Giant planet's start seen swirling around star

How do jumbo planets such as Jupiter form? Astronomers may have caught one in a nearby solar system being born, offering an answer.

A pair of dusty filaments stretch more than 7.4 billion miles across the length of the solar system of nearby star HD14252, feeding a young planet's growth in a manner never seen before, report radio astronomers led by Simon Casassus of Chile's Universidad de Chile in Santiago.

The team used Chile's new Atacama Large Millimeter/submillimeter Array (ALMA) to take a close look at the dust disks swirling around the star. The find supports a theory that instabilities in such disks surrounding young stars build up to grow giant planets in a snowballing fashion.

"Astronomers and theorists have been waiting for decades for ALMA to be built and begin operations, and this early discovery shows that the wait has been well worthwhile," says planetary scientist Alan Boss, author of The Crowded Universe: The Race to Find Life Beyond Earth. "This is great stuff!" he says, by e-mail.

The Nature journal study reports a Jupiter-size planet is likely forming about 90 times farther away from the star than Earth's orbital distance from the sun. Boss suggests that other giant planets have likely already formed around the star, clearing a central dust-free ring around HD 14252.