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Confirmation via ATel (no doubt there will be more over the next days): https://www.astronomerstelegram.org/?read=16944
Bad luck Eric. Hopefully you can catch it tonight. Given how short the eruption is, every obs counts.
The recurrent nova M31N 2008-12a’s ~annual entry onto the stage has just been announced:
2024-12-13.0074 UTC with a magnitude of 18.6 CV, Jingyuan Zhao using the Burke-Gaffney Observatory remotely.Matt Darnley (LJMU) calls for follow up observations over the next 3 to 4 days. This RN fades rapidly. And it is faint, 18th mag at max. Matt has sent a ToO observing request for follow-up observations with Swift.
Well it looks like humps, Ian. But they are pretty small and somewhat irregular for fully grown superhumps. It was also fading quite quickly. I hope you will get some more data.
Looking into the BAA VSS and AAVSO databases, there are fewer obs of this archetypal dwarf nova in recent years. This is a real pity, so it’s good you are following it. Occasionally it does odd things. There have been a few epochs when it stopped superoutbursting, eg 3 years in the 1980s, plus some more recent times. And in 2020 it apparently showed no outbursts at all for ~4 months.
An ApJL preprint on ArXiv today reveals the the discovery of a Nova Super-Remnant (NSR) surrounding T CrB. This is only the third known NSR. It at least 200,000 years old. Turning to the forthcoming eruption, the authors predict there will be no fluorescent light echoes seen after T CrB erupts, but there might be dust-scattered, continuum light echoes during the year following the nova eruption.
On the lighting front, there might be an opportunity to play back Dundee City Council’s own nett zero plan: https://www.dundeecity.gov.uk/sites/default/files/publications/net_zero_transition_plan_2024-2030.pdf
This states that 25% of its emissions are from the electricity used in its buildings sector. This is the second largest contributor (after heating of buildings). As a consequence, their action plan item OE2 is about addressing lighting in buildings (though not OF buildings; I would hope this would be included).
An A&A preprint on ArXiv today might me be interest: Two epoch spectra-imagery of PV Cep outflow system.
The authors describe features in the associated HH object and their kinematics.
They report a newly-formed HH knot, which they presume formed during the large maximum of PV Cep star in 1976-1977.
ATel 16912 on “Continued monitoring of activity in T CrB: Rapid intensification of He II and spectroscopic gyrations” discusses recent spectroscopic changes in data from the ARAS group: https://www.astronomerstelegram.org/?read=16912
The overall significance is not clear, though there does appear to be a change in accretion environment and rate around October.
This is definitely feasible. Arne Henden is routinely monitoring T CrB in daylight. He is using a Newtonian stopped down to 50mm and is able to image theta CrB mag ~4.1. The other day there was a false alarm and he was able to show that there was nothing brighter than mag ~4.5.
The rise time is 1-5 hours.
Latest data shows that the rebrightening episode, which lasted ~9 days, is now over with the star having faded to 18th mag. Additional rebrightenings are possible.
Many people enjoyed the nova V1674 Her that erupted in 2021 (was it really that long ago?). A pre-print of an ApJ paper has just appeared which probes the early part of the eruption in unprecedented detail, shedding now light on the events at the white dwarf that triggered the eruption.
Thanks Ian. I note that the star dipped (to mag 16) and re-brightened ~4 days ago. Classic UGWZ. I wonder if there will be further such episodes.
Tonny Vanmunster reports the emergence of 0.16 mag amplitude humps 13 days into the outburst of this putative UGWZ dwarf nova. The period is ~0.067 days.
Spectroscopy from the GOTO team leads them to suggest this is a WZ Sge type dwarf nova: https://www.astronomerstelegram.org/?read=16858
If so, one might expect superhumps to develop.
LHAASO also reports gamma ray flaring on Oct 5: https://www.astronomerstelegram.org/?read=16850
Looking at the AAVSO light curve, it was ca 0.5 mag brighter in BVRI (13.2V) on Oct 6 compared to Oct 3.
