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RTLT

RTLT

9.9
Time it takes for a signal to go from Earth to a spacecraft and back
  • noun
  • Specialized
translation icon : tiempo de ida y vuelta de la luz
  • The RTLT to Mars can exceed forty minutes, which complicates real-time control of spacecraft.

Examples

  • Engineers calculated the RTLT before issuing remote commands to the lander.

  • The RTLT for the Mars rover is approximately 20 minutes.

  • Understanding the RTLT is critical for planning communications with distant probes.

  • NASA measures the RTLT to ensure accurate communication.

  • Engineers calculated the RTLT to ensure timely communication with the spacecraft.

  • The RTLT of the signal sent to the satellite was crucial for mission planning.

  • Understanding the RTLT helps scientists predict when they will receive data from Mars.

Synonyms

round-trip light time
vsRTLT
  • Specialized
9.6

The time it takes for a light signal to travel to a spacecraft or planet and back

is the travel time described without naming the measurement method

How Long

days
1.0
hours
  • Informal
42 1.0
RTLT
  • Specialized
9.9
second
  • Specialized
1.0
millisecond
26 2.5

Surface Forms

RTLT singular
RTLTs plural

Morphology

RTLT = R + T + L + T

RTLT is an initialism whose component letters do not transparently convey meaning; the meaning depends on knowing the expanded phrase (round-trip light time).

Etymology

The word RTLT stands for round-trip light time, made of round-trip, light, and time, and it means the 'time' a 'light' signal needs to go to a spacecraft and come back. Think of it like a light 'echo': that delay is why engineers must wait before commands from Earth reach distant spacecraft.