News Astronomy

The North Star is much heavier than previously thought

Polaris is nearly 50 percent more massive than an earlier study found

A time-lapse photo of the night sky over Coyote Buttes, Ariz., shows stars leaving circular trails around a bright point in the middle, which is the North Star.

Stars appear to circle around the North Star in this time-lapse photo of the sky over Coyote Buttes, Ariz.

Scott Smith/Corbis Documentary/Getty Images Plus

By Ken Croswell

The star marking true north is a good deal heavier than we thought.

The North Star is 5.1 times as massive as the sun, astronomers report in work submitted July 12 to arXiv.org.