A giant dust cloud hundreds of light years from Earth may be hiding the birth of a new planet in distant orbit around a dying star, which would be a much different arrangement than within our own solar system.

The finding, if confirmed, would help demonstrate that planets can form around stars of all ages. And it may suggest that planets populate the universe in greater numbers than astronomers had realized."I take a look at this and I say, `Hmm, planet formation is going on all over the place. Maybe it's under our noses!' " said astronomer Susan Kleinmann at the University of Massachusetts.

The mysterious cloud, which is larger than our whole solar system, was identified by astronomers Michael Jura and Jean Turner at the University of California at Los Angeles. The discovery was published this week in the science journal Nature.

Planets are believed to form when wheeling clouds of dust and rock become compacted under the force of gravity. The astronomers located the cloud by measuring the invisible electromagnetic radiation emitted by the dust grains.

Scientists are only now beginning to identify planets outside our solar system. They have found as many as 12 planetary systems in the universe. A few of them are near pulsars, or older stars that give off pulses of radio waves. But most are associated with younger stars.

The mystery dust cloud, with an estimated overall mass equal to that of Jupiter, floats near a star known as HD44179, about 1,100 light-years from Earth.