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Observation by Alan Snook: Comet 21P Giacobini-Zinner

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Alan Snook


Alan Snook


2018 Aug 06 - 21:30


2018 Aug 07 - 10:50


21P Giacobini-Zinner

  • 0.5m Dobson-mounted Newtonian
  • 8mm Ethos eyepiece x260

East Kent

Target name

Comet 21P Giacobini-Zinner


Comet 21P Giacobini-Zinner

About this image

Looks like a comet, not just a fuzz ball. I estimate it is 8th magnitude. There is a non-stellar nucleus and the coma diameter is about 1 arc minute. The tail extends to the SW for 4 arc minutes. The coma is surrounded by a fainter halo. Several times I fancied I could see a short spike projecting from the nucleus in the direction of motion. I have not put this on the sketch. No colour was detected. Motion to the ENE was obvious. In 30 minutes it moved between 2 and 3 arc-minutes.        

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