Last year,the Rossi X-ray Timing Explorer (RXTE) spacecraft was aimed at a pulsar named PSR J1846-0258 some 20,000 light-years away in the constellation Aquila when the star suddenly erupted in a blast of x-rays.
The display, which propagated as stripes across the stellar disc,is reported online in Science, by Fotis Gavriil of NASA's Goddard Space Flight Center. He suggests PSR J1846-0258 may be a magnetar in the making---a neutron star with an enormously powerful magnetic field. Only a dozen or so have been discovered, routinely emitting energetic x and gamma rays.
"The bursts were completely unexpected," Fotis told Science, Because the young-- roughly millennium old-- pulsar's magnetic field strength is low his colleagues suspect it is still evolving. He says the discovery raises important questions-- Do pulsars behave like magnetars only periodically and then revert? Did all magnetars originate as pulsars?