By Ron Cowen
The neutron star XTE J1739-285 is the burned-out remains of what was once a brilliant celestial body. Now, astronomers have evidence that it’s the fastest-spinning stellar corpse known.
X-ray observations indicate that the neutron star spins 1,122 times a second, about 30 percent faster than the previous record holder, report Phil Kaaret of the University of Iowa in Iowa City and his colleagues in the March 10 Astrophysical Journal Letters.
NASA’s Rossi X-ray Timing Explorer discovered the neutron star in 1999 when it emitted bursts of X rays. After several years of quiescence, it began sending out new bursts in 2005. Studies of other neutron stars had shown that variations in the brightness of X-ray bursts indicate the stars’ rotation rates.