Utahn awaits CloudSat liftoff

Jay Mace was disappointed Friday when the launch of the revolutionary weather satellite , CloudSat, was scrubbed just 48 seconds before the scheduled liftoff. But after working on the project 10 years, he has no problem waiting a few more days.

In fact, launch of the Delta II rocket carrying CloudSat and its sister satellite CALIPSO was rescheduled for Sunday morning. But then, a refueling plane needed by the tracking aircraft wasn't available so the launch was put off again. The next possible date is Tuesday, said Mace, interviewed by telephone on Sunday.

An associate professor of meteorology at the University of Utah, Mace was at Vandenberg Air Force Base, Calif., for the launch attempt, then came back to Utah. He is a member of the science team for CloudSat, which will use radar to look straight down into clouds, discovering information about their interiors.

According to NASA, CloudSat's radar is "more than 1,000 times more sensitive than typical weather radar." Mace says data it will produce should indicate the amount of condensed water in the clouds and "how large the particles are.

"And ultimately we'll try to compare that information to predictions by global climate models," he added. Better understanding the effect that clouds have on global warming is expected to be one of the project's payoffs.

"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," says a NASA Web page. "CALIPSO and CloudSat will fly in formation with three other satellites . . . to enable an even greater understanding of our climate system."

CALIPSO stands for Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations; the $207 million CloudSat project carries a more obvious name.

Mace said Friday's delay was caused by a communications problem on ground, not with the satellite. "Everything is in good shape," he said of the satellite, and he believes it will launch this week.

While he's not on the CALIPSO science team, "we collaborate very closely" because the satellites will be working together.

CloudSat will orbit at 438 miles altitude, taking 99 minutes to circle the globe. The Earth's rotation will bring the satellite back to the same track every 16 days.

The satellite's primary benefit will be a better understanding of climate, he added.