Monday, September 16, 2013

Comet ISON Whitmer R-Band Image Analysis - Update by amateur astronomer Bruce Gary

The topic of Comet ISON seems to be coming up more and more these days. I have been in touch with Bruce Gary, an amateur astronomer who has been very closely keeping his eye on Comet ISON.

I am not sure what constitutes the title amateur, as going by Bruce's work experience, he has been involved in the area of Astronomy for decades and holds a degree in astronomy from back in 1961. You can also see by the quality of his work thus far on ISON, that he knows what hes talking about.

Comet ISON, August 12th 2013

Below is his latest update which is only a few hours old. Within the update he explains that he has examined images that Dennis Whitmer took of Comet ISON this morning (in the USA I assume) and has created an animation and a graph as a result.

By Bruce Gary via, 15 September 2013 - Dennis Whitmer obtained 40 useful images this morning (20 20-sec & 20 60-sec). I've used 14 of the 60-second images to create a GIF animation.

Animation using the first 14 images from the 60-second image set. 14-inch Celestron, binned 2x2. 

Below is an analysis using 4 of the 60-sec images for coma's brightness versus diameter.

R-band brightness versus amount of coma included in photometry aperture, for Sep 15 (Whitmer data); trace of previous date's Whitmer fit shows that there was a 0.17 magnitude brightening from Sep 11 to Sep 15, versus the predicted 0.12 mag brightening.

The brightening during the past 4 dates is compatible with the simple model prediction and calibration uncertainty. The coma structure difference is probably not real given the fact that all images are binned 2x2 and the image scale is 1.56 "arc/pixel.  


Wherami said...

These are fantastic! I think ISON is becoming talked about even more because TPTB have banned anymore space based images to be released to the public. You have to be suspicious and VERY interested when they start hiding the data.

Laron said...

Very suspicious!

dorothi said...

can not stay hidden for long!!!