The Pleiades cluster (upper left) shines brightly in the sky with the aurora borealis over Chena Dome. This photo was taken from the Angel Rocks to Chena Hot Springs trail in the Chena River State Recreation Area.
The Pleiades cluster is one of the closest star clusters to Earth (only 445 light-years away), found north-west of the constellation Taurus. It’s also known as the Seven Sisters of Greek mythology and Messier 45 (M45) in astronomical listings. M45 is an open star cluster containing over a thousand stars that are loosely bound by gravity and slowly dispersing over time.
The Pleiades is largely composed of hot B-type stars that formed about 100 million years ago (about 50 times younger than our Sun). Many of these stars are 50-1000 times brighter than the Sun!
The cluster is approximately 35 light-years in diameter, that’s over 200 trillion miles across (over 70,000 times the distance from the Sun to Neptune). All that in that tiny little dust-speck in the sky!