spacecraft event time
Noun The coordinated universal time (UTC) as measured and recorded by the clock systems on board a spacecraft. It is the official time standard for timestamping events and data originating from the spacecraft itself. It is calculated as the sum of the Transmission Received Time (TRM) on Earth and the One-Way Light Time (OWLT), which is the time it takes for a signal to travel from the spacecraft to Earth.
This term is used exclusively in the context of space mission operations, data analysis, and telemetry. It provides a common temporal reference point for events occurring on a distant spacecraft, correcting for the signal delay between the spacecraft and Earth-based control stations.
- The anomaly was logged in the system at a spacecraft event time of 12:47:22 UTC.
- Engineers synchronized the instrument's data packets using the spacecraft event time.
- To determine when the image was actually taken, you must convert from Earth Received Time to spacecraft event time.
- SCET is the standard acronym for spacecraft event time and is frequently used in technical documentation and communications between mission specialists.
- The calculation SCET = TRM + OWLT is fundamental for retroactively establishing the precise moment an event occurred on the spacecraft.
- Earth Received Time (ERT): The UTC at which a signal from the spacecraft is received at a ground station on Earth.
- One-Way Light Time (OWLT): The elapsed time for a signal to travel from the spacecraft to Earth (or vice versa) at the speed of light.
- Ephemeris Time: A time standard used in orbital mechanics, often related to but distinct from the spacecraft's internal event time.
- Spacecraft UTC
- Onboard Time (less precise, as it may not specify the UTC correlation)
This is a highly technical, compound noun specific to aerospace engineering and planetary science. It is not used in everyday language. The term precisely denotes a calculated time standard, not the raw reading from an onboard clock, ensuring all mission data can be aligned to a common timeline.
- the coordinated universal time on board the spacecraft
- SCET = TRM + OWLT