spacetoday.net: Hubble finds mass limit for stars

Posted: Thu, Mar 10, 2005, 4:45 AM ET (0945 GMT)
Observations by the Hubble Space Telescope have shown that stars do not get any heavier than 150 times the mass of the Sun, astronomers said Wednesday. In a paper published in the current issue of the journal Nature, astronomers reported on observations of a dense star cluster within the Milky Way. The cluster was populous enough that standard models of star formation predicted that there should be 20-30 stars with masses of 150 to 1,000 solar masses, yet the Hubble observations detected no stars heavier than 130 solar masses. Similar research, performed on other stellar clusters, also found an upper limit for stellar masses in the range of 120-150 solar masses. Astronomers said they don't know why this upper limit exists.