Scientists from NASA (National Aeronautics and Space Administration) have developed an instrument names ‘Soil Moisture Active Passive’ (SMAP) that can measure moisture in Earth’s soil with an unquestionable accuracy. According to reports, NASA is all set to launch the instrument on January 29, 2015; also, it will be NASA’s fifth Earth Science Mission in past 12 months.
The remote sensing SMAP basically is made up of three parts, a radar, a powerful radiometer and a rotating mesh antenna. The antenna in SMAP will be the largest rotating mesh antenna to be ever deployed in space.
The remote sensing device is called ‘Active‘ as it can emit its own signal and ‘Passive’ as it can record already existing signals. Instrument boasts dish that is 19.7 feet in diameter. The sensor installed in it will help scientists to record most accurate moisture is Earth’s soil.
Wendy Edelstein of NASA’s Jet Propulsion Laboratory, Pasadena, California, SMAP instrument manager said, “We call it the spinning lasso.” He said that the antenna is attached on one side to an arm with a crook in its elbow, which spins around the arm at about 14 revolutions per minute (one complete rotation every four seconds). He added, “The antenna caused us a lot of angst, no doubt about it.”
SMAP transmits microwave through radar that is reflected back from earth’s surface and radiometer installed in it detects the deviation in wave. After computational process scientists can get to know about moisture present in soil.
According to US space agency, variation in distribution of moisture in soil has several environmental effects including weather. However, with tiny and accurate measurements researchers can have close eye on distribution of moisture can use it for advantage of mankind.