|
NASA Langley Research Center (LaRC) is sponsoring the development of a revolutionary new concept for remote sensing from space. This concept is based on new technology and differs radically from previous paradigms, which call for building instruments that bolt to spacecraft. Langley's concept is called a 'sensorcraft.' The term sensorcraft simply designates a spaceflight remote sensing system that does not distinguish between the instrument, which performs a remote measurement, and the spacecraft bus, which provides the operational resources needed by the instrument in orbit. It integrates the resource requirements of both to minimize size, power consumption and cost. The gas and aerosol monitoring sensorcraft (GAMS) is a technology development project that seeks to revolutionize the remote sensing technique of solar occultation. An inherent limitation of solar occultation is the spatial and temporal coverage from a single spacecraft. For any given orbit there are at most two opportunities to take data, one at sunrise and one at sunset. A single satellite takes months to obtain a sufficient number of events to achieve global coverage. One solution to quicker global coverage is to launch several copies of the satellite. Unfortunately, by today's standards, this is very costly in hardware, launch costs, and in mission operations. This paper describes the effort to produce a small, inexpensive satellite that requires minimal ground support effort. Such a satellite would be cost effective to mass-produce, be a good 'payload of opportunity,' and allow for a constellation approach yielding global coverage in a matter of days. The GAMS project will produce an autonomous sensorcraft with mass of 60 kg, requiring less than 50 W average power and costing less than $2 M. GAMS will also perform extensive onboard processing which not only helps to reduce size and weight, but will minimize mission operations requirements. A validation flight is targeted for Shuttle deployment in late 1999. This paper discusses the mission concept and the key technologies GAMS will employ to achieve a tenfold decrease in science mission costs.
|
