NASA's two newest Earth-observation satellites, CALIPSO and CloudSAT, are scheduled to be launched into polar orbit from California's Vandenberg Air Force Base on April 21, 2006 at 6:02 a.m. EDT. Launch coverage will begin on NASA TV's Public and Media channels and on the web 90 minutes before, at 4:30 a.m. EDT.

A pre-launch webcast will occur on April 19, 2006 at 7:30 p.m. EDT and can be accessed at http://www.nasa.gov/mission_pages/cloudsat/main/index.html and http://www.nasa.gov/mission_pages/calipso/launch/event-cloud-calipso.html.
Please join in the excitement by participating in the missions'
webcast. The public can submit questions by 11:00 a.m. EDT on April 17, 2006.

CALIPSO, or Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation, will provide new insight into the role that clouds and atmospheric aerosols (airborne particles) play in regulating Earth's weather, climate and air quality. CALIPSO combines an active lidar instrument with passive infrared and visible imagers to probe the vertical structure and properties of thin clouds and aerosols over the globe.

The CALIPSO satellite is sharing a launch vehicle, a Delta II rocket, with the cloud profiling radar system on the CloudSat satellite. CALIPSO and CloudSat are highly complementary and together will provide new, never-before-seen 3-D perspectives of how clouds and aerosols form, evolve, and affect weather and climate. CALIPSO and CloudSat will fly in formation with three other satellites in the A-train constellation to enable an even greater understanding of our climate system from the broad array of sensors on these other spacecraft.

CALIPSO is a joint U.S. (NASA) and French (Centre National d'Etudes Spatiales, or CNES) satellite mission with an expected 3 year lifetime.
NASA's Langley Research Center, Hampton, VA, leads the Calipso mission.

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.

Fact sheets, science writers' guide, background info, and multimedia are available online at http://www.nasa.gov/mission_pages/calipso/news/index.html.

For more information on Calipso, visit http://www.nasa.gov/calipso or contact Katie Lorentz at NASA Langley Research Center:
k.e.lorentz@larc.nasa.gov, 757-864-4052.

For more information on CloudSat, visit http://www.nasa.gov/cloudsat.