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Ditto for me. I haven’t refocused mine for years (3.8mm, f/0.8). My main problem is spiders. Now that planes are mostly gone they are a major source of false triggers on my cams. I have a brush on a long pole for dealing with them but they don’t stay away for long.
Did you mean the Circulars (at the link provided by Martin) or the e-bulletins? The e-bulletins were archived somewhere but I can’t find them on this site.
I agree. It was an inspired idea from Andy and Dominic to get these going. They have been really popular and I hope that we can continue them in some form even when things get back to normalish.
I’m just resurrecting this thread since it started with a post from me on May 2nd tentatively predicting a nice comet for around about now but with, hopefully, sufficient caveats that members wouldn’t be disappointed if it fizzled. The first post in the thread included a chart for May 20 and this morning I managed to get an image here which matches the field if not the splendour. C/2020 F8 is probably somewhere between mag 6 and 7 at the moment and it is certainly not an easy object but it is there and if you are up early it is worth searching out. It goes under the pole at midnight on May 26 and from then on it will be better in the evening but it is now fading. Images received will appear in the Comet Section archive here.
Eric has provided me with his data. The geometry is not very favourable since our stations are too close together but here is the ground track. It was out over the English Channel off the north coast of France.
I caught it from Chelmsford and would be happy to run the other stations’ data through UFO orbit to get a groundtrack when their data is available.
David, Thanks. At the moment this is definitely not a comet for the general public to get excited about. I got it again this morning. It was much higher (5 deg vs 2.5 deg) but there was more cloud and haze so the two cancelled out. Picture attached. Bear in mind that this was with a 200mm FL lens so quite a small field of view. The comet is still quite hard to spot.
My great surprise too! They have lifted some quotes that I gave to a journalist who writes for Forbes magazine. The original article is here.
Here you go David. An image from Chelmsford this morning is here. It is not really world-shattering stuff but at least it is visible from here now. Not quite the as good as Rhemann’s image from Namibia.
The craters are named by an IAU committee. You could always try to get elected to it if you want to make your suggestions! Some of its decisions are controversial but most definitely not in this case.
You can call the craters anything you want in the same way that the International Star Registry (if they still exist) will name a star after your dead hamster for a small fee. Unless you are NASA nobody will take any notice.
Yes, right in the centre of my SE cam FoV from Chelmsford. The video is here.
The impact velocity is very high and so the effect is more like a sudden detonation than a gradual excavation. Bear in mind that the size of the crater is much larger than the diameter of the impacting object. There is a lot of kinetic energy in a 100m diameter object going at 20 km/s and this is released very quickly in a small volume some way below the surface. The resulting shock waves are spherically symmetric until they break the surface and this means that, with the exception of very oblique impacts craters will be circular.
Ray. It doesn’t seem that PC to me. It is more that it is trying to get a bit of balance. I believe that the vast majority of craters on the Moon are named after men.
I didn’t know that either! There is a nice list of them on Wikipedia.
That’s not the way it works David. I’m the Director so I take credit if it turns out well. As a Mr. Swan you can take the blame if it fizzles!
BTW the Sun (newspaper not star) is already hyping it and it appears to have its own Twitter account.
Great image from Hubble. I have an image from Chelmsford taken 14 hours earlier and it is interesting to compare the two. You can see why having a 2.4m telescope in space is such a good idea. In three days time it will have been in orbit for 30 years. Let’s hope they keep it working for a long time to come.
I’ve put a timelapse of that all-sky video here. This is made from 1s max stacks of the video frames animated at x5 real time.
