An enormous eruption has found its way to Earth after travelling for many thousands of years across space. Studying this blast with ESA’s XMM-Newton and Integral space observatories, astronomers have discovered a dead star belonging to a rare group: the magnetars. X-Rays from the giant outburst arrived on Earth on 22 August 2008, and triggered an automatic sensor on the NASA-led, international Swift satellite. Just twelve hours later, XMM-Newton zeroed in and began to collect the radiation, allowing the most detailed spectral study of the decay of a magnetar outburst. The outburst lasted for more than four months, during which time hundreds of smaller bursts were measured.
Magnetars are the most intensely magnetised objects in the Universe. Their magnetic fields are some 10 000 million times stronger than Earth’s. If a magnetar were to magically appear at half the Moon’s distance from Earth, its magnetic field would wipe the details off every credit card on Earth.
This particular magnetar, known as SGR 0501+4516, is estimated to lie about 15 000 light-years away, and was undiscovered until its outburst gave it away. An outburst takes place when the unstable configuration of the magnetic field pulls the magnetar’s crust, allowing matter to spew outwards in an exotic volcanic eruption. This matter tangles with the magnetic field which itself can change its configuration, releasing more energy.
Adapted from material provided by European Space Agency
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