Look out universe, theres a big blob on the prowl.

Yes, its true: a giant magnetic blob, the first of its kind ever detected, has been found surrounding an entire galaxy. The galaxy, cataloged as M 82, is also known as the "Cigar." Scientists dont yet know what to make of the blob, which is composed of magnetic field lines, but theyre calling it one of the most intriguing astronomical mysteries to pop up in a long time.

"To my knowledge, this is the first time something like this has been found," said Jane Greaves, lead author of an April 13 Nature article describing the discovery. "We were very surprised [to find it]!"

The blob, which lies some 10 million light-years from Earth, was discovered with the help of the SCUBA camera on the James Clerk Maxwell Telescope in Hawaii. The camera, acting like a huge pair of polarizing sunglasses, detected the blob by filtering light from galactic dust particles and measuring their orientation.

Greaves and her colleges "saw" the huge magnetic blob when they discovered that many of the galaxys dust particles were lined up around local magnetic field lines, which surround M 82 like the magnetic lines around an ordinary magnet.

Experts still havent a clue what could have caused the Cigar galaxy to generate such a large magnetic field. Some speculate that it might have something to do with galactic winds that may have blown normal magnetic fields lying in the galaxys main plane to its outer limits. But then again, it might be something completely different. "This is one of the great enigmas in astronomy," explained Greaves.

Scientists are also curious to find whether such a blob is the norm for all galaxies, or if theres something special about M 82 that prompted it to inherit or create its own magnetic shell. Astronomers studying this case will soon begin a survey of other nearby galactic objects to see if they too are surrounded by magnetic field lines. "Well probably look at a few galaxies that are reasonably close," said Greaves.

While theres no evidence yet, speculation has arisen about whether or not our own Milky Way galaxy generates a similar magnetic shell on its outskirts. "We do know there are some giant lobes of radio emission coming out of the galactic center," said Greaves. It might be possible, she argues, to employ methods similar to those used to discover the magnetic blob around M 82 to find one that may envelop the Milky Way.