4 ms·

Yeah, I wonder why the camera didn't catch the comet's tail. There's a possibility all the volatile components have already been burned off by the solar wind (

by drcube 12y ago

Yeah, I wonder why the camera didn't catch the comet's tail. There's a possibility all the volatile components have already been burned off by the solar wind (which is what causes the tail). That would make this either a very old, or very small comet. Or one that wasn't that icy to begin with.

ColinWright 12y ago
Or the truth, which is that's it's far enough away from the sun that it's currently so cold that there are no volatiles being boiled off. Hence there is nothing for the solar wind to be blowing.
- codezero 12y ago
  Technically the outgassing is considered a sublimation since it's not a liquid ;) The outgassing is mainly a function of the magnitude of the solar radiation (which varies quite a bit) and the cross section of the comet, so it's doubly variable and may outgas really far from the Sun if the conditions are right.
DanielleMolloy 12y ago
The comet is currently not close enough to the sun to have the activity leading to a large, visible tail (this would be in conflict with the mission's aims). However, emissions have been detected since April 2014.
- codezero 12y ago
  There's no set distance from the Sun for where a comet tail will develop, as it depends a lot on the size of the comet and the magnitude of the solar wind at the particular position. This comet's aphelion is around Jupiter, and comets have been observed with tails (from telescopes, not naked eyes! :P) at that distance. This comet probably is too small though. See my other comment for a better explanation of why the tail wouldn't be visible in this image. Here's a cool image of Comet Humason that was taken while it was near Jupiter in the 60s, it's pretty epic, one of the most awesome comets I came across in my studies, this image is from an obscure journal that I can't find now, but I found the image on a forum :P http://foro.tiempo.com/index.php?action=dlattach;topic=129406.0;attach=160470;image http://foro.tiempo.com/index.php?action=dlattach;topic=12940...

by drcube 12y ago

ColinWright 12y ago

Or the truth, which is that's it's far enough away from the sun that it's currently so cold that there are no volatiles being boiled off. Hence there is nothing for the solar wind to be blowing.

codezero 12y ago
Technically the outgassing is considered a sublimation since it's not a liquid ;) The outgassing is mainly a function of the magnitude of the solar radiation (which varies quite a bit) and the cross section of the comet, so it's doubly variable and may outgas really far from the Sun if the conditions are right.

DanielleMolloy 12y ago

The comet is currently not close enough to the sun to have the activity leading to a large, visible tail (this would be in conflict with the mission's aims). However, emissions have been detected since April 2014.

codezero 12y ago
There's no set distance from the Sun for where a comet tail will develop, as it depends a lot on the size of the comet and the magnitude of the solar wind at the particular position. This comet's aphelion is around Jupiter, and comets have been observed with tails (from telescopes, not naked eyes! :P) at that distance. This comet probably is too small though. See my other comment for a better explanation of why the tail wouldn't be visible in this image. Here's a cool image of Comet Humason that was taken while it was near Jupiter in the 60s, it's pretty epic, one of the most awesome comets I came across in my studies, this image is from an obscure journal that I can't find now, but I found the image on a forum :P http://foro.tiempo.com/index.php?action=dlattach;topic=129406.0;attach=160470;image http://foro.tiempo.com/index.php?action=dlattach;topic=12940...