Over the years, unmanned satellites of every description and purpose, including international satellites, were placed in orbit from Vandenberg by a widening variety of boosters.

Less than a century had gone by between the first unmanned satellite and interstellar travel via the LMT.

Just as the conquest of the moon began with unmanned satellites, Venus is now being investigated with unmanned sondes.

Manned reconnaissance stations were found to be a bad idea, since unmanned satellites could do the job much more cost-effectively.

The basic Vostok design has remained in use for some forty years, gradually adapted for a range of other unmanned satellites.

Almost all the station's scientific goals would be better achieved by unmanned satellites.

The laboratory, which is run by the National Aeronautics and Space Administration, tracks unmanned American satellites in space.

However, the Center focused primarily on designing unmanned satellites and spacecraft for scientific research missions.

The introduction of such systems would substantially alter the way space has been used since the first unmanned Soviet satellite went into orbit in 1957.

Earlier unmanned satellites had carried such sensors, he said, but they tended to be cumbersome and could have been difficult to mesh with the space shuttle's aerodynamic design.