The statement suggested that the reactor at least be placed in a higher orbit so it would not affect experiments aboard other satellites.

Before 1982, he said, sensing instruments aboard satellites were unable to deal with the distorting effect on temperature measurements of moisture in the earth's atmosphere.

Sensors aboard such satellites can also spot nuclear blasts.

Thermometers on land, in the sea and aboard satellites show warming.

The slight daily influence of moonlight on atmospheric temperature was measured by instruments aboard satellites able to record the microwave emissions of atmospheric oxygen.

Introduced in August 1994 and was successful in the market being used aboard several orbiting satellites and microsatellites.

In addition to ground-based lightning detection, several instruments aboard satellites have been constructed to observe lightning distribution.

All of the technologies for the system have already been developed and need only to be adapted for use aboard satellites, Mr. Hillis said.

Ultraviolet and X-ray sensors aboard monitoring satellites went into overload.

Small versions of the system had been tested aboard satellites flung into sun-centered orbits.