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round-trip light time

round-trip light time

9.6
The time it takes for a light signal to travel to a spacecraft or planet and back
  • noun
  • Specialized
translation icon : tiempo de ida y vuelta de la luz
  • Because of the round-trip light time, communication with the probe is delayed by several minutes.

Examples

  • The round-trip light time to Mars can be over 24 minutes depending on the planets' positions.

  • Scientists calculate the round-trip light time before sending commands to distant spacecraft.

  • The round-trip light time to Mars is approximately 22 minutes.

  • What is the round-trip light time to the nearest star?

  • The round-trip light time to Mars can vary significantly based on its distance from Earth.

  • Engineers must consider the round-trip light time when programming commands for remote space probes.

  • Understanding the round-trip light time is essential for effective communication with distant spacecraft.

Synonyms

RTLT
vsround-trip light time
  • Specialized
9.9

Time it takes for a signal to go from Earth to a spacecraft and back

is measured using the speed of light rather than unspecified timing

How Long

round-trip light time
  • Specialized
9.6
one-way light time
  • Specialized
9.6
light hour
  • Specialized
8.1
light minute
  • Specialized
1 8.1

Surface Forms

Morphology

round-trip + light + time

The phrase is directly built from 'round-trip' (a journey there and back) + 'light' (electromagnetic radiation / the speed of light) + 'time' (duration), so the meaning — the duration for light to travel to a target and back — is predictable from the parts. Although it's a technical term, the composition is transparent and similar constructions exist in other languages, so a B1 learner who knows the constituents can reasonably infer the meaning.

Etymology

Round-trip light time shows a simple picture: a light signal leaves Earth, reaches a spacecraft, and then comes back, so the light makes a round-trip and the time is how long that journey takes. That's why the phrase measures the 'delay' before Earth gets an answer from a distant spacecraft.