Comet Holmes - December 5th 2007

Comet Holmes - December 5th 2007

In a period of 42 hours during late October 2007 this comet increased
in brightness by a factor of about half a million - this is the
largest known outburst by a comet. The cause of the outburst is not
known for certain but may have been caused by gas inside the comet's
nucleus breaking through the surface.

In this animation, of two 30 second exposures taken about 15 minutes
apart, the coma is about 20 arc minutes by 15 arc minutes, so somewhat
smaller than the moon appears to be.

http://www.martin-nicholson.info/holmes2/holmes.htm

Martin Nicholson, Daventry, England.
http://www.martin-nicholson.info/1/1a.htm
Visit the Astronomical Hall of Shame at http://www.geocities.com/queen5658/

On Thu, 6 Dec 2007 08:58:43 -0800 (PST), ukastronomy
wrote:

Comet Holmes - December 5th 2007

In a period of 42 hours during late October 2007 this comet increased
in brightness by a factor of about half a million - this is the
largest known outburst by a comet. The cause of the outburst is not
known for certain but may have been caused by gas inside the comet's
nucleus breaking through the surface.

In this animation, of two 30 second exposures taken about 15 minutes
apart, the coma is about 20 arc minutes by 15 arc minutes, so somewhat
smaller than the moon appears to be.

Hi Martin-

I think you need to use a longer exposure time- you appear to be losing
the coma in noise. As of my most recent measurement, UT 2007.12.04
06:30, the dust coma remained well defined at 51 arcmin perpendicular to
the antisolar point, by at least 65 arcmin in the antisolar direction
(the bow is well defined, but the "end" of the tail is harder to
determine).

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

On 6 Dec, 18:27, Chris L Peterson wrote:
On Thu, 6 Dec 2007 08:58:43 -0800 (PST), ukastronomy

wrote:
Comet Holmes - December 5th 2007

In a period of 42 hours during late October 2007 this comet increased
in brightness by a factor of about half a million - this is the
largest known outburst by a comet. The cause of the outburst is not
known for certain but may have been caused by gas inside the comet's
nucleus breaking through the surface.

In this animation, of two 30 second exposures taken about 15 minutes
apart, the coma is about 20 arc minutes by 15 arc minutes, so somewhat
smaller than the moon appears to be.

Hi Martin-

I think you need to use a longer exposure time- you appear to be losing
the coma in noise. As of my most recent measurement, UT 2007.12.04
06:30, the dust coma remained well defined at 51 arcmin perpendicular to
the antisolar point, by at least 65 arcmin in the antisolar direction
(the bow is well defined, but the "end" of the tail is harder to
determine).

_________________________________________________

Chris L Peterson
Cloudbait Observatoryhttp://www.cloudbait.com

You are correct - I used a longer exposure time for this morning's
images - now to find the time to proces them.

nice. Thanks for sharing and your great posts here at SAA.


ukastronomy wrote:

Comet Holmes - December 5th 2007

In a period of 42 hours during late October 2007 this comet increased
in brightness by a factor of about half a million - this is the
largest known outburst by a comet. The cause of the outburst is not
known for certain but may have been caused by gas inside the comet's
nucleus breaking through the surface.

In this animation, of two 30 second exposures taken about 15 minutes
apart, the coma is about 20 arc minutes by 15 arc minutes, so somewhat
smaller than the moon appears to be.

http://www.martin-nicholson.info/holmes2/holmes.htm

Martin Nicholson, Daventry, England.
http://www.martin-nicholson.info/1/1a.htm
Visit the Astronomical Hall of Shame at http://www.geocities.com/queen5658/