"It's as if the magnetar became a huge flaming torch and obliterated the dust around it, creating a massive cavity," says NASA's Chryssa Kouveliotou. "Nearby stars lit up the ring so that Spitzer [space telescope] could see it - a ring of fire marking the magnetar for eternity."
Click the image to see the story.
The ring, unlike anything ever seen before, formed in 1998 when the crusty iron surface of the magnetar cracked and erupted in a giant flare. The blast was so powerful, it ionized Earth's upper atmosphere and actually overloaded the instruments of several NASA spacecraft. (For more information about the event, see the 1998 Science@NASA story: Crusty Star Makes its Presence Felt.) Here's the APOD story with a chart of the gamma rays that hit us during that blast. Keep in mind that SGR 1900+14 lives about 20,000 light-years away from Earth. Whoah.
The eruption blew away a cloud surrounding the magnetar except for a ring of dust. The ring is flat and 7-by-3 light-years around.
The universe is full of wonder.