Originally Posted by StickyGreen

was just reading up on light years and this shit still boggles my mind...

A light year (or light-year, or lightyear), is the distance light travels in one year: about 9.461 × 1015 metres (9.461 petametres), or about 5.879 × 1012 (nearly six trillion) miles.

misc facts:

- It takes 8.3 minutes for light to travel from the Sun to the Earth (a distance of 1.58 × 10-5 light years).

- The most distant space probe, Voyager 1, was 13 light hours (only 1.5 × 10-3 light years) away from Earth in September 2004. It took Voyager 27 years to cover that distance.

- The nearest known star (other than the Sun), Proxima Centauri is 4.22 light years away.

- The center of our galaxy, the Milky Way, is about 28,000 light years away.

- The Galaxy is about 100,000 light years across.

-The nearest large galaxy cluster, the Virgo Cluster, is about 60 million light years away.

-The particle horizon (observable part) of the universe has a radius of about 46 billion light years, but light from the edge of the observable universe was emitted only 13.7 billion years ago (the age of the universe). The figures differ because distant objects have continued to recede from us due to cosmological expansion (see Hubble's law).

- One gigaparsec is equal to approximately 3.2 billion light years.