Kilometric baseline space interferometry

摘要

Abstract: Two versions of a kilometric interferometer withequivalent science capabilities have been studied, onelocated on the Moon and the other operating as afree-flyer. It has been found that the Moon is not theideal site for interferometry because of tidal andmicro-meteorite induced disturbances, the need for longdelay lines and the large temperature swings from dayto night. Automatic deployment of the Moon- basedinterferometer would be difficult and site preparationand assistance by man appear to be essential. Thefree-flyer would be implemented as a very accuratelycontrolled cluster of independent satellites placed ina halo orbit around the 2nd Lagrange point of theSun-Earth system. Both versions could attain therequired scientific performances and each one needs thesame type of metrology control. The free-flyer isintrinsically advantageous because of itsreconfiguration flexibility, quasi-unlimited baselinelength and observation efficiency (the Moon-basedinterferometer cannot be operated during the lunar daybecause of stray light). The free-flyer is bettersuited for implementation in the near or mid-termfuture, but the Moon-based version could be consideredin the long term when a human presence would permitmaintenance and upgrading leading to a longer lifetimewith continuous performance enhancement.!18