The mobile service tower rolls toward the United Launch Alliance Delta II rocket at Space Launch Complex 2 on Vandenberg Air Force Base in California. Aboard the rocket is NOAA's Soil Moisture Active Passive satellite, or SMAP, designed to produce the highest-resolution maps of soil moisture ever obtained from space. Launch was postponed today due to violation of upper-level wind shear constraints. Launch now is targeted for Jan. 31. To learn more about SMAP, visit http://www.nasa.gov/smap. Photo credit: NASA/Randy Beaudoin