Answerbag: Anonymous's questions http://www.answerbag.com/profile/465548 New Answerbag questions from Anonymous Tue, 29 May 2012 20:05:24 -0700 Tue, 29 May 2012 20:05:24 -0700 A typical comet contains 10^13 kg of water ice. How many comets would have to strike Earth to account for the 2x10^21 kg of water found on our planet? If this amount of water accumulated over .5 billion years, how frequently was Earth hit by comets? http://www.answerbag.com/q_view/922613 A typical comet contains 10^13 kg of water ice. How many comets would have to strike Earth to account for the 2x10^21 kg of water found on our planet? If this amount of water accumulated over .5 billion years, how frequently was Earth hit by comets? Tue, 19 Aug 2008 17:39:45 -0700 http://www.answerbag.com/q_view/922613 How long does a radar signal take to travel from Earth to Mercury and back when Mercury is at its closest point to Earth? http://www.answerbag.com/q_view/892203 How long does a radar signal take to travel from Earth to Mercury and back when Mercury is at its closest point to Earth? Sun, 03 Aug 2008 16:03:06 -0700 http://www.answerbag.com/q_view/892203