RT @Astroguyz: One of my favorite revelations courtesy of @ESA_Rosetta is just how dark comets are. #NoneMoreBlack ##CometLanding… twitter.com/i/web/status/7…
RT @Astroguyz: One of my favorite revelations courtesy of @ESA_Rosetta is just how dark comets are. #NoneMoreBlack ##CometLanding… twitter.com/i/web/status/7…