Aquarius Mission Launched to Measure Ocean Salinity

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A photo showing the author turning over a cover crop of winter rye on Jan. 2, 2012. In three of the past six years, ground freeze-up, which historically occurred by November, has been delayed into January.

Aquarius launches to orbit June 10, 2011
Aquarius launching to orbit June 10, 2011 (left) and during testing (right). Photo Sources:

On Friday, June 10th, 2011, the Aquarius/SAC-D observatory successfully launched aboard a Delta II rocket at 10:20:13 EST. Launched from NASA’s Space Launch Complex-2 at Vandenberg Air Force Base in California, Aquarius is the primary instrument on the SAC-D spacecraft. It consists of three passive microwave radiometers to detect the surface emission that is used to obtain salinity and an active scatterometer to measure the ocean waves that affect the precision of the salinity measurement. The Aquarius instrument was built by NASA’s JPL and Goddard’s Space Flight Center.


Aquarius Observatory during integration and test
Aquarius Observatory during integration and test. Photo source:

The purpose of this mission is to measure Earth’s salinity across the oceans in order to better predict climate change and variability, such as El Ni̱o. The mission will observe the water cycle and ocean circulation in order to monitor the exchange of freshwater between ocean, atmosphere, and sea ice that affects climate. Aquarius will stay in orbit for three years, repeating its global pattern every seven days in order to adequately record maps of the global salinity distribution. This project was conducted in collaboration with Argentina’s Comision Nacional de Actividades Espaciales, with contributions by Brazil, Canada, France, and Italy.