Nick James

Forum Replies Created

Viewing 20 posts - 441 through 460 (of 882 total)
  • Author
    Posts
  • in reply to: baa electronic circulars #582489
    Nick James
    Participant

    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.

    in reply to: Webinar Applause #582487
    Nick James
    Participant

    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.

    in reply to: -5.4 exploding fireball #582486
    Nick James
    Participant

    It was going left to right in my south facing camera so the ground track is east to west.

    in reply to: C/2020 F8 (SWAN) #582479
    Nick James
    Participant

    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.

    in reply to: -5.4 exploding fireball #582478
    Nick James
    Participant

    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.

    in reply to: -5.4 exploding fireball #582475
    Nick James
    Participant

    Just let me have the M_ CSV file from UFO Analyzer. All my meteor data is here and an example file which includes this event is here.

    in reply to: -5.4 exploding fireball #582471
    Nick James
    Participant

    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.

    in reply to: C/2020 F8 (SWAN) #582467
    Nick James
    Participant

    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.

     

    in reply to: C/2020 F8 (SWAN) #582464
    Nick James
    Participant

    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.

    in reply to: C/2020 F8 (SWAN) #582459
    Nick James
    Participant

    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.

    in reply to: Did you know ! #582427
    Nick James
    Participant

    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. 

    in reply to: -3.4 southeast fireball #582420
    Nick James
    Participant

    Yes, right in the centre of my SE cam FoV from Chelmsford. The video is here.

    in reply to: Why are most of the Moon’s craters circular? #582416
    Nick James
    Participant

    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.

    in reply to: Did you know ! #582415
    Nick James
    Participant

    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. 

    in reply to: Did you know ! #582410
    Nick James
    Participant

    I didn’t know that either! There is a nice list of them on Wikipedia.

    in reply to: C/2020 F8 (SWAN) #582397
    Nick James
    Participant

    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.

    in reply to: Another comet bites the dust? #582324
    Nick James
    Participant

    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.

    in reply to: Very bright Starlink train #582311
    Nick James
    Participant

    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.

    in reply to: Crew Dragon launch #582303
    Nick James
    Participant

    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).

    in reply to: Crew Dragon launch #582302
    Nick James
    Participant

    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.

Viewing 20 posts - 441 through 460 (of 882 total)