Hi My Friends: A VUELO DE UN QUINDE EL BLOG., NASA's Wide-field Infrared Survey Explorer (WISE) mission has led to a
bonanza of newfound supermassive black holes and extreme galaxies called
hot DOGs, or dust-obscured galaxies.
With its all-sky infrared survey, NASA's
Wide-field Infrared Survey Explorer, or WISE, has identified millions of
quasar candidates. Image credit: NASA/JPL-Caltech/UCLA
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A Sky Chock-Full of Black Holes
With its all-sky infrared survey, NASA's Wide-field Infrared Survey Explorer, or WISE, has identified millions of quasar candidates. Quasars are supermassive black holes with masses millions to billions times greater than our sun. The black holes "feed" off surrounding gas and dust, pulling the material onto them. As the material falls in on the black hole, it becomes extremely hot and extremely bright. This image zooms in on one small region of the WISE sky, covering an area about three times larger than the moon. The WISE quasar candidates are highlighted with yellow circles.Image credit: NASA/JPL-Caltech/UCLA
PASADENA, Calif. -- NASA's Wide-field Infrared Survey Explorer (WISE)
mission has led to a bonanza of newfound supermassive black holes and
extreme galaxies called hot DOGs, or dust-obscured galaxies.
Images from the telescope have revealed millions of dusty black hole
candidates across the universe and about 1,000 even dustier objects
thought to be among the brightest galaxies ever found. These powerful
galaxies, which burn brightly with infrared light, are nicknamed hot
DOGs.
"WISE has exposed a menagerie of hidden objects," said Hashima Hasan,
WISE program scientist at NASA Headquarters in Washington. "We've found
an asteroid dancing ahead of Earth in its orbit, the coldest star-like
orbs known and now, supermassive black holes and galaxies hiding behind
cloaks of dust."
WISE scanned the whole sky twice in infrared light, completing its
survey in early 2011. Like night-vision goggles probing the dark, the
telescope captured millions of images of the sky. All the data from the
mission have been released publicly, allowing astronomers to dig in and
make new discoveries.
The latest findings are helping astronomers better understand how
galaxies and the behemoth black holes at their centers grow and evolve
together. For example, the giant black hole at the center of our Milky
Way galaxy, called Sagittarius A*, has 4 million times the mass of our
sun and has gone through periodic feeding frenzies where material falls
towards the black hole, heats up and irradiates its surroundings. Bigger
central black holes, up to a billion times the mass of our sun, may
even shut down star formation in galaxies.
In one study, astronomers used WISE to identify about 2.5 million
actively feeding supermassive black holes across the full sky,
stretching back to distances more than 10 billion light-years away.
About two-thirds of these objects never had been detected before because
dust blocks their visible light. WISE easily sees these monsters
because their powerful, accreting black holes warm the dust, causing it
to glow in infrared light.
"We've got the black holes cornered," said Daniel Stern of NASA's Jet
Propulsion Laboratory, Pasadena, Calif., lead author of the WISE black
hole study and project scientist for another NASA black-hole mission,
the Nuclear Spectroscopic Telescope Array (NuSTAR). "WISE is finding
them across the full sky, while NuSTAR is giving us an entirely new look
at their high-energy X-ray light and learning what makes them tick."
In two other WISE papers, researchers report finding what are among the
brightest galaxies known, one of the main goals of the mission. So far,
they have identified about 1,000 candidates.
These extreme objects can pour out more than 100 trillion times as much
light as our sun. They are so dusty, however, that they appear only in
the longest wavelengths of infrared light captured by WISE. NASA's
Spitzer Space Telescope followed up on the discoveries in more detail
and helped show that, in addition to hosting supermassive black holes
feverishly snacking on gas and dust, these DOGs are busy churning out
new stars.
"These dusty, cataclysmically forming galaxies are so rare WISE had to
scan the entire sky to find them," said Peter Eisenhardt, lead author of
the paper on the first of these bright, dusty galaxies, and project
scientist for WISE at JPL. "We are also seeing evidence that these
record setters may have formed their black holes before the bulk of
their stars. The 'eggs' may have come before the 'chickens.'"
More than 100 of these objects, located about 10 billion light-years
away, have been confirmed using the W.M. Keck Observatory on Mauna Kea,
Hawaii, as well as the Gemini Observatory in Chile, Palomar's 200-inch
Hale telescope near San Diego, and the Multiple Mirror Telescope
Observatory near Tucson, Ariz.
The WISE observations, combined with data at even longer infrared
wavelengths from Caltech's Submillimeter Observatory atop Mauna Kea,
revealed that these extreme galaxies are more than twice as hot as other
infrared-bright galaxies. One theory is their dust is being heated by
an extremely powerful burst of activity from the supermassive black
hole.
"We may be seeing a new, rare phase in the evolution of galaxies," said
Jingwen Wu of JPL, lead author of the study on the submillimeter
observations. All three papers are being published in the Astrophysical
Journal.
The three technical journal articles, including PDFs, can be found at
and
JPL manages and operates WISE for NASA's Science Mission Directorate,
Washington. The principal investigator, Edward Wright, is at UCLA. The
mission was competitively selected under NASA's Explorers Program
managed by the Goddard Space Flight Center, Greenbelt, Md. The science
instrument was built by the Space Dynamics Laboratory, Logan, Utah, and
the spacecraft was built by Ball Aerospace & Technologies Corp.,
Boulder, Colo. Science operations and data processing and archiving take
place at the Infrared Processing and Analysis Center at the California
Institute of Technology in Pasadena. Caltech manages JPL for NASA.
More information is online at
and
NASA
Guillermo Gonzalo Sánchez Achutegui
ayabaca@gmail.com
ayabaca@hotmail.com
ayabaca@yahoo.com
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