American orbital launch vehicle family with Thor first stage and a delta second stage.
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Syncom 2 was the first geosynchronous satellite. Although the period was 24 hours and the spacecraft remained at a nearly constant longitude, the orbit was inclined at 33 degrees so it was not truly geostationary but moved in an elongated figure eight pattern 33 degrees north and south of the equator.
Geosynchronous OrbitExplorer 17 carried four pressure gauges for the measurement of total neutral particle density, two mass spectrometers for the measurement of certain neutral particle concentrations, and two electrostatic probes for ion concentration and electron temperature measurements.
Low Earth Orbit