MEDIA RELATIONS OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIF. 91109 TELEPHONE (818) 354-5011
http://www.jpl.nasa.gov

Alan Buis (818) 354-0474 (CloudSat)
Jet Propulsion Laboratory, Pasadena, Calif.

Erica Hupp/Dolores Beasley (202) 358-1237/1753
NASA Headquarters, Washington

Chris Rink (757) 864-6786 (Calipso)
Langley Research Center, Hampton, Va.

News Release: 2005-149
September 15, 2005

NASA Will Reveal Secrets of Clouds and Aerosols

Two NASA satellites, planned for launch no earlier than
Oct. 26, will give us a unique view of Earth's atmosphere.
CloudSat and Cloud-Aerosol Lidar and Infrared Pathfinder
Satellite Observations (Calipso) are undergoing final
preparations for launch from Vandenberg Air Force Base,
Calif.

CloudSat and Calipso will provide a new, 3-D perspective
on Earth's clouds and airborne particles called aerosols.
The satellites will answer questions about how clouds and
aerosols form, evolve and affect water supply, climate,
weather and air quality.

CloudSat and Calipso employ revolutionary tools that will
probe Earth's atmosphere. Each spacecraft carries an
"active" instrument that transmits pulses of energy and
measures the portion of the pulses scattered back to the
instrument.

CloudSat's cloud-profiling radar is more than 1,000 times
more sensitive than typical weather radar. It can detect
clouds and distinguish between cloud particles and
precipitation. "The new information from CloudSat will
answer basic questions about how rain and snow are
produced by clouds, how rain and snow are distributed
worldwide and how clouds affect the Earth's climate,"
said Dr. Graeme Stephens, CloudSat principal investigator
at Colorado State University, Fort Collins, Colo.

Calipso's polarization lidar instrument can detect aerosol
particles and can distinguish between aerosol and cloud
particles. "With the high resolution observation that
Calipso will provide, we will get a better understanding
of aerosol transport and how our climate system works,"
said Dr. David Winker, Calipso principal investigator
at NASA's Langley Research Center, Hampton, Va.

The satellites will be launched into a 705-kilometer
(438-mile) circular, sun-synchronous polar orbit, where
they will fly in formation just 15 seconds apart as
members of NASA's "A- Train" constellation with three
other Earth Observing System satellites. The A-Train
includes NASA's Aqua and Aura satellites and France's
Polarization and Anisotropy of Reflectances for
Atmospheric Sciences coupled with observations from a
Lidar satellite.

The usefulness of data from CloudSat, Calipso and the
other A-Train satellites will be much greater when
combined. The combined set of measurements will
provide new insight into the global distribution and
evolution of clouds that will lead to improvements in
weather forecasting and climate prediction.

CloudSat is managed by NASA's Jet Propulsion Laboratory,
Pasadena, Calif. The radar instrument was developed at
JPL, with hardware contributions from the Canadian Space
Agency. Colorado State University provides scientific
leadership and science data processing and distribution.

Other contributions include resources from the U.S.
Air Force and the U.S. Department of Energy. Ball
Aerospace and Technologies Corp. designed and built
the spacecraft. A host of U.S. and international
universities and research centers provides support to
the science team. Some of these activities are
contributed as partnerships with the project.

Calipso was developed through collaboration between
NASA and the French Space Agency, Centre National
d'Etudes Spatiales. NASA's Langley Research Center
leads the Calipso mission and provides science team
leadership, systems engineering, payload mission
operations, and validation, processing and archiving
of data. Langley also developed the lidar instrument
in collaboration with the Ball Aerospace and
Technologies Corp., which developed the onboard
visible camera.

NASA's Goddard Space Flight Center, Greenbelt, Md.,
provides project management, system engineering
support and overall program management. Centre
National d'Etudes Spatiales provides a Proteus
spacecraft developed by Alcatel, the imaging
infrared radiometer, payload-to-spacecraft
integration and spacecraft mission operations.
The Institut Pierre Simon Laplace in Paris
provides the imaging infrared radiometer science
oversight, data validation and archival. Hampton
University provides scientific contributions and
manages the outreach program.

For more information on CloudSat and Calipso on
the Internet, please visit

http://www.nasa.gov/cloudsat

and

http://www.nasa.gov/calipso .

JPL is managed for NASA by the California
Institute of Technology in Pasadena.

-end-