NASA Astronomy Picture of the Day Collection

SGR 1900 14: Magnetar

On August 27th an intense flash [ http://cfa-www.harv…] of X-rays and gamma-rays [ http://cossc.gsfc.n…] swept through our Solar System. Five spacecraft of the Third InterPlanetary gamma-ray burst Network [ http://ssl.berkeley…], Ulysses [ http://helio.estec.…], WIND [ http://heasarc.gsfc…], RXTE [ http://heasarc.gsfc…], NEAR [ http://sd-www.jhuap…], and BeppoSAX [ http://heasarc.gsfc…], recorded the high energy signal -- a signal so strong that it saturated detectors on WIND and RXTE and triggered the safety mode automatic shut-off of the NEAR gamma-ray instrument! As plotted here, the count rate for the Ulysses detector abruptly spiked to a high level and then slowly tailed off showing smaller peaks roughly every 5 seconds. The signal and location provided by these spacecraft observations leads researchers to identify the source as a dramatic flare-up from one of only four previously known "Soft Gamma Repeaters" [ http://science.msfc…]. These exotic sources of gamma-rays are believed [ http://science.msfc…] to be highly magnetized spinning neutron stars called Magnetars [ http://antwrp.gsfc.…]. Imaginatively cataloged as SGR 1900 14 [ http://xxx.lanl.gov…], this magnetar is estimated to have been born in a supernova explosion [ http://antwrp.gsfc.…] about 1,500 years ago and to have a magnetic field 500,000,000,000,000 times stronger than Earth's [ http://www-spof.gsf…].

Kevin Hurley [ mailto:khurley@sunsp ot.ssl.berkeley.edu ] (Space Sciences Laboratory [ http://ssl.berkeley…])

neutron star

magnetar

soft gamma repeater

Goddard Space Flight Center (GSFC)

Washington, D.C.

Marshall Space Flight Center (MSFC)

Earth

Ulysses

SAX

http://antwrp.gsfc.…

SPD-APOD-ap980903