Originally posted by Paul Dirac II
Boulders can be seen in one of the photos here--
http://news.yahoo.com/first-comet-close-ups-rosetta-spacecraft-reveal-scientific-152257398.html
One thing I was wondering, how much effect does the radiation from the sun have on the orbit of these objects? It is about 500 million Km from the sun and as such gets roughly 100 watts per square meter of energy from the sun, as opposed to 1355 watts per square meter of radiation hitting the top of Earth's atmosphere.
I calculated a rough idea of the total energy received at about 1/4 of a gigawatt total on the surface of that comet. So going with 250 megawatts, how much actual force does that represent in terms of thinking of that in terms of solar sails presently in development? Obviously it would be pushing against a vast mass, even if that mass is tiny compared to Earth or the moon, it is still like a mount Everest flying through space.
I was thinking of the fact that force would be acting on that mass for years at a time and another effect would be the thrust given by the water streaming off the comet when it is closer to the sun. It would seem to me at least part of the time the solar pressure and the rocket pressure of the water leaving the comet would add up and increase the effect of changing the orbit of this giant mountain in space.
I wonder if you could calculate what the orbit would be without the solar pressure and see how much the orbit changes because of that pressure, I imagine it would not be a lot but it would be interesting to find out how much change it would represent.