Home > Comet, Ephemeris Program, Observing > 12/18/2018 – Ephemeris – My observations and what to expect from Comet Wirtanen

12/18/2018 – Ephemeris – My observations and what to expect from Comet Wirtanen

December 18, 2018

Ephemeris for Tuesday, December 18th. The Sun will rise at 8:15. It’ll be up for 8 hours and 48 minutes, setting at 5:03. The Moon, 3 days past first quarter, will set at 4:23 tomorrow morning.

This past weekend the skies finally cleared so I could see and photograph Comet Wirtanen at its brightest and closest to the Earth. The Moon was interfering and will be making the sky brighter until this next weekend. Also the Moon will be moving toward the comet, coming closest to it on the 20th. The comet is rapidly moving away from the Earth, so its brightness is dropping as the skies brighten. Last weekend I could not say that I saw it with the naked eye. It was visible in my 10X50 binoculars as a faint smudge. The comet had no discernible tail. Even though it’s living up to its magnitude estimates, the problem is that the comet’s brightness is spread over a large area, making its surface brightness so much less than a star of the same magnitude.

The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

Comet Wirtanen and the Pleiades

Comet Wirtanen below and the Pleiades above at 9:24 p.m. EST, December 14, 2018. Canon EOS Rebel T5, f/5.5, 30 second., ISO 3200, fl 55mm, tracking.  I processed this image with GIMP. increasing the contrast and removing some of the moonlight.  The greenish coma (head) is due to carbon (C2) emissions common in comets.

For more comet photographs go to http://spaceweather.com/.

%d bloggers like this: