... What does the surface of Saturn's moon Rhea look like? To help find out, the robot Cassini spacecraft currently orbiting Saturn was directed to fly right past the second largest moon of the gas giant planet late last month. 30 Doradus: The Tarantula Zone . ... The Tarantula Nebula is more than 1,000 light-years across - a giant emission nebula within our neighboring galaxy the Large Magellanic Cloud. ... R136: The Massive Stars of 30 Doradus . ... Proxima Centauri: The Closest Star . ...