They are the known magnetars.
* SGR 1806-20, located 50,000 light-years from Earth on the far side of our Milky Way galaxy in the constellation of Sagittarius.
* SGR 1900+14, located 20,000 light-years away in the constellation Aquila. After a long period of low emissions (significant bursts only in 1979 and 1993) it became active in May-August 1998, and a burst detected on August 27, 1998 was of sufficient power to force NEAR Shoemaker to shut-down to prevent damage and to saturate instruments on BeppoSAX, WIND and RXTE. On May 29, 2008, NASA's Spitzer telescope discovered a ring of matter around this magnetar. It is thought that this ring formed in the 1998 burst. [14]
* 1E 1048.1-5937, located 9,000 light-years away in the constellation Carina. The original star, from which the magnetar formed, had a mass 30 to 40 times that of the Sun.