ANSER Satellites

Constellation of 4 nanosatellites to monitor the quality of the water in reservoirs and swamps in Spain

The main goal of the ANSER project is to monitor the quality of the water in reservoirs and swamps in Spain, using technological advances to distinguish the different levels of contamination in its shallow layers. This set of nanosatellites will also allow the study of global warming caused by the increase of greenhouse gases in the atmosphere (especially the accumulation of carbon dioxide) and the effect that solar radiation has on our planet.

The four nanosatellites of the ANSER mission will fly in close formation (about 10 kilometres apart) and they are ready to work together, as a single satellite, with fragmented payloads on the different CubeSats. They will be managed by a distributed attitude control to avoid disorientation and the loss of any of them.

Alén Space’s Inter-satellite Link (ISL) system enables in orbit communications among satellites. This way, the ‘lead’ nanosatellite is the one in charge to connect with the ground station and to receive information from the other ‘follower’ nanosatellites, which allows the cluster to act as a single satellite. The ISL, which will operate in a 401-402 MHz radio frequency, can be optimised if its power and bitrate is modulated, thus allowing a greater transmission range among satellites, which in this mission could reach 100 kilometres.

Main instruments:

• The Cinclus instrument is part of this mission and allows remote sensing of continetal waters. Cinclus is a CDD photometer,consisting of 5 narrow spectral bands, located in the region of red and near infrared, with high sensitivity and radiometric resolution. Installed on a heliosynochronous polar orbit satellite, it will generate images of at least 50 km of swath and a spatial resolution of around 50 m, with coverages less than 30 days in the Iberian Peninsula.
• Cassegrain telescope with two mirrors with central dark in the primary. It makes use of freeform optics to reduce their size and reduce central darkion.

“As soon as our launch and early operations phase was complete, we began work to reconfigure Follower 1 to assume the Leader’s role in the cluster. This was achieved without any apparent decrease in its observation capabilities. However the Leader’s cloud detection functionality cannot be replicated by a Follower satellite. Instead we make use of Copernicus Sentinel satellite images to validate our hyperspectral data instead. This can’t be done in real time, but it still works. With this new configuration, ANSER’s mission is still 100% operational.”

• ISL - Alen Space