Glow-in-the-dark stars are a magical way to decorate a bedroom, creating shining constellations on ceilings or walls. Please look at the time stamp on the story to see when it was last updated. That's how we'll learn just where you are.This is an archived article and the information in the article may be outdated. At least until the next quake.Īstronomers suspect that magnetars lose their punch as time passes, but Swift J195509+261406 provides the missing link between objects exhibiting regular activity and those that have settled into retirement - and invisibility. Once the star’s crust and magnetic field settle down, the star goes dark and disappears from our view. This "starquake" releases pent-up magnetic energy, which creates bursts of light and radiation. Every now and then, the magnetar’s rigid crust snaps under the strain. So what happened last year? Why did this previously unseen star begin behaving so badly? And why did it stop?Ĭombine a magnetar's pumped-up magnetic field with its rapid spin, and sooner or later something has to give. We just don’t see them because they’re quiet most of the time. Only about a dozen magnetars are known, but scientists suspect our galaxy contains many more. Sometimes, those magnetic fields are super strong - more than 100 times the strength of typical neutron stars.Īstronomers put these magnetic monsters in their own class: magnetars. "Magnetars remain quiet for decades."Īlthough measuring only about 12 miles across - about the size of a city - neutron stars have the strongest magnetic fields in the cosmos. "We are dealing with an object that was hibernating for decades before entering a brief activity period," explains Alberto J. 25 issue of the science journal Nature, a team of 42 scientists concludes that Swift J195509+261406 is a special type of neutron star called a magnetar. "The observatory is an astronomical robot built for gamma-ray burst studies, but it can also quickly point at other bizarre objects with bright flares."Īstronomers think the object was a neutron star - the crushed innards of a massive star that long ago exploded as a supernova - about 15,000 light-years away. "I love it when Swift enables a discovery like this," says Neil Gehrels, the mission's lead scientist at NASA Goddard Space Flight Center in Greenbelt, Md. Not once, not twice - but 40 times! Eleven days later, it flashed again, this time at infrared wavelengths. (Well, they had to call it something!)ĭuring the next three days, the object brightened and faded in visible light. Because Swift found an X-ray glow coming from this point, astronomers cataloged the object as "Swift J195509+261406," after its position in the sky and the discovering satellite. Within a minute, robotic telescopes turned to a spot in the constellation Vulpecula. Swift immediately reported the event’s position to astronomers all over the world. But this high-energy flash wasn't a gamma-ray burst - the birth cry of a black hole far across the universe. That’s when a spike of gamma-rays lasting less than five seconds washed over NASA's Swift satellite. Now, astronomers are reporting on a strange case where one of the littlest of stars "twinkled" with gamma rays, X-rays, and light - and then vanished. "Twinkle, twinkle little star" goes the nursery rhyme. Credit: NASA/Swift/Sonoma State University/A. A starquake is probably what triggered the object's 40 optical flares. This illustration shows a flare from magnetar Swift J195509+261406.
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