The proposal, led by Joseph Lazio, of the Naval Research Laboratory in Washington, DC, is to create an array of three arms arranged in a Y-shape, each of which would be 500 metres long and contain 16 antennae. Each arm would be made of a plastic film that could be rolled out onto the surface of the moon, either by robots or by astronauts.
A second project, headed by Michael Collier, of the NASA Goddard Space Flight Centre, would examine how the solar winda stream of charged particles ejected from the suninteracts with the tenuous lunar atmosphere close to the moons surface. Such bombardment produces low-energy X-rays that would be detected on the surface of the moon.
The third and fourth projects are similar both to each other and to earlier ventures dropped on the moon by the Apollo and the Soviet Luna missions in the late 1960s and 1970s. Some 35 years on, reflectors placed on the lunar surface are still used by scientists interested in geophysics and geodesy . Most of the reflectors are clustered close to the lunar equator. The proposals, led by Stephen Merkowitz, also of NASAs Goddard Space Flight Centre, and Douglas Currie, of the University of Maryland, are to sprinkle some more sophisticated versions over more of the moons surface.
Such efforts may attract little attention compared with the launch of the space shuttle Endeavour this week. Nevertheless, when NASA argues that putting people into space inspires young people to study science, it is precisely these endeavours that it wishes to encourage.
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