PROTECTING THE MOON FARSIDE RADIOTELESCOPES FROM RFI PRODUCED AT THE FUTURE LAGRANGIAN-POINTS SPACE STATIONS

摘要

The coming space colonization will involve the possibility of establishing Space Stations (Gateways in the NASA jargon) at some Lagrangian Points in the vicinity of the Earth (5 points in the Earth-Moon system plus 2 more in the Sun-Earth system). Independently of this, the Moon Farside is the only place around the Earth that man-made radio frequency interferences (RFI) clearly cannot reach. In other words, a radio telescope or an array of antennas located in the centre of the Moon Farside would be able to achieve radio observations enormously clean and sensitive. In this paper we study the problems of radio wave diffraction that arise from the future RFI produced at the Lagrangian Points with particular regard to the frequency bands that are important in radioastronomical research. It is hoped that the future exploitation of the Moon Farside by several space-faring nations will take into account the "ecological" need to preserve at least the central part of the Moon Farside. In our understanding, this means the creation of an official RFI-Free Zone within a circle centered at crater Daedalus (i.e at around the antipode of the Earth) and extending 30 degrees in both latitude and longitude.