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Hi Robin. Very interesting. Am I right in thinking this would be consistent with an accretion disk in an optically thick state? Or are there other – perhaps more likely – explanations?
I’ve been to York many times. There is the full range of establishments: from eye-gougingly expensive but ineffably cool bars all the way to what might be described by some (more precisely, those southerners who rarely mix with provincials) as dens of iniquity. All said in jest 😉
After quite a bit of frustration, I am now delighted with the performance of the Hyperstar. Good grief though. Centering the corrector plate, ensuring the sec. mirror holder is not tilted with respect to the corrector, rotating the corrector to minimise zonal errors, minutely altering the sensor – Hyperstar distance, altering the tilt of the sensor slightly…… Need I go on.
Sorry, this has nothing to do with Sirius B. It was a big deal though. Please don’t eject me from the thread 😉
You know this of course, but it is also worth saying that the greater altitude that Procyon achieves from our vantage point should help with seeing. I just need to get the Hyperstar off my C8 and put the secondary mirror back for native FL imaging. After all the faff with getting things aligned just right…
For those who are interested and haven’t visually observed or imaged this yet, this transient is still quite bright and nicely placed in Leo Minor for evening obs.
K Itagaki’s latest image on David Bishop’s site puts the SN brightness at around 13.6 (clear filter, presumably V mag zeropoint).
Unfortunately there’s been quite poor weather in NE England recently – with just snatches of clear sky – so I haven’t been able to get at this object.
That’s a quite reasonable comment. Some issues are great, others not. I like Sue French’s deep sky bit, as she highlights stuff that looks good to amateur visual observers who do not have a giant Dobsonian.
Sorry for being a party pooper with the link, Jack. I think you have raised an interesting topic for discussion and I wanted to put here the link to the programme for anyone who is interested.
There are several issues here aren’t there – for example about how one interprets a loose statement like ‘Mars, our nearest neighbour’ that was used on the Sky at Night. Of course, as people have pointed out, ‘which planet can get closest to Earth?’ is a quite different question to ‘which planet is most often the closest to Earth?’, and indeed ‘which planet is closest to Earth now (or indeed any specified time)?’.
Revealingly, Chris Lintott, an accomplished astrophysicist, checked that Mars was closer than Venus at the time of broadcast, but didn’t even think to check the distance to Mercury at that time. I am not saying any of you are guilty of this, but I think we can probably say that many people will just think of the sequence of orbital ellipses around the sun and conclude ‘it must be either Venus or Mars, mustn’t it.’
Also interesting is that (I hope I recall this correctly) the programme researchers looked through articles around this topic and found that there wasn’t anything published on this question. On something so simple, this is very interesting.
P.S. I second Jeremy’s point about More or Less. I subscribe to the podcast. I was hooting with laughter as Tim Harford took a nutritionist to task about the difference between ‘facts’ and what might be ‘good policy’ – relating to data on sugar consumption over time.
Hi Alex – I’m a Geordie ;).
Just a bit of a fun observation. They’ve obviously corrected the figure for the web; here’s the print version. How does this happen? Surely they just use stock maps.
David
Indeed there are different average measures.
If you put all the days of a randomly chosen year in a hat, pull one out, and then have to guess which planet is closest to us on that day: Mercury would be the wisest choice.
Yes, I listened to this section on the BBC’s More or Less
In case anyone is interested, there is an article in Sky and Telescope on the mysterious ‘Cow’ transient that appeared six months ago. Therein are further links to the research literature (Open Access).
https://www.skyandtelescope.com/uncategorized/cow-celestial-event-puzzles-astronomers/
I agree with Andrew and Owen. For me, I found that once it had moved over the north sea into dark skies, I could star hop to it using binos. It has a very diffuse appearance which responds to averted vision. I have also used GOTO with my C8 and looked at it with my Televue 32mm plossl. Not an impressive object visually, but there.
I would suggest that you get a >10Ah power pack manufactured by Celestron or SkyWatcher or such like. Just check that it has the right 12V output sockets for your dew heater straps (but I expect you know this!).
I have a Celestron lithium mini-tank also – it is useful for illumination and USB charging, but no good for the more demanding peripherals!
Dominic, our wizard on all things IT (and other subjects), reported a while back that animated gifs are not supported on this site. You might be pleased to know though that the comet archive does support animated gifs. Michael Jaeger’s swooshing comet tails are a regular feature there. David S
Nice spectra, both. It is good to hear Robin that you can subtract the contribution of airglow and light pollution – if only we could all do that for all observation modalities! The comet is rapidly moving out of the worst light pollution for me and is now a) not a problem to locate in binoculars (albeit not impressive visually) b) a good imaging target with an extended coma within reach of my camera. I get a mag of 5, which is very close to Nick’s value (4.9).
