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Nick James

2020 Dec 8
2020 Nov 30
2020 Nov 26
2020 Nov 25
2020 Nov 24
2020 Nov 23
2020 Nov 22
2020 Nov 20
2020 Nov 11
2020 Nov 8
2020 Oct 27
There is an interesting fast mover on the NEOCP tonight. TMG0028 is 15th magnitude and moving at 50"/min. It appears to have quite rapid variations in brightness. Here is a timelapse which consists of 5s frames running at 25fps.
2020 Oct 8
2020 Sep 24
And here is a longer version tracked on the motion of the object. The magnitude was changing with an amplitude of around 0.5 mags in a few seconds so it must be a very fast rotator. It is very small though, 5-10m across, so not surprising.
2020 Sep 23
Dodging rain showers I've managed around 10 mins on 2020 SW this evening. It is around 16th mag now and moving at 25"/min. This is an animation of 10s exposures. The asteroid is the object moving SE past the bright star to the lower left.
2020 Sep 22
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2020 Sep 19
2020 Sep 14
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2020 Sep 1
2020 Aug 22
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2020 Aug 2
The Centaur upper stage of the Atlas V stack that launched Perseverance at lunchtime on Thursday was still visible last night (Saturday) at a range of around 870,000 km. It was around mag 17 but moving quite slowly (a few arcsec per min) so was measurable in individual 60s exposures. Here is an animation showing it:
http://www.nickdjames.com/Spacecraft/2020052B_20200801_2319_ndj.gif
The spacecraft will be tracked by radio very precisely on its journey to Mars but this stage is now junk and will not be. Amateur astrometry will help to define the orbit so that we can link it with observations many years in the future if it ever comes back.
The following links are a set of animations of motion in the inner coma and tail of C/2020 F3 (NEOWISE) on evenings from July 19 to July 30. All are processed using a standard Larson-Sekanina filter with r = 2.6 arcsec, theta = 10 deg. The first one is at a pixel resolution of 0".65 arcsec, all the others are at 1".29 arcsec. The files in date order are:
http://www.nickdjames.com/Comets/2020/2020f3_20200719_2128_ndj.gif http://www.nickdjames.com/Comets/2020/2020f3_20200720_ndj.gif http://www.nickdjames.com/Comets/2020/2020f3_20200721_ndj.gif http://www.nickdjames.com/Comets/2020/2020f3_20200722_2201_ndj.gif http://www.nickdjames.com/Comets/2020/2020f3_20200728_ndj.gif http://www.nickdjames.com/Comets/2020/2020f3_20200730_ndj.gif
The set on July 22 are probably the best with the longest clear run and a lot of activity going on. There is clear rotation of the spiral in the inner coma and interesting flows down the tail. By July 30th the comet had faded and the short exposures required were quite noisy.