20 miles
32.19 kmLength · definition
The quantity is exact as entered. Comparisons use the clearly stated specimen, model or nominal measurement.
Length & distance
Just how long is 20 miles?
Our planet
20 mi
20 miles
The quantity is exact as entered.
32.19 kmLength
0 - shared origin
Phobos
Phobos is the larger and innermost moon of Mars, notable for its irregular shape and heavily cratered surface.
22.53 kmRepresentative mean diameter
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
20 miles is about 1.43 times the mean diameter of Phobos.
Measurements, assumptions & sources +
20 miles
Length: 32.19 km; definition.
The quantity is exact as entered. Comparisons use the clearly stated specimen, model or nominal measurement.
Phobos
Representative mean diameter: 22.53 km; approximate; range 18 km–27 km.
Mars’s larger moon is irregular, about 27 × 22 × 18 km. The 22.533 km comparison diameter is representative rather than a spherical edge.
The marked representative mean diameter is calibrated. Unmeasured illustration details are representative.
Measurement details
Why these numbers?
Compare 20 miles with the mean diameter of Phobos. The notes below explain how each value was chosen.
Phobos
22.53 kmRepresentative mean diameter · approximate · range 18 km–27 km
Mars’s larger moon is irregular, about 27 × 22 × 18 km. The 22.533 km comparison diameter is representative rather than a spherical edge.
- Comparing
- Length ↔ Representative mean diameter
- Relative size
- 20 miles is about 1.43 times the mean diameter of Phobos. 20 miles is approximately 42.8% greater than the mean diameter of Phobos.
How to read the visual
The diagram uses the recorded measurements. Details outside the marked spans do not set the scale.
- We use 22.53 km for the mean diameter of Phobos; the recorded range is 18 km–27 km.
- The mean diameter of Phobos: This is an estimate; check the notes for its rounding and uncertainty.
This comparison follows the selected length only; other dimensions may differ.
32,187 mmetres
105,600 ftfeet
2.1516 × 10⁻⁷ AUastronomical units
3.4022 × 10⁻¹² lylight-years
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