Nebula Public Library

The increase of space debris means that active space debris removal is becoming more relevant. An active debris removal mission would have a positive effect (or risk reduction) for all satellites in the same orbital band. This leads to a dilemma: each space agency has an incentive to delay its actions and wait for others to respond. We model this scenario as a non-cooperative game between self-interested agents in which the agents are space agencies.

The main scope of this activity was to foster the exchange of expertise between the European Lidar Network (EARLINET) and Latin America Lidar Network (LALINET), and demonstrate the capability of joint research, setting the groundwork for GALION (The Global Atmosphere Watch Aerosol Lidar Observation Network) and future calibration/validation of ESA’s atmospheric satellite missions such as Aeolus and EarthCARE.

The development of High Altitude Pseudo-Satellites (HAPS) has reached an outstanding level of maturity, with several flight demonstrations that augur soon to have operational capabilities. ESA, aware of the synergies among satellite and HAPS services, set up the HAPPIEST study to analyse the impact of the erruption of aerostatic HAPS into the telecommunications market, currently covered by space and terrestrial networks. Furthermore, some complementary payloads can serve interesting applications such as Earth observation and navigation services.

The purpose of this study was to define the a communication subsystem architecture (including both ground and space segments, as well as operational methods) that allows robust RF TT&C links during superior solar conjunction phases. The defined architecture shall ensure robust and reliable links in scintillation regimes (i.e. at low SEP angles) where TT&C links are nowadays degraded, leading to occasional link interruptions. Similarly, the defined architecture shall ensure that at even higher scintillation regimes (i.e.