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Observation by Alan Snook: Comet 46P Wirtanen

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Alan Snook


Alan Snook


2018 Dec 16 - 00:40


2018 Dec 16 - 11:45


46P Wirtanen

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Field centre

RA: 03h55m
Dec: +19°59'
Position angle: -11°37'

Field size

4°02' × 4°07'

  • Canon 18x50 IS binoculars
  • Field 3.7 degrees

East Kent

Target name

Comet 46P Wirtanen


Comet 46P Wirtanen

About this image

Unaided zenith limiting magnitude is 5.5m.I would guess the Comet's combined magnitude is about 5. It is not visible to the unaided eye. In the binoculars it is a round fuzz with a noticeable non-stellar nucleus. No structure seen and no impression of colour. The size is very difficult to estimate as the outer parts of the coma are not much different to the sky background but I put the diameter at circa 40 arcminutes.

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David Swan
David Swan, 2018 Dec 16 - 12:41 UTC

Excellent visual report as always, Alan. I too can't make out 46P with the naked eye - but I have seen it with my 10 x 50 bins. The good news - from my perspective - is that it is moving east for early evening observation at a good altitude over the north sea, which is quite dark. I hold out hope for a positive naked eye observation in the next few days.

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