ASTRONOMY:
Laser Telemetry from Space
Joss Bland-Hawthorn, Alex Harwit, Martin Harwit*
Space missions currently on the drawing boards are expected to gather data at rates exceeding the transmission capabilities of today's telemetry systems by many orders of magnitude. Even on current missions, onboard data compression techniques are being implemented to compensate for lack of transmission speed. But while data compression can minimize the loss of data, it is no substitute for transmitting all of the data through a faster communications link. The transmission problem will soon reach crisis proportions and will affect astronomical, Earth resources, geophysical, meteorological, planetary and other space science missions. To overcome this communications bottleneck, the authors advocate the implementation of telemetry systems based on near-infrared laser transmission techniques. The fiber-optics communications industry has developed most of the basic components required for signal transmission in this wavelength band, which should make such a system affordable on scales relevant to the cost of anticipated space science missions.
J. Bland-Hawthorn is at the Anglo-Australian Observatory, Epping, NSW, 2121 Australia. A. Harwit is at Transparent Networks, Milpitas, CA 95035, USA. M. Harwit is at 511 H Street, SW, Washington, DC 20024, USA, and is Professor Emeritus, Cornell University, Ithaca, NY, USA.
*To whom correspondence should be addressed. E-mail: harwit{at}verizon.net
