1 light-second
299,800 kmLength · definition
The quantity is exact as entered. Comparisons use the clearly stated specimen, model or nominal measurement.
Length & distance
Just how long is 1 light-second?
Solar neighbourhood
1 light-s
1 light-second
The quantity is exact as entered.
299,800 kmLength
0 - shared origin
Earth–Moon distance
The Earth–Moon distance is the average space between the centres of the Earth and the Moon.
384,400 kmDistance
0 - shared origin
Both rulers start at the same zero and share one linear scale. Artwork keeps its original proportions. A ruler represents the selected distance or a measurement not visible in this view.
A little perspective
The Earth–Moon distance is about 1.28 times 1 light-second.
Measurements, assumptions & sources +
1 light-second
Length: 299,800 km; definition.
The quantity is exact as entered. Comparisons use the clearly stated specimen, model or nominal measurement.
Earth–Moon distance
Distance: 384,400 km; average.
Average centre-to-centre distance. The Moon’s orbit is not a circle.
NASA — Earth and Moon by the numbers
The marked distance is calibrated. Unmeasured illustration details are representative.
Measurement details
Why these numbers?
Compare 1 light-second with the Earth–Moon distance. The notes below explain how each value was chosen.
Earth–Moon distance
384,400 kmDistance · average
Average centre-to-centre distance. The Moon’s orbit is not a circle.
- Comparing
- Length ↔ Distance
- Relative size
- The Earth–Moon distance is about 1.28 times 1 light-second. The Earth–Moon distance is approximately 28.2% greater than 1 light-second.
How to read the visual
The diagram uses the recorded measurements. Details outside the marked spans do not set the scale.
- The Earth–Moon distance: This is an average value; individual or instantaneous measurements may vary.
This comparison follows the selected length only; other dimensions may differ.
299,790,000 mmetres
983,570,000 ftfeet
186,280 mimiles
0.002004 AUastronomical units
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