Round-trip Light Time (Noun)
Meaning
The elapsed time it takes for a signal to travel from Earth to a spacecraft (or other body) and back to the starting point.
Classification
Nouns denoting time and temporal relations.
Examples
- As the spacecraft flew further away, the round-trip light time increased, making real-time communication between the spacecraft and mission control increasingly difficult.
- Scientists carefully considered the round-trip light time when designing the communication system for the Mars explorer, knowing that even a small delay could cause critical errors.
- During the Voyager mission, the round-trip light time between Earth and the spacecraft varied from 20 minutes to over 18 hours as it traversed the outer reaches of the solar system.
- Because of the significant round-trip light time, signals sent from Earth to the New Horizons spacecraft during its flyby of Pluto were delayed by over 4 hours, making real-time adjustments impossible.
- When planning the Europa Clipper mission, engineers had to factor in the round-trip light time of approximately 40-50 minutes, which would impact the timing of spacecraft maneuvers and scientific instrument operations.