Space · Mean-diameter reference · idealized sphere
Mars diameter and size comparison
Mars uses a mean diameter of 6,779 kilometers. That is a little over half of Earth’s mean diameter, a size comparison independent of where either planet is in its orbit.
6779000 m
Sourced measurement- Measurement
- Mean diameter · twice JPL mean radius
- Subject or version
- Mean-diameter reference · idealized sphere
- In kilometers
- 6,779 km (1 km = 1,000 m)
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A little more perspective
JPL’s mean radius is 3,389.50 kilometers; its equatorial radius is larger at 3,396.19 kilometers. The globe view does not resolve Olympus Mons or establish any Martian mountain’s elevation datum.
The displayed diameter is 2 × 3,389.5 km = 6,779 km. Doubling the source radius uncertainty gives ±0.4 km for diameter. The source defines mean radius through an equivalent-volume sphere. Its review date is not a new measurement date.
Quick facts
Mars uses a mean diameter of 6,779 kilometers. That is a little over half of Earth’s mean diameter, a size comparison independent of where either planet is in its orbit.
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Sources and measurement notes
Source review recorded . Maintained by Ishan Karunaratne. Suggest a correction with a source and the exact measurement being compared.