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Pretty impressive sight. I was emerging from my observatory, which has its door on the N side, at saw it as I looked up.
iPhone pic here: https://britastro.org/observations/observation.php?id=20250324_214542_63483fe3de3e8a2eI also caught it on my N facing meteor camera.
Yes this prediction in the Schneider paper was discussed a few posts above (3 March), Dave.
As I said then, I can see no real astrophysical basis for this.The rest of the article is not bad at all. Thanks for sharing it.
The link to Forbes does not work for me. I found it here: https://www.forbes.com/sites/jamiecartereurope/2025/03/20/a-star-may-explode-next-week-in-once-in-80-years-event—what-to-know/
Edit: this link does not work either. The real link, bizarrely and unhelpfully, contains three hyphens in a row which seem to get corrupted into a single long line.
Those of you planning to attend this meeting in God’s Own County, and with time available, might like to see this article on local astronomy haunts: https://britastro.org/journal_contents_ite/an-astronomical-day-out-in-rural-cheshire
Great to hear this development, Andy. I especially look forward to seeing what sort of photometry you can extract.
I would also be interested to hear how faint you can go with different exposures and therefore whether this Smart Scope, or others, might have value in nova searches (where detections by a amateurs using 135mm lenses and digital cameras have been successful).
I’ve started work on the “real time photometric alert script”, I hope I can outrun T CrB … My plan is to have this run on a Raspberry Pi, using siril-cli (for stacking (say) 4 x 10 sec exposures (green channel), Source-extractor (for creating a catalog of detected stars and instrumental photometry), scamp for doing the astrometric solution and some custom scripts to check the photometric results for consistency and generate the actual trigger. We will see…
This is an interesting project, Heinz-Bernd. Keep us posted and if it works out perhaps you can write it up for the VSS Circular.
Good luck!Yes I am familiar with that analysis Steve. I can’t think of an astrophysical reason why there should be a fixed number of orbits between eruptions.
A paper on the “Binary Parameters for the Recurrent Nova T Coronae Borealis” today reports the masses of the white dwarf and the red giant that comprise this binary system. The authors conclude that the WD mass is 1.37 +/- 0.01 M-sun. This would place it close to the Chandrasekhar instability limit.
A submission to the PASP today considers the “Legacy of Henrietta Leavitt: A Re-analysis of the First Cepheid Period-Luminosity Relation”:
https://arxiv.org/abs/2502.17438The authors re-analyse Leavitt’s first Period-Luminosity relation using observations of the same set of stars but with modern data and methods of Cepheid analysis. They go on to consider the discovery of two types of Cepheid populations and the implications for Hubble’s measurements of the distance to our neighbouring galaxies.
I will touch on this topic at the Deep Sky Section meeting, as two key Type II Cepheids were actually discovered in 1890 by David Packer, who for many years was a BAA member living in Birmingham.
This conference paper examines the recent debate about phosphine and other potential biomarkers in Venus’ atmosphere and whether cosmic rays might actually destroy chances of life (they conclude they don’t, but this is based on cosmic ray simulations rather than actual data): https://arxiv.org/abs/2502.13371
This AJ preprint on ArXiv predicts that T CrB will become the brightest nova ever observed in X-Ray: https://arxiv.org/abs/2502.10925
The authors also discuss the future evolution of the white dwarf towards the Chandrasekhar limit.
Cloud in Yorkshire? Whatever next!
Seriously though, another fascinating album. I presume “Collinson” was EH Collinson, who joined the BAA in 1920 and had gone to school in Yorkshire.You might want to start a new thread with your de-forking question, Ken.
There is an old thread here which includes a reference to Martin Mobberley’s JBAA paper (though the link is corrupted):
https://britastro.org/forums/topic/meade-lx200-classic-telscopeFascinating, David. Thanks for sharing.
Not sure BAA members would Don those eclipse outfits today!I always find such scenes from the years leading to WW 1 highly evocative
An ATel today reports an increase in accretion rate in the last couple of weeks: https://www.astronomerstelegram.org/?read=17030
What a splendid short film. Thanks for sharing this, Richard.
I wonder what else John Goodricke might have accomplished has he lived longer.In answer to a question following my talk on T CrB, I mentioned that some had predicted that the neutrino burst from the eruption might just be detectable on Earth. However, a pre-print on ArXiv today suggests that the burst might actually be too weak for such a detection.
As ever, time will tell.
Another analysis of the recent great dimming of RW Cep is appears in an A&A pre-print on ArXiv, “Atmospheric dynamics of the hypergiant RW Cep during the Great Dimming“.
The authors present spectroscopic observations which reveal changes in the star’s atmospheric dynamics during the fade. It is interesting to see they cite Robin Leadbeater’s analysis published in the VSS Circular.
Michael Woodman, who independently discovered the 1946 eruption of T CrB as a 15-year old schoolboy in 1946, was guest of honour at the BAA meeting on January 18. He was presented with the BAA VSS Charles Butterworth Award.
Many thanks to all those present who helped to make it as special day for Michael and his family.
A photo of Michael (taken by Philip Jennings) is attached.
Attachments:
Article on “A Predicted Great Dimming of T Tauri: Has it Begun?“ here
https://arxiv.org/abs/2501.06378An AJ preprint from Tracy L. Beck (Space Telescope Science Institute).
An A&A preprint on ArXiv today discusses the recent super-active phase SAP of T CrB.
The SAP lasted between 2015 and 2023, during which T was about three-quarters of a magnitude brighter than normal. A similar SAP was observed prior to the 1946 eruption.
The authors find that the SAP was triggered in the inner part of the accretion disc, increasing the disc temperature and the mass accretion rate at the white dwarf surface. The higher temperature should have further enhanced the mass transfer and sustained the SAP.
The SAP abruptly stopped in 2023, implying that the disc has returned to a quiet phase. At this time accretion dropped to a very low level. Recently T has been gradually brightening again and accretion has picked up. Note that when sufficient material has accumulated on the surface of the white dwarf, it triggers the thermonuclear runaway that appears as a nova eruption.
