[meteorite-list] WISE Mission Assembled and Preparing for Launch

[Ron Baalke]

http://www.jpl.nasa.gov/news/features.cfm?feature=2183  

WISE Mission Assembled and Preparing for Launch
Jet Propulsion Laboratory
June 10, 2009

PASADENA, Calif. -- NASA's Wide-field Infrared Survey Explorer, or WISE,
has been assembled and is undergoing final preparations for a planned
Nov. 1 launch from Vandenberg Air Force Base, Calif.

The mission will survey the entire sky at infrared wavelengths, creating
a cosmic clearinghouse of hundreds of millions of objects -- everything
from the most luminous galaxies, to the nearest stars, to dark and
potentially hazardous asteroids. The survey will be the most detailed to
date in infrared light, with a sensitivity hundreds of times better than
that of its predecessor, the Infrared Astronomical Satellite.

"Most of the sky has never been imaged at these infrared wavelengths
with this kind of sensitivity," said Edward Wright, the mission's
principal investigator at UCLA. "We are sure to find many surprises."

On May 17, the mission's science instrument was delivered to Ball
Aerospace & Technologies Corp. in Boulder, Colo., where it was attached
to the spacecraft, built by Ball. The assembled unit was then blasted by
sound to simulate the effects of launch. Tests for electronic "noise" in
the detectors will be performed next.

The science instrument is a 40-centimeter (16-inch) telescope with four
infrared cameras. A cryostat, or cooler, uses frozen hydrogen to chill
the sensitive megapixel infrared detectors down to seven Kelvin (minus
447 degrees Fahrenheit). The instrument was built by Space Dynamics
Laboratory in Logan, Utah.

Among expected finds from WISE are hundreds of thousands of asteroids in
our solar system's asteroid belt, and hundreds of additional asteroids
that come near Earth. Many asteroids have gone undetected because they
don't reflect much visible light, but their heat makes them glow in
infrared light that WISE can see. By cataloguing the objects, the
mission will provide better estimates of their sizes, a critical step
for assessing the risk associated with those that might impact Earth.

"We know that asteroids occasionally hit Earth, and we'd like to have a
better idea of how many there are and their sizes," said Amy Mainzer of
NASA's Jet Propulsion Laboratory, Pasadena, Calif., the mission's deputy
project scientist. "Whether they are dark or shiny, they all emit
infrared light. They can't hide from WISE."

The mission is also expected to find the coldest stars -- dim orbs
called brown dwarfs that are too small to have ignited like our sun.
Brown dwarfs are littered throughout our galaxy, but because they are so
cool, they are often too faint to see in visible light. The infrared
detectors on WISE will pick up the glow of roughly 1,000 brown dwarfs in
our galaxy, including those coldest and closest to our solar system. In
fact, astronomers say the mission could find a brown dwarf closer to us
than the nearest known star, Proxima Centauri, located approximately 4
light-years away.

"We've been learning that brown dwarfs may have planets, so it's
possible we'll find the closest planetary systems," said Peter
Eisenhardt, the mission's project scientist at JPL. "We should also find
many hundreds of brown dwarfs colder than 480 degrees Celsius (900
degrees Fahrenheit), a group that as of now has only nine known members."

In addition, the survey will reveal the universe's most luminous
galaxies seen long ago in the dusty throes of their formation, disks of
planet-forming material around stars, and other cosmic goodies. The
observations will guide other infrared telescopes to the most
interesting objects for follow-up studies. For example, NASA's Spitzer
Space Telescope, the Herschel observatory just launched by ESA with
significant NASA participation, and NASA's upcoming James Webb Space
Telescope will direct their gaze at objects uncovered by WISE.

WISE will lift off from Vandenberg aboard a United Launch Alliance Delta
II rocket. It will orbit Earth, mapping the entire sky in six months
after a one-month checkout period. Its frozen hydrogen is expected to
last several months longer, allowing WISE to map much of the sky a
second time and see what has changed.

JPL manages the Wide-field Infrared Survey Explorer for NASA's Science
Mission Directorate. The mission's principal investigator, Edward
Wright, is at UCLA. The mission was developed under NASA's Explorer
Program managed by the Goddard Space Flight Center, Greenbelt, Md. The
science instrument was built by the Space Dynamics Laboratory and the
spacecraft was built by Ball Aerospace & Technologies Corp. Science
operations and data processing will 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 http://wise.ssl.berkeley.edu/mission.html .

The Infrared Astronomical Satellite, launched in 1983, was a joint
mission between NASA, the United Kingdom and the Netherlands.

Media contact: Whitney Clavin/JPL
818-354-4673