Observation by Chris Hooker: Mercury, 5th November 2021

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Chris Hooker


Chris Hooker


2021 Nov 05 - 10:45


2021 Nov 05 - 16:31



  • 254mm Newtonian
  • 5x IR Barlow
  • Baader 685 nm IR pass filter & 850 nm short-pass filter
  • ZWO ASI174MM camera

0.5 msec @ F/31


Didcot, Oxfordshire

Target name



Mercury, 5th November 2021

About this image

A gibbous Mercury imaged in (initially) very bad seeing which made focusing impossible. This was apparently due to a local heat source, because after some time the seeing steadied and the image became quite good. Out of 67 captured video sequences, 24 yielded a total of 8000 good frames, which did not require selection by eye to produce usable stacks. The results are consistent with a softened WinJupos image. The bright spot in the 7 o'clock position is the crater Debussy; Kuiper is near the limb at about 8.30 but cannot be seen as a distinct feature; it is visible in the non-blurred WinJupos image.

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Martin Lewis
Martin Lewis, 2021 Nov 05 - 17:14 UTC

Good work Chris. What altitude was Mercury when imaging?


Chris Hooker
Chris Hooker, 2021 Nov 05 - 18:05 UTC

Thanks, Martin. Mercury was about as high as it gets right now, around 28 degrees altitude. I'm very glad I decided to persevere through the bad seeing, as otherwise I would have missed getting this image!


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