Forum Replies Created
-
Posts
-
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).
Thanks to all the speakers and the technical people who put the material online – and of course the organisers too. David Swan
Hello James. I am a fan of imaging transients and noticed this one a few days ago on David Bishop’s website. IMHO it certainly is worth flagging this on the forum – as a (visible) PSN or SN in a Messier object does not occur that frequently. Great image! The weather where I am is atrocious. David
Peter Carson has managed to capture a much better image (see his member’s page). Nonetheless, under poor conditions (wind ESE – straight from sea towards scope (!), and lots of condensation on the corrector in misty air) I acquired five reasonably steady frames. Comphot estimate: mag 10.4 in photometric aperture of diameter 130arcsec – but take this with a pinch of salt.
As Nick has said, the orbit is obviously very well determined. I updated MPCORB in Astrometrica, and the comet was spot on the predicted position.
