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.

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.

Just imaged the Perseverance spacecraft and its booster on the way to Mars. 

http://www.nickdjames.com/spacecraft/2020052.gif

Here's an animation of C/2020 F3 (NEOWISE) from last night:

http://www.nickdjames.com/Comets/2020/2020f3_20200728_ndj.gif

This consists of stacks of 20x10s (approx 320s total span including the camera dead time) processed using an r=2, theta=10 deg Larson-Sekanina filter. It shows the anti-clockwise rotation of the spiralling dust quite nicely and complex flows in the tail. 

I've only just got around to processing my images of C/2020 F3 (NEOWISE) from July 22. An animation is here:
http://www.nickdjames.com/Comets/2020/2020f3_20200722_ndj.gif
This shows a field of view of 33x22 arcmin processed using a Larson-Sekanina filter with r=2, th=10 deg. There are 9 frames each of around 330s duration (from 2143 - 2228). You can clearly see motion in the tail and material spiraling out from the centre of the coma. The small black dot at the centre of the coma is the reference pixel for the filter.

I have done quite a few experiments with this data and I think the parameters I have chosen are the best compromise to show detail and motion (i.e. around 300s integrations and L-S with r=2, th=10).

It always amazes me that so much relative motion is visible in active comets over such a short period of time.