Scientists Detect Mysterious Oddball Star

P A S A D E N A, Calif., Sept. 1 -- Scientists using theHubble Space Telescope have found a mysterious object that may bea sun-like star in its death throes, or a pair of aging starsmasquerading as a single youngster.

In any case, officials at the Jet Propulsion Lab in Pasadenasaid on Thursday, it defies all known classifications.

The object, called He2-90, looks like a young,dust-enshrouded star with narrow jets of material resemblingstrings of beads emanating from it, the scientists said.

Each jet contains at least six bright clumps of gas speedingalong at rates of at least 375,000 mph. These clumps are ejected into space aboutevery 100 years. Young stars behave in a similar way.

Hubble astronomers believe the object is actually two agingstars masquerading as a single youngster. One may be a bloatedred giant star shedding matter from its outer layers. Thismatter is then captured by gravity in a rotating accretion diskaround a compact partner, most likely a young white dwarf, thecollapsed remnant of a sun-like star, JPL scientists said.

Resembles Our Solar System

“It looks like what you usually see with young stars, abipolar nebulae with two bright blobs of light separated by adark lane,” JPL astronomer Raghvendra Sahai said. “The twosides are flared like saucers so they can reflect starlight,and the dark lane is actually a disc-like structure seenedge-on.”

Sahai said the “jets” are emanating at right angles fromthe two “saucers,” resembling an axle for two tires. Thedisc-like structure is a mixture of matter and gases, thecenter of which is a growing young star, he said. Our solarsystem grew in similar fashion, he said.

Deep space images show the “jets” are 100,000 times longerthan the distance from the Earth to the sun, which is 93 millionmiles.

The oddball star was discovered during a survey of planetarynebulae. The images were taken Sept. 28 last year with Hubble’swide field planetary camera 2.