Latest image (09:30, 14 Mar 2012 UT) shows the tail extending faintly for total length of about 2/3 of a degree including coma. C3 images a field out to 30-32 solar radii from the Sun, or diameter of 60-64 solar radii (~17 deg), depending which source you get the figures from.
Thanks Liz for your comments. Nice image there Rob of the new comet, the next few days will be interesting as to if it will survive.
Here is my image of comet Lovejoy from last night 14-3-12. It is 13x4 minute exposures with Astrograph and Astro 40D at ISO 1600. Measured the tail to be just over 1 degree in length. Almost leaving Lepus and will enter Orion in 2 days.
Hi all, here is my image from last night 16-3-12, comet Lovejoy has passed into the constellation of Orion from Lepus. This is 21x4 minute exposures with atrograph f3.3 and Astro 40D at ISO 1600. The tail is still over 1 degree in length although getting very faint for the left 2/3 of it.
Hi all, with the comet getting extrememly faint thought I would try ISO 800 instead of 1600 to see if the finer grain would help to reveal the object better. I doubled the exposure time to 8 minutes, and the results were good, with the comet only just showing up on the standard view. The inverted view is clearer, but to get any of it on the standard view shows me it is an improvement even though sky tranparency was only good and not excellent.
Image is a stack of 14x8 minute exposures with Atrograph and astro 40D.
It really just comes down to your total exposure as to how faint you can image. Apart from that the only improvement might be lower temperature and better transparency.
Anyway, looks like I was able to get an image of the new Sungrazer comet (C/2012 E2) that appeared a few days ago. This was made very deep in twilight on March 10, using a Canon 350D + 70-200 2.8 lens set to 135mm f3.5 and combining 72 x 3.2sec ISO400 exposures. Possibly the must difficult comet observation I've ever attempted.
Hi all, tonight was the first chance I have had to try for comet Lovejoy since the 17th March. The sky was clear with good transperancey. As the comet moves further into Orion there is a lot of faint nebula which makes finding the comet impossible. I took 15x8 minute exposures with astro 40D at ISO 800 and Astrograph.
The first image has a red X at the ephemeris position of the comet. http://i638.photobucket.com/albums/u...y/62f83c5e.jpg
I'm glad you followed the comet as long as you did, it looks like you a problably the last. I was going to have a go last night but decided to do a comet search instead (and as you noted the starfields are getting very crowded so it would be just about impossible to find).
Thanks Terry it has been a good journey. I don't think any sized scope could pick it up now with the sky background full of nebulosity that is brighter than the comet.
Good luck Terry, hope you can discover another soon.
It really just comes down to your total exposure as to how faint you can image. Apart from that the only improvement might be lower temperature and better transparency.
Anyway, looks like I was able to get an image of the new Sungrazer comet (C/2012 E2) that appeared a few days ago. This was made very deep in twilight on March 10, using a Canon 350D + 70-200 2.8 lens set to 135mm f3.5 and combining 72 x 3.2sec ISO400 exposures. Possibly the must difficult comet observation I've ever attempted.
Terry
This is a terrific, terrific catch. It made me jump from my chair. Lucky for you it is a big chair or you would be at the end of an international lawsuit for injuries!
I should note that observations by a lot of people on this list appear in the paper (Lester, Rob, jjj, Justin, Trevor, etc). So congrats!
There is a huge amount of info in this paper, but if I was summarise briefly:
1. Postulated complete disruption of nucleus occured 1.6 days after perihelion as intense heat conducted into the interior of the nucleus causing it to blow apart from the inside.
2. C/2011 W3 expected to be the first of a new cluster of Sungrazers in the 21st Century. Lets hope so!
3. C/2011 W3 period ~700 years, a possible scenario for origin of comet within the Kreutz comet evolution is given.
4. Sublimation of dust near the sun caused the apparent fading of the comet and tail around perihelion.