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Observation by Nick James: C/2020 R4 ATLAS

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Nick James


Nick James


2021 Apr 16 - 03:01


2021 Apr 16 - 06:20


C/2020 R4

  • FLI6303 + Celestron HD11



Chelmsford, UK

Target name

C/2020 R4 (ATLAS)


C/2020 R4 ATLAS

About this image

C/2020 R4 (ATLAS) is the brightest comet around at the moment. Visually it is around mag 9.5 and it is high in the sky at the start of morning twilight from the UK. It is currently moving very quickly relative to the stars (around 8 arcsec/min) and so this stack of 45 frames was done using a technique which separates the comet from the star background. The comet and stars and then stacked separately at the appropriate offsets and recombined to "freeze" the comet's motion. This technique works well on fast-moving comets when there are plenty of frames to stack.

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Like this image
Mike Harlow
Mike Harlow, 2021 Apr 16 - 09:00 UTC

Hi Nick,

Nice image and a very interesting article in the May 2021 Astronomy Now magazine on comet imaging.


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