isoncampaign.org - 10/24/13
Comet Lovejoy and the effect of the solar wind.
Comet C/2012 S1 (ISON) is a dynamically new sungrazing comet. This makes it a particularly unique object that we hope will be a big help in our understanding of Oort Cloud comets and primitive solar system material. Sungrazing comets are pretty useful in this respect, as they get much closer to the Sun that "ordinary" comets, and thus their surface gets much hotter than your typical comet. The result is that material that typically stays more or less "inert" on a comet's icy surface may begin to vaporize, giving us the chance to spectroscopically look at the comet and distinguish new compositional elements. Fun stuff for sure, but the truly unique thing about sungrazers is that they server a dual purpose: they also teach us about the Sun!
Historically, comets were our first clue that there exists a solar wind - an ever-present outflow of particles from the Sun - that causes their sublimated material to flow behind them in the long tails we see. This realization was a big deal as we had no way of sending probes into space so see what was actually going on out there. Instead, the comets were our probes!
