spacetoday.net: Stars evidence of new state of matter

Posted: Thu, Apr 11, 2002, 10:54 AM ET (1454 GMT)
Chandra image of 3C58 quark star

Astronomers using the Chandra X-Ray Observatory have discovered two stars that may be made of a new state of matter. The astronomers found one neutron star, 3C58, which was colder than expected had it been made of pure neutrons. Another star, RX J1856.5-3754, turned out to be only 11 km across, smaller than expected had it been composed of neutrons. Astronomers led by Jeremy Drake of the Harvard-Smithsonian Center for Astrophysics believe that the stars may be made not of neutrons but of quarks, the subatomic particles that combine to form neutrons and protons but are not otherwise found in nature. Astronomers acknowledged that one of the stars, RX J1856.5-3754, may in fact be an ordinary neutron star with a hot spot, but such a star would be expected to pulsate, and no such pulsations have yet to be observed.