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I suspect that Gary’s cocoa comment (and Jeremy’s Horlicks follow-up) were tongue in cheek.
I really don’t see why we need to “honour” the fact that somebody, mainly through luck and age, has reached the milestone of 50 continuous years membership. As Grant says, we have awards for achievement and it would be good if we got more nominations for those.
This is an interesting discussion and I need to declare an interest since I’m coming up to my 50th year of membership.
I’m strongly in favour of scrapping this tier of membership for the following reasons:
1) I don’t think it is fair that older (and usually more wealthy) members are subsidised by the rest of the membership.
2) I don’t think you need to be “honoured” for being a member for 50 years. Surely you’re a member because you want to be and you get something out of membership. It is not an ordeal that needs some kind of prize after 50 years.
3) When no money is taken each year we have no idea whether the honorary member is alive or dead. We’ve had cases where we have sent Journals and Handbooks to members many years after their membership of life has ended.
As David and Andy have pointed out this isn’t a final decision. It came from the trustees and has been agreed at Council but it could be overturned at the SGM if members wish. I think that would be a mistake since our complex membership tiers definitely need simplification but it is a decision for you.
The Windows/Linux argument is very out of date now. Things have moved on a lot and you can Windows for the ARM architecture so it will run on Raspberry Pis and other similar hardware. It will even run x86 binaries using an emulator. There really is absolutely no need for Windows vs Linux arguments any more. You can run both on the same machine at the same time and select the one that best fits the job in hand.
This is probably not a very helpful reply but I’ve always found NUCs rather pointless and hard to maintain, as you have found with a USB failure writing off the whole box. I run everything in my observatory off a small-form-factor, low-spec, Dell Optiplex 790 which has a mechanical hard disk. It has been sitting out in my damp observatory shed for years with no problem but I do have a stack of replacements in the garage with a disk image ready to go if it does fail. It has the advantage that you can pick them up cheap (£50 a pop from eBay) and they are easy to maintain (you can fit low-profile PCI cards for USB3 etc. and memory strips are dirt cheap). I run two cameras (an ASI6200 and an ASI293) off it plus the mount, scripting software and some other stuff. It is run headless since I do all my observing from inside and seems perfectly capable for image acquisition. It is on a UPS and is left on 24/7 but, when idle, consumes around 40W, so costs around 30p/day and this helps to keep nearby stuff in the shed reasonably dry. Maintenance consists of hoovering it out a couple of times a year to remove spiders and stuff.
Yes, already detected in China a few hours ago: https://www.astronomerstelegram.org/?read=16361
The comet designated as 1862 II is C/1862 N1 (Schmidt) discovered by J Schmidt (Athens) on 1862 July 2.87. See Cometography Vol 2, p305. Apparently just visible to the naked eye on July 7.
Thanks for the reminder about this Paul. I’ll register with the email list and will schedule a few runs on this field each clear night through December. I took the attached tonight. No sign of the nova at the moment!
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This latest outburst was a big one but it has had no detectable effect (so far) on the motion of the very massive nucleus of 12P. This plot shows astrometric residuals from three stations (970, I79 and I81) with an orbit fit that uses positions up to Nov 14. You can see that there is a large temporary displacement of the residuals on Nov 15 and 16. This is due to the biasing of the centroid of the coma by the very bright dust cloud moving NE from the nucleus. As this dust cloud fades the astrometry is returning to normal.
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Robin,
The fact that the total magnitude of the expanding dust coma is constant implies that it must be optically thin, i.e. individual dust grains are not shadowing other dust grains. That tells us that this feature is not a shadow. It is much more likely to be caused by variations in the dust column along our line of sight caused by the outflow dynamics close to the nucleus when the outburst occurred. The outburst itself is a very rapid event where gas and dust leave the nucleus at high velocities and then expand into a vacuum. That process shapes the three dimensional outflows which we then see projected onto a 2D image.
Richard Miles is the real expert on this and this comet and 29P have been giving him a lot of data to work with.
Nick.
Here is a plot of the magnitude of 12P in an approximately 9 arcsec radius photometric aperture. These are all unfiltered vs Gaia G.
While the total magnitude of the comet is constant this is within an expanding aperture, when you restrict the aperture to the region near the nucleus it gives some idea of the amount of dust in that region. The initial rise is incredibly steep. I caught it just after the outburst on Nov 14.75 and it brightened by 1.2 magnitudes in 20 minutes eventually reaching something like mag 9.3. It was 14.2 in this same aperture before the outburst so that is a rise of a factor of 100 in a few hours. That is a lot of dust coming off the nucleus in a very short time.
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And here’s tonight’s. The photocentre is still strong. No sign of any fragmentation but you wouldn’t expect any since this comet has gone through perihelion many times and has a large nucleus. Maybe some big chunks coming off but nothing more than that.
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I’ve reprocessed my images from last night and the two faint blobs were artefacts caused by some problems on three of the subframes. I’ve removed these from the stack. Updated image attached showing the prominent features to the east of the centre.
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The inner bright coma is showing quite a bit more detail now. The attached is 4 arcmin square, N up, E left, taken using the Alnitak telescope in Spain at 1906 UTC on Nov 17. There appear to be two blobs of material north of the coma. Does anyone else have any images that can confirm this?
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My latest image (and an image by Peter Carson at around the same time) does show some emerging detail in the bright inner coma:
https://britastro.org/observations/observation.php?id=20231116_205120_39e0a2e36927510e
The attached image is around 2 arcmin square, N up. The bright inner coma is now about an arcmin in diameter.
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It’s cloudy here tonight but I’m getting some images from the Alnitak telescope in Spain. This outburst is different to the others and David is right that this does look like a mini 17P/Holmes. I’m assuming the faint larger disk is the gas coma which expands quickly and the bright inner disk is the slower moving dust but don’t quote me on that.
It would be an interesting object to try spectroscopy on while it is currently bright…
I’ve just imaged the comet again and it was mag 9.4 on Nov 15.72 in a 34 arcsec aperture. This is a really big outburst and the comet should be a fairly easy visual target in a moderate telescope at the moment.
Robert. You’ll find quite a lot of different date and time formats are used in astronomy. The decimal date format is quite common for things that vary (such as outbursting comets) since it allows fairly quick mental calculation of the time between events. The next step is to get rid of years, months and days altogether and quote in terms of Julian Date. This is used a lot too but it is more difficult for the average human to interpret. If we arranged to meet at a pub at JD 2460254.333 most people (except some variable star observers) would have to go and look up a more familiar date before leaving home.
The point made by Paul Leyland up the thread is important too. In science, when we talk about quantities, we don’t want to imply more precision than is actually present. If you took it literally, July 20.82 would be 19:40:48 but we clearly don’t know the time of the outburst to that precision. The use of two decimal places in this context is used to indicate the level of precision that we think we have, i.e. around one hundredth of a day or around 15 minutes.
