President Reagan’s order of a year ago that NASA develop apermanently manned U.
S. space station (SN: 2/4/84, p. 69) came onlyfour months after a National Academy of Sciences panel has reportedfinding “no scientific need” for such a station “duringthe next 20 years” (SN: 9/24/83, p. 199).
Some space researchershave feared that visible support might result in their field’sbeing saddled with a disproportionate share of the station’smultibillion-dollar cost, and proposals for scientific studies to beconducted from the facility have been relatively slow to emerge. Last week, however, NASA and the University of Arizona signed amemorandum of understanding to pursue what Eugene Levy, director of theuniversity’s Lunar and Planetary Laboratory in Tucsn, calls”the most exciting scientific project that one could think of doingfrom this space station.” Its goal: the detection and study of planetary systems around otherstars. The plan calls for the development of an extremely accurateastrometric telescrope, designed to detect the presence of planets itcannot actually see but which would make their presence known by theirgravitational effects on the motions of the stars they circle. Theinstrument, to be based on the design of one now in operation at theUniversity of Pittsburgh’s Allegheny Observatory, would be carriedup by the space shuttle and installed on the station to operate for aslong as 20 years. Above earth’s atmosphere, says Levy, it could becapable of detecting planet-caused stellar “wobbles” as smallas 0.00001 second of arc, and the long lifetime is needed because even amassive planet may have to circle its star completely to produce anobservable effect.
(Jupiter takes about 12 years to orbit the sun.)Such an instrument could be flown as an independent satellite, Levyadmits, but it would then be necessary to provide all of asatellite’s “housekeeping” functions, whereas the spacestation might already have them available. The station could also be afar easier way to deal with whatever servicing needs might show upduring two decades in space.
Furthermore, Levy says, locating individual planets is not reallythe point. “The real question of intellectual substance,” hesays, is to find out whether planetary systems are a “general,natural consequence” of star formation. The plan (if it gets funded) calls for the NASA Ames ReserachCenter at Moffett Field, Calif., to manage the design, construction anddeployment of the telescope, while the University of Arizona establishescontrol facilities on the ground and manages the observing program.