The success and reliability of the Argentine SAC platform SAC, designed and built by INVAP for the Argentine Space Agency (CONAE) has led to the decision of NASA to embark on the next satellite of the series, called SAC-D, a very complex instrument called Aquarius. The value of the NASA contribution to the SAC-D mission is about 200 million USD, and includes the Aquarius instrument and the cost of launching with a Delta II vehicle.
The scientific purpose of the SAC-D/Aquarius mission is to observe the Earth in order to obtain new information on climate change, by measuring the surface salinity of the oceans at a global scale. SAC-D will also be able to identify “hot spots” on the ground, to collaborate in the elaboration of fire risk cartography and to measure soil humidity, to prevent and early detect floods and other natural catastrophes.
This is the first satellite specifically design to provide monthly measurements at a global scale of variations in the sea water salinity, a key information to study the relationships between ocean currents and the water cycle, which, in turn, affects the ocean capacity to store and transport heat and regulate the Earth’s climate. The SAC-D/Aquarius Mission seeks to determine how the ocean responds to the combined effects of evaporation, precipitation, ice melt and river runoff on seasonal and inter-annual time scales, and their impact on the global distribution and availability of fresh water.
Sea surface salinity, along with sea surface temperature, determines the sea surface density. Recent technological advances have provided the ability to examine these processes using remote sensing tools via satellite, and will further understanding of how climate variations induce changes in the global ocean circulation and how our oceans respond to climate change and the water cycle.
Besides, the SAC-D will carry other instruments provided by INVAP, the Space Agencies of Italy, France and Argentina used to monitor global environmental changes, atmosphere parameters, natural risks and sea ice, to study the effects of cosmic radiation on electronic devices and to characterize space debris.
Among SAC-D payloads, the following may be mentioned:
• Microwave Radiometer. Provided by CONAE (MWR).
• New Infra-Red Sensor Technology (NIRST). Provided by CONAE.
• High Sensitivity Camera (HSC). Provided by INVAP.
• Data Collection System (DCS). Provided by CONAE.
• Technological Demonstration Package (TDP). Provided by CONAE.
• Radio Occultation Sounder for Atmosphere (ROSA). Provided by the Italian Space Agency (ASI).
• CARMEN-1. Provided by the Centre National d'Etudes Spatiales (CARMEN-1). French Spaces Agency (CNES), to study the effects of radiation on electronic components and the damage caused by space debris.
