133ZO1AE http://telescoper.blog/2025/12/22/o-tannenbaum-vince-guaraldi-trio/

It's a shame the word "chevelure" (originally meaning something like "a head of hair") didn't catch more on in Astronomy: 1791. Herschel, in Phil. Trans., LXXXI. 78. "A star of about the 9th magnitude, surrounded by a milky nebulosity, or chevelure, of about 3 minutes in diameter."

The Winter Solstice 2025 Sunlight at dawn on the Winter Solstice at Newgrange Just a quick note to point out that the Winter Solstice in the Northern hemisphere happens today, Sunday 21st December 2025, at 15.03 UT (GMT). In Dublin, sunrise yesterday (20th December) was at 8.37 am and sunset at […]

On this darkest solstice day of the year, my heart has dimmed, waking up to learn of the loss of dear colleague and mentor, Yannick Mellier. Yannick will be known to most as the lead of the amazing Euclid Space Telescope which will revolutionise our understanding of the Dark Universe 🧵🔭

**Wishing for a Mastodon plushie this Christmas?** 🎄 We’re giving away two of the new ones for free to two random people who boost and favorite this post! Winners will be announced on December 25th, just like last year. If you’d like to support our server and […] [Original post on mastodon.de]

The #decembersolstice, ie the #wintersolstice in the Northern Hemisphere, takes place tomorrow at 15:03 GMT (16:03 in Belgium) on Sunday 21 December 2025.

Weekly Update from the Open Journal of Astrophysics – 20/12/2025 Since the last update we have published two more regular papers, described below, which brings the number in Volume 8 (2025) up to 197, as well as the 12 papers in yesterday's Supplement, and the total published for the year up to […]

Art in Bruges For various reasons I find myself thinking about this little clip from the 2016 film In Bruges, starring Brendan Gleason and Colin Farrell. It's set in the Groeningemuseum in the city of Bruges. You can read an interesting post about the art in the film here. You will see that the […]

Supplement to the Open Journal of Astrophysics – “Pulsar Science with the SKAO” The topic of this Supplement is Pulsar Science with the Square Kilometre Array Observatory and it includes updates to the Science Case for the SKAO, the previous version of which is 10 years old. All the papers are […]

"Most researchers would receive more recognition if assessed by article-level metrics than by journal-level metrics." https://journals.plos.org/plosbiology/article?id=10.1371%2Fjournal.pbio.3003532 PS: It's important to add that article-level metrics are preferable anyway. This is true whether […]