I thought it would be interesting to see if I could calculate how quickly comet 46P/Wirtanen appeared to be travelling across our line of sight, using the data shot to create a widefield image. I worked out the resolution of the image in arcseconds per pixel and by measuring pixels between the comet at known times, I was able to do a little bit of mathematics to calculate a speed of 9.6 km/s, which I am happy to report concurs with the published data about the comet.
Telescope:
Camera:
Exposures:
Canon 85mm lens @ f2.8
Canon EOS 1Dx
4 x 60s at ISO 800