A NASA spacecraft designed to monitor Earth’s soil moisture has arrived at Vandenberg Air Force Base, where crews will prep the satellite for a January launch.

The Soil Moisture Active Passive (SMAP) spacecraft arrived Wednesday after a short road trip from NASA’s Jet Propulsion Laboratory in Pasadena. 

In the next couple of months, the satellite will undergo final tests before being placed on top of a United Launch Alliance Delta 2 rocket in preparation for a planned Jan. 29 blastoff from Space Launch Complex-2.

This mission’s departure once was planned for early November, but was delayed nearly three months to allow for more testing for a critical component on the spacecraft.

SMAP will provide the most accurate, highest-resolution global measurements of soil moisture ever obtained from space, and will detect whether the ground is frozen or thawed, according to NASA.

The data will be used to boost scientists’ understanding of the processes that connect Earth’s water, energy and carbon cycles.

Scientists hope to use the satellite’s high-resolution global maps of soil moisture to understand how regional water availability is changing, with the information to be used to inform water resource management decisions.

“Water is vital for all life on Earth, and the water present in soil is a small but critically important part of Earth’s water cycle,” said Kent Kellogg, SMAP project manager at JPL. “The delivery of NASA’s SMAP spacecraft to Vandenberg Air Force Base marks a final step to bring these unique and valuable measurements to the global science community.”

Soil moisture is critical for plant growth and supplies aquifers, or the underground water supplies contained in layers of rock, sand or dirt.

Through evaporation, water in the soil cools the land surface and lower atmosphere while seeding the upper atmosphere with moisture that forms clouds and rain. 

Among the users of SMAP data will be hydrologists, weather forecasters, climate scientists, and agricultural and water resource managers. Additional users include fire hazard and flood disaster managers, disease control and prevention managers, emergency planners and policy makers.

To make its high-resolution, high-accuracy measurements, SMAP will combine data from two microwave instruments — a synthetic aperture radar and a radiometer.

From their place in space 426 miles above the planet, the instruments will be able to peer through clouds and moderate vegetation cover day and night to measure water in the top 2 inches of the soil.

SMAP is designed to operate for at least three years, and is expected to produce a global map of soil moisture every two to three days.

Noozhawk North County editor Janene Scully can be reached at jscully@noozhawk.com. Follow Noozhawk on Twitter: @noozhawk, @NoozhawkNews and @NoozhawkBiz. Connect with Noozhawk on Facebook.