In the context of the National Space Program of the Argentine National Space Activities Commission (CONAE, in Spanish) in cooperation with the Italian Space Agency (ASI, in Italian), INVAP S.E. (an Argentine state-owned applied research company) has been developing the SAOCOM 1 and 2, the earth observation satellites that will be part of the Italian-Argentine System of Satellites for the Benefit of the Society, for Emergency Management and Economic Development (SIASGE, in Spanish).
The aim of these satellites, which were specifically designed to prevent, monitor, mitigate and assess natural and anthropogenic disasters, is to measure soil moisture values to be used in emergencies, such as detection of hydrocarbon spills in the seas and the follow-up of water during floods.
The SIASGE mission includes two constellations of satellites —one of them comprises the Argentine SAOCOM satellites and the other the Italian COSMO SkyMed satellites— that will be put into a polar sun synchronous orbit (6.12 a.m LTAN) 619.6 km above the earth's surface. This orbit allows to provide global cartographic services of the earth and to keep the satellites' solar panels pointing to the Sun almost always. Thus, by combining the capabilities of both constellations, images of any disaster could be captured anywhere on the planet and be updated every 12 hours.
INVAP has been developing the SAOCOM 1 and SAOCOM 2 constellations, made up of two satellites each: SAOCOM 1A and 1B, and SAOCOM 2A and 2B. The first two satellites are in their integration and testing stage at INVAP’s headquarters in San Carlos de Bariloche, and are expected to be launched in 2017. Each satellite weighs 3 tonnes and is 4.5 meters high, with a diameter of 1.5 meters. The radar deployable antenna (Synthetic Aperture Radar or SAR) is 10 meters long and 3.5 meters wide. Both satellites have the same requirements concerning design, functionality and effectiveness, so that they are being developed, assembled and tested simultaneously in order to have two identical satellites that will be launched about one year apart.
This satellite series involves the development of active instruments that operate in the range of the microwaves. The main goals of the SAOCOM 1 mission correspond to the capabilities of the SAR instrument:
- To provide the information of the polarimetric SAR, which operates in the range of the L-band, regardless of meteorological conditions, the time of day, and the different areas of the earth; in real time and in storage mode, with a space resolution ranging between 10 and 100 meters and with different viewing angles.
- To meet the needs of the applications considered in the Space Information Cycles (CIE, in Spanish) and the Argentine National Space Program (PEN, in Spanish).
- To achieve the operational integration of the SIASGE (the Italian-Argentine System of Satellites for the Benefit of the Society, for Emergency Management and Economic Development).
- To develop specific products by using the SAR information, particularly soil moisture maps, which contribute to the agriculture, hydrology and health fields. Besides, taking advantage of the interferometry, information about ground displacements can be obtained, which is useful for a variety of applications.