ALMA Sees Ring Of Icy Debris Around A Young Star System 25 Light-Years Away

[Judi Lynn]

BY HIMANSHU GOENKA @HIMGOJOURNO ON 05/19/17 AT 4:01 AM


A young star system about 25 light-years away from Earth has a well-defined band of icy rubble and gas around it, which is likely a result of exocomets colliding into each other near the edges of the system. That band, in all its striking glory, was imaged along with the planetary system using the Atacama Large Millimeter/submillimeter Array (ALMA) of radio telescopes in Chile.

ALMA had first observed dusty debris surrounding the young star Fomalhaut in 2012, when the telescope was still being built. It had seen only half the ring that time, but the images released Thursday by the National Radio Astronomy Observatory are “the first complete millimeter-wavelength image of the ring of dusty debris” around the star.

Fomalhaut, whose mass is about twice that of the sun, and the planets that orbit it are only about a tenth as old as our solar system, having been formed around about 440 million years ago. The system is one of the score or so whose planets have been imaged directly, instead of being inferred through indirect means. The band of icy dust seen in the ALMA image is about 20 billion kilometers (about 12.5 billion miles) away from the star at its center, and 2 billion kilometers wide across its circular length. It is likely produced as a result of the gravitational influence of the planets in the system.

“ALMA has given us this staggeringly clear image of a fully formed debris disk. We can finally see the well-defined shape of the disk, which may tell us a great deal about the underlying planetary system responsible for its highly distinctive appearance,” Meredith MacGregor, an astronomer at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts, and lead author on one of two papers accepted for publication in the Astrophysical Journal describing these observations, said in a statement accompanying the images.

More:
http://www.ibtimes.com/alma-sees-ring-icy-debris-around-young-star-system-25-light-years-away-2541083

[Bernardo de La Paz]

1. Fascinating. Thanks. . nt