The Solar System at a glance: eight planets, measured
Published history
Every published version keeps its original contributor and change message.
Current version
Correct Venus day-vs-year fact (rotation, not solar day), declare solar-day convention, round volumes to 2 decimals
Contributor ly-gSAvJ · 2026-11-03
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The Solar System at a glance: eight planets, measured
Eight planets, one spreadsheet. Mean radii, day and year lengths, and moon counts - with live formulas computing how many Earths fit inside each planet.
Values are from NASA's Planetary Fact Sheet (mean radius, orbital periods). Moon counts are the confirmed tallies as of 2024; they keep climbing as surveys find more, so treat that column as a snapshot.
A note on conventions: "day length" here means a solar day - one sunrise to the next. For the gas giants a solar day is effectively their rotation period, but for Mercury and Venus the two differ wildly, which is exactly what makes those rows interesting.
Planets
Planet Radius (km) Volume (Earth = 1) Moons (2024) Distance from Sun (AU) Year (Earth days) Solar day (hours) Mercury 2440 0.06 0 0.39 88 4222.6 Venus 6052 0.86 0 0.72 224.7 2802 Earth 6371 1 1 1 365.3 24 Mars 3390 0.15 2 1.52 687 24.7 Jupiter 69911 1321.34 95 5.2 4333 9.9 Saturn 58232 763.59 146 9.58 10759 10.7 Uranus 25362 63.09 28 19.2 30687 17.2 Neptune 24622 57.72 16 30.1 60190 16.1 Things worth noticing
- Jupiter's volume works out to about 1,321 Earths. Every other planet combined fits inside it with room to spare.
- Venus spins backwards and so slowly that one full rotation takes 243 Earth days - longer than its 224.7-day year. Yet its solar day, shown in the table, is only about 117 Earth days: the backwards spin makes the Sun cross the sky faster than the planet turns.
- Saturn's moon count overtook Jupiter's in 2023 when 62 new moons were confirmed in one announcement.
- Mercury's solar day is the extreme case: it rotates exactly three times for every two orbits, stretching one sunrise-to-sunrise cycle to 176 Earth days - twice its own year.
Formulas at work
The Volume column is a live formula:
=ROUND((B2/$B$4)^3,2)cubes the ratio of each planet's mean radius to Earth's, rounded to two decimals. Change a radius and every volume recalculates. That's the point of a living document - correct the numbers as measurements improve and the comparisons take care of themselves.Sources: NASA Planetary Fact Sheet (nssdc.gsfc.nasa.gov/planetary/factsheet), IAU moon designations. License: CC-BY-4.0 - reuse freely with credit.
Fix sheet terminator: @endsheet on its own line
Contributor ly-gSAvJ · 2026-11-03
Read exact source · Restore by submitting this source as a new revision.
Read this version
The Solar System at a glance: eight planets, measured
Eight planets, one spreadsheet. Mean radii, day and year lengths, and moon counts - with live formulas computing how many Earths fit inside each planet.
Values are from NASA's Planetary Fact Sheet (mean radius, sidereal/orbital periods). Moon counts are the confirmed tallies as of 2024; they keep climbing as surveys find more, so treat that column as a snapshot.
Planets
Planet Radius (km) Volume (Earth = 1) Moons (2024) Distance from Sun (AU) Year (Earth days) Day length (hours) Mercury 2440 0.056175463413249714 0 0.39 88 4222.6 Venus 6052 0.8571837765788739 0 0.72 224.7 2802 Earth 6371 1 1 1 365.3 24 Mars 3390 0.15065247793867312 2 1.52 687 24.7 Jupiter 69911 1321.3373996052214 95 5.2 4333 9.9 Saturn 58232 763.5936424404122 146 9.58 10759 10.7 Uranus 25362 63.085228346372006 28 19.2 30687 17.2 Neptune 24622 57.7227702436509 16 30.1 60190 16.1 Things worth noticing
- Jupiter's volume works out to about 1,321 Earths. Every other planet combined fits inside it with room to spare.
- Venus rotates backwards and so slowly that its day (measured by the Sun) outlasts its year.
- Saturn's moon count overtook Jupiter's in 2023 when 62 new moons were confirmed in one announcement.
- Mercury's "day" column is its solar day: because it rotates three times for every two orbits, one sunrise-to-sunrise cycle lasts 176 Earth days, twice its year.
Formulas at work
The Volume column is a live formula:
=(B2/$B$4)^3cubes the ratio of each planet's mean radius to Earth's. Change a radius and every volume recalculates. That's the point of a living document - correct the numbers as measurements improve and the comparisons take care of themselves.Sources: NASA Planetary Fact Sheet (nssdc.gsfc.nasa.gov/planetary/factsheet), IAU moon designations. License: CC-BY-4.0 - reuse freely with credit.
Initial publication
Contributor ly-gSAvJ · 2026-11-03
Read exact source · Restore by submitting this source as a new revision.
Read this version
The Solar System at a glance: eight planets, measured
Eight planets, one spreadsheet. Mean radii, day and year lengths, and moon counts - with live formulas computing how many Earths fit inside each planet and how far each one sits from the Sun relative to us.
Values are from NASA's Planetary Fact Sheet (mean radius, sidereal/orbital periods). Moon counts are the confirmed tallies as of 2024; they keep climbing as surveys find more, so treat that column as a snapshot.
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