September 20, 2007—A rare celestial body known as a magnetar shimmers in an explosion of x-rays in this artist's depiction.

The unusual object, about 15,000 light-years away in the constellation Sagittarius, is a small, fast-spinning neutron star that periodically shoots out huge cataclysms of x-ray emissions.

A new study has found that an outburst of radiation detected from the star in 2003 came from a spot below the star's surface only 2 miles (3.5 kilometers) across.

The magnetar is only about 9 miles (15 kilometers) across in total but contains about as much mass as the sun.

The study, conducted with the European Space Agency's XXM-Newton orbiting telescope, also found that the star has one of the most powerful magnetic fields in the universe—600 trillion times that of Earth's.

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