17P / Holmes - DEC 06, 2007

Step 1
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Observation Notes:

It's hard to believe that it's been a month since I last sketched this comet. It has truly become monstrous. To the naked eye, it is a large soft patch glowing in Perseus, and is still an incredible thing through binoculars. I no longer see any color in it--just a pale gray. It still possesses that trilobite appearance, but is much softer now. There is no visible pseudonucleus, and the central fan has become a soft spine. It looks to me like the southwest half of the coma is brighter.

Using the astrometric eyepiece for measurements has been out of the question for some time now. Based on my sketch and comparison to the star field in Starry Nights Pro, I made some rough estimates:

  • Central Fan: 12 x 60 arc minutes
  • Coma: 60 x 75 arc minutes

Subject17P / Holmes
Position*04:00 UT - Perseus: [RA: 03:06:57.2 / Dec: +48:13:53]
SizeCentral Fan: 12 x 60 arc minutes
Coma: 60 x 75 arc minutes
Brightness*~ 3.0 vMag
Date/TimeDecember 6, 2007, 9:30 PM
(December 7, 2007, 04:30 UT)
Observing Loc.Flagstaff, AZ - Home
Instrument15 x 70 Oberwerk Binoculars
ConditionsClear, breezy
Seeing4/10 Pickering
TransparencyMag 6.0 NELM
*SourcesAerith.net; Starry Night Pro Plus 5

*Based on published data.

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About this Entry

This page contains a single entry by Jeremy Perez published on December 6, 2007 12:05 AM.

17P / Holmes - Not As Faint As You Might Think was the previous entry in this blog.

Scutum-Sagittarius Milky Way Photo is the next entry in this blog.

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