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I don’t have a view on whether planetary observers should have north or south up but I do wish that they would be consistent. When I’m doing Sky Notes I either have to have some slides with the original caption text upside down or the planet just flips back and forth in an irritating way.
Don’t get me started on the random orientations and even mirror imaged views that you see for Deep Sky objects (and also comets if truth be told).
The summary on the National Trust collections page is “interesting”. Next time a nearby supernova goes off we clearly need to go around wearing hard hats.
That’s a very impressive spectrum given that the current total magnitude of 4P is about 12. It is one of the brighter comets around at the moment and definitely worth following although it is a morning object. Current images are here.
The last two nights it has been brighter than mag 15 so the outburst looks to be on schedule. Tonight (Sept 6) I have 14.7 unfiltered.
Here’s an image taken this morning (Aug 10) from Chelmsford. It is around mag 16.1 in a 9.2 arcsec aperture. My most recent previous image was July 29 when it was 17.1.
CBET 5007 has designated this as Nova Vul 2021 = V606 Vul. To quote: “R. Leadbeater, Wigton, U.K., writes that a low-resolution (R about 500) spectrogram taken on July 16.915 UT (instrumentation not specified) shows strong Balmer lines in emission showing P-Cyg profiles with an estimated velocity of about 1400 km/s, adding that there are other broad emission lines including He; the spectrogram has been posted at website URL https://britastro.org/specdb/data_graph.php?obs_id=10094.”
Interesting to read that ATEL. I’ve managed to observe it on 12 of the 14 nights since discovery and my unfiltered photometry shows it still rising as of last night.
Sort of. They still allow DATE-OBS to be anything the developer likes as long as it is indicated in a comment. That means that you have to parse comments to find out what the keyword means. That is a pretty rubbish “standard” in my view. As an engineer the FITS standard is pretty much the kind of thing that I would expect a scientist to write…
The FITS “standard” is irritatingly vague about things like this and, particularly for astrometry, it is really important to know what DATE-OBS means. In most software these days it is the time that the exposure starts but sometimes it isn’t. In “good” software there is often a comment along the lines of:
DATE-OBS= ‘2021-07-26T22:03:10’ / Start of exposure
but often there isn’t and so it is always worth checking for whatever image acquisition and processing software you use.
Stewart, Yes, it’s back up to 5.6 unfiltered tonight (July 26) which is not far short of its brightest at the previous peak. I’m doing 1s exposures and it is not far off saturating my camera. It is very hazy here but I think I’ll get the binoculars out again.
The nova is about 0.3 mag brighter tonight (July 20) than it was yesterday. My unfiltered photometry is around 0.4 mag brighter than V band since the nova is so red but the trend is pretty clear. Of the other novae around V1405 Cas is brightening again although still around a magnitude below its brightest and V1674 Her is very gradually fading after its initial rapid decline.
Here’s the field. I get it around mag 12 (unfiltered re Gaia G) and a position of 20:21:07.71 +29:14:08.9 (Gaia DR2).
My last observation was on July 7.9 at 16.52. It’s in the BAA database. Richard Sargent also got some observations later that night at around 16.10. They are in the database too.
I have a ten year old APC UPS in my observatory and it is on permanently, but so is the observatory PC that it powers and a few other cameras and sensors. They are designed to be on permanently but, like all electrical things, don’t like getting damp.
Daryl – There are certainly a lot more trails on my images this summer compared to previous years. For imagers the way that you stack subframes can help to a certain extent. The animated GIF attached is the same frame stacked as average and as sigma clip. There are 5 satellite trails on this image, two bright ones and three faint. The sigma clip stack definitely suppresses the bright ones. Photometrically the two stacks are the same.
I’ve just measured it as 7.54 (2021 June 13 22:51) compared to 5.94 at this time last night. Both unfiltered ref to Gaia DR2 G so somewhere between V and R. That’s a fall of 1.6 mags in day. That’s pretty fast. I remember photographing V838 Her (George Alcock’s last nova) in 1991 but only getting it on one occasion since it faded so fast.
