Young Stars Surrounded by "Hula Hoops" of Debris Discovered

Using NASA's Spitzer Space Telescope, astronomers have spotted a young star system that appears to be two developing stars surrounded by disks of star-formation residue. The stars, those who discovered say, are caught in a game of cosmic peek-a-boo while a third orbits at the periphery.

Called YLW 16A, the system "blinks" every 93 days as the two inner stars whirl around each other, periodically popping out from the disk that girds them like a hula hoop. Moreover, this disk, the scientists determined, is misaligned -- probably due to the disruptive gravitation of the third star -- and is likely to go on to spawn planets and other celestial bodies that make up a solar system.

As the fourth example of a star system known to blink in such a manner, and the second spotted in the same star-forming region Rho Ophiuchus, YLW 16A is evidence these systems might be more common than once thought, the researchers explain in their analysis of the finding.

Furthermore, blinking star systems with warped disks offer scientists a way to study how planets form in these environments. In a binary star system, it's possible for the planets to orbit one or both of the stars -- much like the famous fictional planet Tatooine in "Star Wars" with its double sunsets. Such worlds are referred to as circumbinary planets, and because astronomers can record how light is absorbed by planet-forming disks during the bright and faint phases of blinking stellar systems, they offer a unique look into the information regarding the materials that comprise the disk.

"These blinking systems offer natural probes of the binary and circumbinary planet formation process," said Peter Plavchan, a scientist at the NASA Exoplanet Science Institute and Infrared Processing and Analysis Center at the California Institute of Technology, Pasadena, Calif., and lead author of a paper.

Spitzer was aided in its study of YLW 16A by the ground-based 2MASS survey, as well as from the NACO instrument at the European Southern Observatory's Very Large Telescope in Chile.