Two NASA
satellites designed to make unprecedented measurements of Earth's clouds and
atmosphere must wait yet another day to begin their mission after a high winds prevented
their launch early Tuesday.
The high upper level
winds were detected just four minutes before liftoff, forcing flight controllers to scrub the latest launch attempt for NASA's
CloudSat
and CALIPSO satellites and their Delta 2 booster. The two satellites were scheduled
to rocket spaceward from California's Vandenberg Air Force Base precisely at
6:02 a.m. EDT (1002 GMT).
"We are in
the process of preparing for a 24-hour recycle," NASA launch commentator Bruce
Buckingham said after the scrub, which occurred after what had been a nearly
flawless countdown before the high winds were detected.
Launch
controllers are now preparing to launch NASA's CloudSat and CALIPSO satellites
on April 26 at 6:02 a.m. EDT, Buckingham said. Because the space shot must
launch exactly on time, there is little room to accommodate last minute issues
such as high upper level winds, he added.
A similar
last-minute glitch - a communications problem with the CALIPSO spacecraft - scrubbed
an initial April 21 launch attempt just 48 seconds before liftoff. The unavailability
of a refueling plane for a radar tracking aircraft required to monitor the
launch also prevented Saturday and Sunday launch plans, NASA said.
CloudSat
and CALIPSO are designed to study clouds and aerosols - fine particles
suspended in Earth's atmosphere - in three dimensions.
The $185
million CloudSat mission will use a powerful, 90 gigahertz radar to penetrate
clouds and identify individual cloud particles, water and snow. The $223
million CALIPSO - or Cloud-Aerosol Lidar and Infrared Pathfinder Satellite
Observations - mission a cooperative effort between NASA and the French Space
Agency (CNES), and features a laser-ranging lidar instrument and two other
tools to study aerosol distribution in the Earth's atmosphere.
Once
launched, CloudSat and CALIPSO are expected to reach an orbit of 438 miles (705
kilometers) and join France's PARASOL
satellite and NASA's Aqua
and Aura
spacecraft to make up the "Afternoon Train" Earth-watching system, NASA said.