April 28, 2006

Erica Hupp/Grey Hautaluoma
Headquarters, Washington
(202) 358-1237/0668

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

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

RELEASE: 06-190

NASA LAUNCHES SATELLITES FOR WEATHER, CLIMATE, AIR-QUALITY STUDIES

Two NASA satellites were launched Friday from Vandenberg Air Force
Base, Calif., on missions to reveal the secrets of clouds and
aerosols, tiny particles suspended in the air.

CloudSat and CALIPSO - Cloud-Aerosol Lidar and Infrared Pathfinder
Satellite Observations - thundered skyward at approximately 6:02 a.m.
EDT atop a Boeing Delta II rocket. The two satellites will eventually
circle approximately 438 miles above Earth in a sun-synchronous polar
orbit, which means they will always cross the equator at the same
local time. Their technologies will enable scientists to study how
clouds and aerosols form, evolve and interact.

"Clouds are a critical but poorly understood element of our climate,"
said Graeme Stephens, CloudSat principal investigator and a professor
at Colorado State University, Fort Collins, Colo. "They shape the
energy distribution of our climate system and our planet's massive
water cycle, which delivers the freshwater we drink that sustains all
life."

"With the successful launch of CloudSat and CALIPSO we take a giant
step forward in our ability to study the global atmosphere," said
CALIPSO Principal Investigator David Winker of NASA's Langley
Research Center, Hampton, Va. "In the years to come, we expect these
missions to spark many new insights into the workings of Earth's
climate and improve our abilities to forecast weather and predict
climate change."

Each spacecraft will transmit pulses of energy and measure the portion
of the pulses scattered back to the satellite. 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. CALIPSO's polarization lidar can
detect aerosol particles and distinguish between aerosol and cloud
particles. Lidar, similar in principle to radar, uses reflected light
to determine the characteristics of the target area.

Sixty-two minutes after liftoff, CALIPSO separated from the rocket's
second stage. CloudSat followed 35 minutes later. Ground controllers
successfully acquired signals from both spacecraft, and initial
telemetry reports show both in excellent health. Over the next six
weeks, system and instrument checks will be performed, and the
satellites will maneuver into their final orbits.

The satellites will fly in formation as members of NASA's "A-Train"
constellation, which also includes NASA's Aqua and Aura satellites
and a French satellite known as PARASOL, for Polarization and
Anisotropy of Reflectances for Atmospheric Sciences coupled with
Observations from a Lidar. The satellite data will be more useful
when combined, providing insights into the global distribution and
evolution of clouds to improve weather forecasting and climate
prediction. For more information about CloudSat and CALIPSO, visit:

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

CloudSat is managed by NASA's Jet Propulsion Laboratory, Pasadena,
Calif. JPL developed the radar instrument with hardware contributions
from the Canadian Space Agency. Colorado State provides scientific
leadership and science data processing and distribution. Ball
Aerospace and Technologies Corp., Boulder, Colo., designed and built
the spacecraft. The U.S. Air Force and Department of Energy
contributed resources. U.S. and international universities and
research centers support the mission science team.

CALIPSO is collaboration between NASA and France's Centre National
d'Etudes Spatiales (CNES). Langley is leading the CALIPSO mission and
providing overall project management, systems engineering, and
payload mission operations. NASA's Goddard Space Flight Center,
Greenbelt, Md., provides support for system engineering, project and
program management. CNES is providing a PROTEUS spacecraft developed
by Alcatel Space, a radiometer instrument, and spacecraft mission
operations. Hampton University, Hampton, Va., is providing scientific
contributions and managing the outreach program. Ball Aerospace
developed the lidar and on-board visible camera.

NASA's Launch Services Program at Kennedy Space Center, Fla. procured
the mission's launch and provided the management for the mission's
launch service. For NASA and agency information, visit:

http://www.nasa.gov/home


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