APOD: Red Nebula, Green Comet, Blue Stars (2018 Dec 20)

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APOD Robot
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APOD: Red Nebula, Green Comet, Blue Stars (2018 Dec 20)

Post by APOD Robot » Thu Dec 20, 2018 5:15 am

Image Red Nebula, Green Comet, Blue Stars

Explanation: This festively colored skyscape was captured in the early morning hours of December 17, following Comet Wirtanen's closest approach to planet Earth. The comet was just visible to the eye. The lovely green color of its fluorescing cometary atmosphere or coma is brought out here only by adding digital exposures registered on the comet's position below the Pleiades star cluster. The exposures also bring out blue starlight reflected by the dust clouds surrounding the young Pleiades stars. Gaze (toward the left) across dusty dark nebulae along the edge of the Perseus molecular cloud and you'll travel to emission nebula NGC 1499, also known as the California nebula. Too faint for the eye, the cosmic cloud's pronounced reddish glow is from electrons recombining with ionized hydrogen atoms. Around December 23rd, Comet Wirtanen should be easy to find with binoculars when it sweeps close to bright star Capella in the northern winter constellation Auriga, the Charioteer.

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Ann
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Re: APOD: Red Nebula, Green Comet, Blue Stars (2018 Dec 20)

Post by Ann » Thu Dec 20, 2018 5:17 am

Wirtanen becomes not Electra, but the Pleiades, California and IC 348!

Ann
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Re: APOD: Red Nebula, Green Comet, Blue Stars (2018 Dec 20)

Post by Boomer12k » Thu Dec 20, 2018 7:40 am

And we are wet and cloudy.... me sad... :(

Great work and image though...love it...
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pferkul
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Re: APOD: Red Nebula, Green Comet, Blue Stars (2018 Dec 20)

Post by pferkul » Thu Dec 20, 2018 8:37 pm

Here is my rough estimate of what the comet looked like through my binoculars on Dec. 18. I manually drew the comet (fuzzy gray patch in lower left corner) onto a picture of the Pleiades. Not particularly striking for my optics, but then again it was 7 million miles away! This is from suburban Cleveland Ohio, the Moon was out, and there were probably some high, thin clouds as well. I was lucky to see it at all since it has been rather cloudy lately.
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neufer
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Re: APOD: Red Nebula, Green Comet, Blue Stars (2018 Dec 20)

Post by neufer » Thu Dec 20, 2018 9:41 pm

Click to play embedded YouTube video.
pferkul wrote:
Thu Dec 20, 2018 8:37 pm

Here is my rough estimate of what the comet looked like through my binoculars on Dec. 18. I manually drew the comet (fuzzy gray patch in lower left corner) onto a picture of the Pleiades. Not particularly striking for my optics, but then again it was 7 million miles away! This is from suburban Cleveland Ohio, the Moon was out, and there were probably some high, thin clouds as well. I was lucky to see it at all since it has been rather cloudy lately.
Art Neuendorffer