http://en.wikipedia.org/wiki/Light-second
http://en.wikipedia.org/wiki/Second
http://en.wikipedia.org/wiki/Arcsecond
http://en.wikipedia.org/wiki/Right_ascension
http://en.wikipedia.org/wiki/Longitude
http://en.wikipedia.org/wiki/Frame_of_reference
http://en.wikipedia.org/wiki/Great_attractor
