Two precursor missions were also launched (RAE1 and RAE-2) in the early 70’s. They discovered Earth’s ionosphere is also a very strong emittor or Radio Frequency Interference. Also man-made signals were detectable from space, causing RAE-2 to be launched into lunar orbit. It detected that behind the Moon (relative to Earth), the RFI was significantly reduced, to below the detection threshold of...

Situational awareness of Earth-orbiting particles is highly important for future human activities in space. For optical observations of debris, multiple observations must be combined in order to determine the orbit of the observed object. It is generally uncertain, however, whether two arbitrary tracks are of the same object, and solving this problem can be computationally intensive. In this pa...

In contrast with ground applications the GNSS constellations are not optimized for space applications. Moreover, the different types of mission, i.e. Low Earth Orbit (LEO), Medium Earth Orbit (MEO), Geosynchronous Earth Orbit (GEO), have all specific requirements. Our motivation is to define an «Ubiquitous GNSS receiver (UGNSS)», i.e. a single receiver able to cope with all types of mission. Th...

This paper describes an architectural concept for a Small Lunar Exploration and Delivery System to operate as a platform for emplacing payloads into lunar orbit and onto the lunar surface, while providing mobility for surface exploration, science, and infrastructure. The concept leverages emerging services that are capable of delivering payloads to Low Earth Orbit (LEO), while utilizing new and...

The long-term evolution of artificial debris in earth orbit has been analyzed, taking into account a detailed traffic model, explosions, collisions and the effects of air drag. Several scenarios, most of them implementing mitigation measures discussed at international level, have been simulated over a 200-year time span. Moreover, the sensitivity of the results to different collision model assu...