The color change of Comet C/ISON's dust coma

We measured the color of the coma, and found that the outer part of the coma is slightly redder than the inner part,” Planetary Science Institute Research Scientist Jian-Yang Li said.

Li presented the findings Oct. 9, 2013 at the American Astronomical Society’s Division for Planetary Sciences 45th Annual Meeting in Denver.

[link to www.psi.edu]

This image shows the color change of Comet C/ISON's dust coma. The white dot at the center of the coma marks the location of the nucleus. ISON's dust coma appears to be less red near the nucleus than it is further away from the nucleus. Although the color change is actually very small, it could be an indication of relatively more water ice particles near the nucleus. Those icy particles evaporate, as they move outward, makes the coma appear redder.

On October 10, 2013 the NASA STEREO-A satellite will observe ISON for the first time.

[link to www.isoncampaign.org]

The latest light-curve for Comet ISON (compiled October 02, 2013 by Matthew Knight).

[link to www.isoncampaign.org]