Video: Preparing Delta 2 and SMAP for flight

Engineers have so far been unable to restart a balky radar aboard NASA’s Soil Moisture Active Passive environmental satellite launched in January, robbing scientists of the most detailed maps of how much water is locked up in the top layers of Earth’s land masses.

The SMAP observatory to map soil moisture distribution from 426 miles in space and its workhorse booster have been cleared for launch Thursday morning from California.

Making a scientific measurement of planet Earth on a global scale never before attempted by NASA is the objective of an environment satellite to be mounted atop its booster rocket Tuesday in California.