January 15th

The Horsehead nebula in Orion
18 x 10 minutes in Ha. William Optics 132, QSI 683 camera.
I have been eager to image this for some time.
(The view to the South is now much improved after new landscaping in the neighbours garden.)



C/2012 S1 (ISON) is a sungrazing comet discovered on 21 September 2012.

During August 2013, it should become bright enough to be visible through small telescopes or binoculars, becoming visible to the naked eye by late October or early November and remaining so until mid-January 2014.

Comets often do not live up to expectations (remember Kohoutek) but if this one does it may rival some of the famous bright comets.

This animation is from two 10 minute exposures. The comet is not easy to see - look closely near the centre.

This stack of 5 10 minute images shows the trail of the comet.
The comet is moving from left to right, in the constellation Gemini.



I recently downloaded a free plate solving program, PlateSolve2, from this site.

I tried it out on an image of the comet, taken at 22:53:46 UT.



The coordinates given for the comet were, RA 07 35 33.42, DEC 31 21 13.3

Coordinates given by the Minor Planet Ephemeris Service for the middle of the 10 minutes of the image were:

2013 01 15 225400 07 35 33.6 +31 21 14
2013 01 15 225500 07 35 33.5 +31 21 14
2013 01 15 225600 07 35 33.5 +31 21 14
2013 01 15 225700 07 35 33.4 +31 21 14
2013 01 15 225800 07 35 33.4 +31 21 14
2013 01 15 225900 07 35 33.4 +31 21 14
2013 01 15 230000 07 35 33.3 +31 21 14
2013 01 15 230100 07 35 33.3 +31 21 14
2013 01 15 230200 07 35 33.2 +31 21 14
2013 01 15 230300 07 35 33.2 +31 21 15

This is in very close agreement with the platesolve value - accurate to +- 1 pixel!