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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.
The launch is scheduled for 2132 (BST) on May 27 and Dragon comes over the UK 15 minutes later. Steve is saying that you could watch the launch on TV (at 2132) and go into your garden 15 minutes later (at 2147) to see the Dragon go over. You could, if you wish, also see an ISS pass at 2120 (BST).
Dragon will be lower than ISS at this point so it will go into shadow sooner. I would think at 21:30 (BST I assume) it will still be illuminated. The twilight sky will be quite bright though.
Thanks for that Steve. It is always fun to see a spacecraft go over only 15 mins or so after it has launched from the Cape. This one will be particularly interesting because of the manned aspect. Sometimes there are interesting things to see as well if the second stage of Falcon 9 is venting propellants.
Proxima is too far south for us at a declination of 62 deg S. Wolf 359 is a bit further away (7.9 light years compared to proxima’s 4.2) but it is visible from the northern hemisphere as faint red dwarf in Leo.
It’s a nice outreach activity and the baseline is certainly much larger than the 2au baseline that Gaia has but the resolution of the LORRI camera on NH in 4×4 bin mode is only around 5 arcsec (2.3 m FL, 13.5 um pixels). The current Gaia DR2 error for the parallax of Proxima is 0.2 milli-arcsec (mas). Assuming a high SNR in the images LORRI might get astrometry accurate to 50-100 mas. The 25 times improvement in baseline won’t compensate for the factor of 250 loss in precision. The NASA publicity doesn’t really make this very clear.
John,
Yes, the current orbit from MPC for C/2019 Y1 (ATLAS) gives positions which are off by 5′.2 in RA and 12′.8 in Dec.
The position from JPL Horizons is much closer.
Mid time: 2020-04-15 20:23:52, S up.
The weather didn’t cooperate last night so I have no new images of C/2019 Y4 (ATLAS). I’ve been playing with images taken over the last few nights using FITSwork and iterative Gaussian sharpening (thanks to Nick Haigh for putting me on to this). These images show the development of the inner coma region over three nights. The first two were taken with by camera in 1×1 bin mode. Unfortunately I don’t have this for the last night so I have used a resampled versin of my normal 2×2 bin mode. All use the same Gaussian sharpening params (r=4.13, 20 iterations, 100% strength). You can see the components separating as the move relative to one another.
