How to spot galactic date of Comet Siding Spring and Mars

The Earth's red twin is set to have a rare cosmic date with a comet that will pass close to Mars' orbit on Oct. 19 -- and you're invited to witness the close encounter of the galactic kind.

Comet Siding Spring, also known as C/2013 A1, will approach Mars and will be viewable by skywatchers. It is estimated to buzz even closer to Mars than the moon orbits around the Earth.