You are here

Stellar Heavyweight

October 17, 2010

The state fairs of Arkansas, Mississippi, and Texas are in full tilt this weekend. If you visit them, there's a good chance you'll overindulge on the corndogs, funnel cakes, and deep-fried everything.

A star in a nearby galaxy sounds like it might have overindulged, too. It's not just hefty -- it's heavier than a star should be.

Most models of star formation say that stars can't grow heavier than about 150 times the mass of the Sun. The intense radiation from such a hot, massive star should prevent more gas from falling onto its surface, limiting its mass.

But this summer, a team led by Paul Crowther of the University of Sheffield reported the discovery of four stars that exceed the limit. The stars are in the Large Magellanic Cloud, a companion galaxy to the Milky Way. The team observed them with telescopes in Chile, and looked at old pictures from Hubble Space Telescope.

The study's heaviest star appears to be about 265 times the mass of the Sun. It most likely was even bigger at birth, but it's blown much of its gas back into space.

The problem, though, is that it's a loner, and it's hard to get an accurate measurement of a single star's mass. The best measurements come from stars in binary systems. The team did find a massive binary, but the heaviest of its stars is only about 150 times the Sun's mass. That still makes it one of the heaviest stars yet discovered -- give or take a corndog or two.


Script by Damond Benningfield, Copyright 2010


Get Premium Audio

Listen to today's episode of StarDate on the web the same day it airs in high-quality streaming audio without any extra ads or announcements. Choose a $8 one-month pass, or listen every day for a year for just $30.