Patagonian satellites
In the Andean foothills of Bariloche, the high-technology company INVAP S.E. designs and builds complex systems, including nuclear reactors, radar systems, and advanced satellites. Founded in 1976 as a spin-off from Argentina's National Atomic Energy Commission, INVAP is a partner for the national space agency, CONAE (Comisión Nacional de Actividades Espaciales). This collaboration places Argentina in a select group of countries capable of developing sophisticated Earth observation and communications satellites from the ground up. INVAP was the first Latin American company certified by NASA to provide space technologies.
The company's space efforts are most visible in the satellites developed for CONAE's Scientific Applications Satellite (SAC) series. A landmark mission was SAC-D/Aquarius, a partnership with NASA launched on June 10, 2011. The SAC-D spacecraft, built by INVAP, carried nine instruments, with the primary one being NASA's Aquarius sensor. This instrument used three radiometers operating at a frequency of 1.4 GHz to measure sea surface salinity. It could detect variations in salt concentration with an accuracy of 0.2 practical salinity units (psu). For nearly four years, the mission mapped the entire ocean every seven days, generating the first global maps of ocean salinity and collecting more data in its first few months than had been gathered in the previous 125 years.
Radar eyes on the Earth
INVAP also developed the two satellites for Argentina's SAOCOM constellation (Satélite Argentino de Observación Con Microondas). SAOCOM 1A launched on October 8, 2018, followed by SAOCOM 1B on August 30, 2020. Each 3,050 kg satellite orbits at an altitude of 620 kilometers. Their primary instrument is a powerful L-band Synthetic Aperture Radar (SAR). This type of radar actively transmits microwave signals and measures the backscatter to create images of the Earth's surface, day or night, regardless of cloud cover.
The L-band frequency (around 1.275 GHz) is particularly effective for measuring soil moisture because the signal can penetrate vegetation and the top layer of soil. This capability helps agriculture by providing moisture maps for crop management and helps hydrology by improving flood and drought forecasting. The radar's large antenna, with a radiating area of 35 square meters, allows it to capture images with a resolution ranging from 7 to 100 meters.
The SAOCOM satellites operate jointly with the Italian Space Agency's four COSMO-SkyMed satellites, which use X-band radar. Together, they form the Italian-Argentine System of Satellites for Emergency Management (SIASGE), enabling rapid response to natural disasters with twice-daily coverage. Besides Earth observation, INVAP has also built geostationary communications satellites for the Argentine operator ARSAT, including ARSAT-1 and ARSAT-2, launched in 2014 and 2015 respectively.