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Robin. Thanks for that. To emphasise how dominant the H-alpha emission is at the moment the attached is a comparison of the field in Sloan g’, Sloan r’ and narrowband H-alpha. Spot the nova!
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Not many CAPs on my cameras (only 19 so far this month, first one on the 12th). Rather more 49 Andromedids (33 this month from July 14).
NLC have indeed been a bit thin on the ground from Chelmsford. My cameras have picked them up on around 30% on mornings in July but most were faint. The two good displays were on June 29 and July 8:
https://nickdjames.com/NLC/2026/nlc_20260629_0200_ndj.mp4
https://nickdjames.com/NLC/2026/nlc_20260708_0100_ndj.mp4Very interesting to see how the spectrum evolves. My Sloan photometry shows that it is currently getting redder as it fades. I assume that this is due to the current dominant H-alpha emission. The g’-r’ was around 2.2 at maximum and is around 2.7 now. The great weather we have had in July means that I have been able to observe it practically every night since the outburst.
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The nova was still showing 0.05 mag amplitude variations last night (July 7/8). Check star 1-sigma is 0.009 mag. Mean mag is now 10.67 r’, 12.99 g’.
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Got another time-series last night although there was cloud around. It looks like it is starting to fade.
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Just started a time-series run on the nova. It looks a bit brighter tonight. Currently 9.85 r’, it was 10.20 r’ last night.
Comet 169P/NEAT is in the same field so I can get a comet and a nova at the same time. The comet is around mag 15.
I did around 3 hours of Sloan r’ time series photometry on this nova last night in good conditions. The mean magnitude was 10.20 in r’ and 12.45 in g’ so it is a very red object. The time series showed a small hump of around 0.05 mag at around July 3.95.
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I got a series of Sloan r’ frames of it last night although conditions were poor with lots of drifting cloud:
https://britastro.org/observations/observation.php?id=20260628_095628_79afe0e2787a87ee
I’ll measure the photometry later. By tonight it will probably be too far south for me to get anything useful.
I only managed to get a short run on the asteroid last night. A preliminary lightcurve from Tycho attached.
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I use the same IMX291 camera modules that are used in the GMN meteor network but retaining the IR filter so that they can be operated in colour mode. They can be used in power-over-Ethernet mode so are very simple to install and they can stream MP4 video to multiple clients. I just put the modules in a waterproof dome.
https://www.aliexpress.com/item/1005003139136600.html
Have a look at the talk I gave in Elgin a few years ago:
youtube.com/watch?v=IvTMV1CVUyM
Any camera based on a Sony Starvis sensor would probably work fine.
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It is a shame that the audio in the livestream is so ropey. The audio in the room seemed perfectly OK so I wonder if the stream was using a different microphone. It is not often that you can’t hear me!
Here is an animation of its final hours taken from LASCO C2:
https://britastro.org/observations/observation.php?id=20260405_091544_fe658e5ddc7bfd61
Yes, it broke up prior to perihelion and nothing came out at the expected position so there will be no headless wonder in the evening sky. That’s a shame but it was always a significant possibility given the small size of the nucleus.
Some of the dust released ahead of the breakup did appear to survive, and is visible in the coronagraph images, as a dust cloud on the “wrong” side of the Sun. This could possibly be detectable as a very low surface brightness feature in the morning sky. Highly unlikely, particularly since the Moon will interfere, but imagers are a resourceful bunch.
We’ll see.
It is currently behind the occulter in C2 but we should get an indication about whether it has survived in few hours.
https://soho.nascom.nasa.gov/data/realtime/c2/
You can make a movie using this page:
That really is a beautiful image. The full-sized image is here:
https://images-assets.nasa.gov/image/art002e000192/art002e000192~orig.jpg
the EXIF suggests that this was taken using a Nikon D5, 22mm, f/4, 1/4s, ISO 51200. Apollo 8 had the famous Earthrise photo. I think this is better.
That’s a shame, but it was going to be a difficult observation anyway. Still worth keeping an eye on the launch time and ephemeris for interesting opportunities from the UK.
If the launch takes place as currently planned (April 1, 22:24 UTC) we may be able to see the Trans-Lunar Injection Burn from the UK 25 hours 37 minutes later so around 2026-04-03 00:01 UTC although the spacecraft will be low above the SW horizon. An ephemeris is available from JPL Horizons.
From Chelmsford the spacecraft rises around 23:49 on April 2 and at the time of TLI it will be 10 deg up at an azimuth of 209 deg.
Almost 60 years ago, on 1968 December 21, Chris Taylor saw the Apollo 8 TLI from Chelmsford. There is a really good S&T write-up here:
https://skyandtelescope.org/stargazing-and-observing/stargazers-corner/apollo-8-view/
I would like to reproduce that observation!
A lot of the topics covered in this thread are dealt with in detail in the 2017 review paper I cited in my original news article on this comet:
https://link.springer.com/content/pdf/10.1007/s11214-017-0446-5.pdf
It is well worth a read. See, for example, section 6.2 which discusses the breakdown of the inverse square law in relation to, amongst other things, heat flux.
