The last few weeks have been rather infuriating. Clear skies during the day, but come sunset, low cloud rolls in and covers the critical area where C/2011 L4 has been lurking.

But  last night the gaps were bigger and lasted long enough to make it worthwhile getting the binoculars out. Normally I would have opened up the observatory, but with 15mph – gusting 20 mph, the roof would have taken flight. Even then, the target still  would have been obscured by the observatory roof and the house.

Sweeping the area with a pair of 10×50’s I thought we found it, but soon realised that M31 isn’t Comet shaped 🙂 A little further down  and there it was. After a few minutes of marvelling at my first comet sighting since Holmes, I was surprised how large it looked in my 7 degree field of view, but soon realised that tunnel vision has taken firm control where the brain only sees the object itself – ignoring the rest of the field of view. The core was bright and I estimated the tail to be about 0.5 of a degree long and angled about 30 degrees clockwise from the vertical.

Not being able to get a camera on the scope, the only way to image the comet was to use the DSLR on a tripod. Being at such a low altitude, I stared to get star trailing after 10 second exposures, so had to up the ISO to 1600 in order to get a decent degree of detail. I also had to time my exposures in between gaps in the clouds scudding across the sky.

Session Data

  • Date: 31/03/2013
  • Time: 20:28 – 20:53 UT
  • Avg Temp: 2.9c
  • Air Pressure: 980Mb,
  • Humidity: 51%,
  • Dew point: -2.6c,
  • Seeing: Unknown, Transparency: Poor, Airmass: 17.7

The above gives you a feel for how windy it was. All that cloud was moving right to left.

This was taken with the lens set at full zoom of 55mm

This is a 50% crop of the above image. It looks like there are two tails or is it just a concentration of material forming a V shape at the outer edges.  This wasn’t visible  visually, but I would like to get a better look at it through a scope to examine this area more carefully.