In this artist's impression, a disk of dusty
material leftover from star formation girds two young stars like a hula
hoop. As the two stars whirl around each other, they periodically peek
out from the disk, making the system appear to "blink" every 93 days.
Image credit: NASA/JPL-Caltech. › Full image and caption
Astronomers using NASA's Spitzer Space Telescope have spotted a young
stellar system that "blinks" every 93 days. Called YLW 16A, the system
likely consists of three developing stars, two of which are surrounded
by a disk of material left over from the star-formation process.
As the two inner stars whirl around each other, they periodically peek
out from the disk that girds them like a hula hoop. The hoop itself
appears to be misaligned from the central star pair, probably due to the
disrupting gravitational presence of the third star orbiting at the
periphery of the system. The whole system cycles through bright and
faint phases, with the central stars playing a sort of cosmic peek-a-boo
as the tilted disk twirls around them. It is believed that this disk
should go on to spawn planets and the other celestial bodies that make
up a solar system.
Spitzer observed infrared light from YLW 16A, emitted by the warmed gas
and dust in the disk that still swathes the young stars. Other
observations came from the ground-based 2MASS survey, as well as from
the NACO instrument at the European Southern Observatory's Very Large
Telescope in Chile.
YLW 16A is the fourth example of a star system known to blink in such a
manner, and the second in the same star-forming region Rho Ophiuchus.
The finding suggests that these systems might be more common than once
thought. Blinking star systems with warped disks offer scientists a way
to study how planets form in these environments. The planets can orbit
one or both of the stars in the binary star system. The famous science
fictional planet Tatooine in "Star Wars" orbits two stars, hence its
double sunsets. Such worlds are referred to as circumbinary planets.
Astronomers can record how light is absorbed by planet-forming disks
during the bright and faint phases of blinking stellar systems, which in
turn reveals information about 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 new paper accepted for publication in
Astronomy & Astrophysics.
NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Spitzer
Space Telescope mission for NASA's Science Mission Directorate,
Washington. Science operations are conducted at the Spitzer Science
Center at Caltech. Data are archived at the Infrared Science Archive
housed at the Infrared Processing and Analysis Center. Caltech manages
JPL for NASA. For more information about Spitzer, visit http://spitzer.caltech.edu and http://www.nasa.gov/spitzer .
Written by Adam Hadhazy
Contact:
Whitney Clavin 818-354-4673
Jet Propulsion Laboratory, Pasadena, Calif.
whitney.clavin@jpl.nasa.gov