Comet C/2012 K5 is ready for chasing
Posted 20 December 2012 - 08:24 AM
Posted 20 December 2012 - 01:14 PM
Posted 20 December 2012 - 02:55 PM
Posted 20 December 2012 - 06:03 PM
It must be pretty diffuse
Quite the opposite - its quite condensed and bright - are you sure you looked in the right place?
Posted 20 December 2012 - 06:48 PM
Posted 21 December 2012 - 01:26 AM
I'll be checking back in on this one to see how things change.
Posted 21 December 2012 - 01:34 PM
Tried to see it with an 8 inch Dob at 5AM and didn't see anything. It must be pretty diffuse.
As Tonk said..its bright and easy to find, it looks elongated but couldnt detect any tail, as when we observed it on the morning of 16th this month...the sky wasnt very clear with the thin cloud cover sailing over getting views inbetween. It was near alioth and hence made for an easy hop. will try again before the moon moves in..
Hoping that it may prove useful to some I am attaching a map that will give a rough idea of where the comet will be the next few days..
Posted 22 December 2012 - 11:28 AM
Posted 22 December 2012 - 03:07 PM
I first found it about a degree and a half (below) from the star Dubhe at about 11:30 pm with a 70% waxing gibbous Moon high in the sky.
I got a little sleep and went back out and found it again about 2:30 am after the Moon had went down.
The comet was visible with low power but not my 9 x 50 finder. This comet seemed small to me and maybe had a brighter nucleus with adverted vision. A faint fan shaped tail was visible with hints of being longer than was obvious. At 11:30 pm it formed a nice triangle with a pair of stars and after about 3 hours when I came back out it had moved about 23 arc/min up next to a 9.4 mag star. When I defocused this star to about the size as the comet it was about the same mag.
Hopefully I will get my 12" dob on it soon. Sketch is flipped to match refractor view and shows movement between my two observing times.
Posted 22 December 2012 - 11:26 PM
Posted 23 December 2012 - 12:18 AM
Posted 23 December 2012 - 02:08 AM
Posted 23 December 2012 - 10:12 AM
Posted 23 December 2012 - 11:54 AM
Posted 23 December 2012 - 11:41 PM
You’re welcome, Ira. I’m glad everyone is having fun with this comet.
I’ve updated my ephemeris and graphics for this comet to its osculating orbital elements of epoch 2013 JAN 01.0. Previously they were for epoch 2012 NOV 29.0. Other sources still depend on much earlier epochs, despite the effects of planetary perturbations. The elements I use were provided by Dr. Aldo Vitagliano’s highly accurate Solex astronomical numerical integration program: http://main.chemistr...~alvitagl/solex . I then run them through the orbit determination algorithm of his friend Jean Meeus. BTW, Aldo is a member of the Cloudy Nights message board. See his latest contribution at post #2 in the thread at: http://www.cloudynig...5570752/page...
The comet’s coordinates in my ephemeris are given in decimal form. That’s to ease interpolation, i.e. the process of estimating positions at moments other then 00 UT.
Linear interpolation usually suffices to determine an intermediate position P:
A = Position at Day 1
B = Position at Day 2
F = Fraction of a Day since A ( 12 hours would be 0.5 )
P = A + ( B – A ) x F
However, when an object appears to traverse the sky rapidly as this comet is now, second degree interpolation will provide greater accuracy:
A = Position at Day 1
B = Position at Day 2 ( nearest 00 UT to time in question )
C = Position at Day 3
D = ( C – A ) / 2
E = ( C + A ) / 2 - B
F = Fraction of a Day since B ( F can be negative, although F² is always positive )
P = B + D x F + E x F²
My comet ephemerides and related graphics are at: www.CurtRenz.com/comets
Posted 24 December 2012 - 06:32 AM
The comet sported a somewhat condensed nucleus and a rather short tail that fanned out in a narrow fashion.
By the time the moon had set, the transparency had improved and I had a far better view of the 8th-magnitude comet. At 360x, the comet's motion was apparent in the span of approximately ten minutes.
While I couldn't see C/2012 K5 (LINEAR) through the 5" f/5 finder scope earlier, I was able to spot it at 35 and 45x after the conditions had improved.
Posted 24 December 2012 - 10:51 AM
I forgot to mention seeing was only so so. I'd say transparency of 2 or 3 out of 5
Posted 24 December 2012 - 12:28 PM
Posted 24 December 2012 - 01:13 PM