Distance to the sun's nearest neighbour star, Proxima Centauri A parsec (parallax of one arcsecond) is a unit of length equal to just under 31 trillion km (about 19 trillion miles), 206265 AU, or about 3.26 light-years.
Because of the speed at which the earth and the moon move relative to the sun, a total solar eclipse can never last more than how long?
