NASA's MAVEN spacecraft, which will study the atmosphere of Mars like never before, arrives at the Red Planet tonight (Sept. 21) and you can watch it live online. Watch the live webcast beginning at 9:30 p.m. ET (0130 GMT).
July 2013 guide to the five visible planets In July 2013, Venus and Saturn pop out first thing at nightfall. The morning planets – Mercury, Mars, Jupiter – come into good view in late July. Info and charts here.