NASA'S WISE Scientists to Discuss Black Holes and Extreme Objects.-
WASHINGTON -- NASA will host a news teleconference at 1 p.m. EDT,
Wednesday, Aug. 29, to announce new discoveries from its Wide-field
Infrared Survey Explorer (WISE). The discoveries are related to the
distant universe, including supermassive black holes and rare galaxies.
The briefing participants are:
-- Daniel Stern, astronomer, NASA's Jet Propulsion Laboratory (JPL), Pasadena, Calif.
-- Peter Eisenhardt, WISE project scientist, JPL
-- Jingwen Wu, astronomer, JPL
-- Rachel Somerville, Downsbrough Chair in Astrophysics, Rutgers University
A link to the teleconference graphics will be available at the start of the event at:
The briefing participants are:
-- Daniel Stern, astronomer, NASA's Jet Propulsion Laboratory (JPL), Pasadena, Calif.
-- Peter Eisenhardt, WISE project scientist, JPL
-- Jingwen Wu, astronomer, JPL
-- Rachel Somerville, Downsbrough Chair in Astrophysics, Rutgers University
A link to the teleconference graphics will be available at the start of the event at:
For dial-in information, reporters should email their name, affiliation and telephone number to j.d.harrington@nasa.gov by noon Aug. 29.
For live audio of the teleconference, visit:
This artist's concept illustrates a dusty
planet-forming disk, similar to the one that vanished around the star
called TYC 8241 2652. Image credit: NASA/JPL-Caltech
› Larger view
Imagine if the rings of Saturn suddenly disappeared. Astronomers have
witnessed the equivalent around a young sun-like star called TYC 8241
2652. Enormous amounts of dust known to circle the star are unexpectedly
nowhere to be found.
"It's like the classic magician's trick: now you see it, now you don't.
Only in this case we're talking about enough dust to fill an inner solar
system and it really is gone!" said Carl Melis of the University of
California, San Diego, who led the new study appearing in the July 5
issue of the journal Nature.
A dusty disk around TYC 8241 2652 was first seen by the NASA Infrared
Astronomical Satellite (IRAS) in 1983, and continued to glow brightly
for 25 years. The dust was thought to be due to collisions between
forming planets, a normal part of planet formation. Like Earth, warm
dust absorbs the energy of visible starlight and reradiates that energy
as infrared, or heat, radiation.
The first strong indication of the disk's disappearance came from images
taken in January 2010 by NASA's Wide-field Infrared Survey Explorer, or
WISE. An infrared image obtained at the Gemini telescope in Chile on
May 1, 2012, confirmed that the dust has now been gone for
two-and-a-half years.
"Nothing like this has ever been seen in the many hundreds of stars that
astronomers have studied for dust rings," said co-author Ben Zuckerman
of UCLA, whose research is funded by NASA. "This disappearance is
remarkably fast even on a human time scale, much less an astronomical
scale. The dust disappearance at TYC 8241 2652 was so bizarre and so
quick, initially I figured that our observations must simply be wrong in
some strange way."
The astronomers have come up with a couple of possible solutions to the
mystery, but they say none are compelling. One possibility is that gas
produced in the impact that released the dust helped to quickly drag the
dust particles into the star and thus to their doom. In another
possibility, collisions of large rocks left over from an original major
impact provide a fresh infusion of dust particles into the disk, which
caused the dust grains to chip apart into smaller and smaller pieces.
The result is based upon multiple sets of observations of TYC 8241 2652
obtained with the Thermal-Region Camera Spectrograph on the Gemini South
telescope in Chile; IRAS; WISE; NASA's Infrared Telescope on Mauna Kea
in Hawaii; the European Space Agency's Herschel Space Telescope, in
which NASA plays an important role; and the Japanese/European Space
Agency AKARI infrared satellite.
Read the Gemini news release at
and the UCLA release at
NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages, and
operated, WISE for NASA's Science Mission Directorate. The spacecraft
was put into hibernation mode after it scanned the entire sky twice,
completing its main objectives. Edward Wright is the principal
investigator and is at UCLA. The mission was selected competitively
under NASA's Explorers Program managed by the agency's Goddard Space
Flight Center in Greenbelt, Md. The science instrument was built by the
Space Dynamics Laboratory in Logan, Utah. The spacecraft was built by
Ball Aerospace & Technologies Corp. in Boulder, Colo. Science
operations and data processing take place at the Infrared Processing and
Analysis Center at the California Institute of Technology in Pasadena.
Caltech manages JPL for NASA.
IRAS was executed jointly by the United States (NASA), the Netherlands
and the United Kingdom. The Infrared Telescope is operated and managed
for NASA by the University of Hawaii, located in Honolulu.
More information is online at
and
Whitney Clavin 818-354-4673
Jet Propulsion Laboratory, Pasadena, Calif.
Whitney.clavin@jpl.nasa.gov
2012-197
Jet Propulsion Laboratory, Pasadena, Calif.
Whitney.clavin@jpl.nasa.gov
2012-197
NASA
Guillermo Gonzalo Sánchez Achutegui
ayabaca@hotmail.com
ayabaca@gmail.com
ayabaca@yahoo.com
Inscríbete en el Foro del blog y participa : A Vuelo De Un Quinde - El Foro!
No hay comentarios:
Publicar un comentario