Enjoying EarthSky? Subscribe.

110,975 subscribers and counting ...

By in
on Dec 10, 2012

Schematic of a parsec

One parsec is how far away a star must be for it to shift by one arcsecond as the earth goes around the sun. It’s equal to 30 trillion kilometers or just over three light-years! Credit: Wikipedia user Srain.

One parsec is how far away a star must be for it to shift by one arcsecond as the earth goes around the sun.  It's equal to 30 trillion kilometers or just over three light-years!  Credit: Wikipedia user Srain.

Schematic of a parsec