Question

NASA’s Tracking and Data Relay Satellite (TDRS) System constellation resides at geosynchronous orbit (35,000km) altitude. If a technician at the Goddard Spaceflight Center in Maryland initiates a transmission to the Johnson Spaceflight Center in Houston over TDRS, how long will it be until JSC detects the transmission (one-way latency)? You may assume there is negligible processing delay on the satellite, and that c = 3x108 m/sec.

Answer 1

35,000 km = 35,000,000 m = 3.5 E107 m

t = S / v = 3.5 * 10E7 / 3.0 E10E8 = .117 sec