The order of the planets
From the Sun outward: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune. Four small rocky worlds, then a gap full of asteroids, then four giants.
Updated on October 7, 2026
The eight planets in order
Distances are mean distances from the Sun — orbits are ellipses, so the real figure moves. The moon counts change as new ones are confirmed, and the date they were checked is shown below the table.
| Planet | Mean distance from the Sun (10⁶ km) | ua | Equatorial radius (km) | Mass (kg) | Orbital period (days) | Rotation period (h) | Moons | Mean temperature (°C) |
|---|---|---|---|---|---|---|---|---|
| 1. Mercury | 57.9 | 0.387 | 2,440 | 3.301 × 10²³ | 87.97 | 1,407.6 | 0 | 167 |
| 2. Venus | 108.2 | 0.723 | 6,052 | 4.8673 × 10²⁴ | 224.7 | 5,832.5 (retrograde) | 0 | 464 |
| 3. Earth | 149.6 | 1.000 | 6,378 | 5.9722 × 10²⁴ | 365.26 | 23.93 | 1 | 15 |
| 4. Mars | 228.0 | 1.524 | 3,396 | 6.4169 × 10²³ | 686.98 | 24.62 | 2 | -65 |
| 5. Jupiter | 778.5 | 5.204 | 71,492 | 1.8982 × 10²⁷ | 4,332.59 | 9.93 | 97 | -110 |
| 6. Saturn | 1,432.0 | 9.573 | 60,268 | 5.6834 × 10²⁶ | 10,759.22 | 10.66 | 274 | -140 |
| 7. Uranus | 2,867.0 | 19.165 | 25,559 | 8.681 × 10²⁵ | 30,685.4 | 17.24 (retrograde) | 28 | -195 |
| 8. Neptune | 4,515.0 | 30.178 | 24,764 | 1.0241 × 10²⁶ | 60,189 | 16.11 | 16 | -200 |
Moons — Data checked on October 7, 2026.
Source: NASA — Planetary Fact Sheet (NSSDCA) e NASA Science: Solar System
Why the order looks like this
The split into rocky inner planets and giant outer ones is not a coincidence. Close to the young Sun it was too hot for water, methane and ammonia to stay solid, so only metals and silicates could condense, and the planets that formed there ended up small. Beyond the frost line, roughly where the asteroid belt now sits, ice was available in quantity, cores grew much faster and the biggest of them captured huge envelopes of hydrogen and helium.
A note on mnemonics: the classic "My Very Educated Mother Just Served Us Nine Pizzas" ended in Pluto. Since the IAU resolution of 2006 there are eight planets, so the last word has to go — "Noodles" is the usual fix.
Source: NASA — Planetary Fact Sheet (NSSDCA) e NASA Science: Solar System
Order of size, which is a different list
By radius the order is Jupiter, Saturn, Uranus, Neptune, Earth, Venus, Mars, Mercury. Jupiter’s equatorial radius, 71,492 km, is more than 11 Earths across, and it holds about twice the mass of everything else in the Solar System put together, planets, moons and asteroids included.
Source: NASA — Planetary Fact Sheet (NSSDCA) e NASA Science: Solar System
How to read this page
How to read the numbers here
Every value on "The order of the planets" comes from the source named beside its section, never from an estimate of our own with no origin.
Where the data comes from
Each section of "The order of the planets" names its official source; the verification date sits at the top of the page.
Linked to the rest of the module
"The order of the planets" is one of this module’s reference pages; the glossary below defines the technical terms used here.
More about “The order of the planets”
Who carries the solar system’s mass
The eight planets add up to about 2.6676 × 10²⁷ kg, and Jupiter alone accounts for 71.2% of that. The two gas giants, Jupiter and Saturn, together hold 92.5% of all planetary mass.
The ratio between the largest and smallest radius on the "The order of the planets" list is about 29-fold — Jupiter next to Mercury at that scale is a beach ball next to a marble.
Words on this page
Astronomical unit
The solar system’s reference distance, fixed at exactly 149,597,870,700 metres since 2012, close to the average Earth–Sun distance. It saves writing every planet’s orbit in kilometres with ten digits.
Standard definition by IAU — International Astronomical Union · Astronomical unit
Exoplanet
A planet orbiting a star other than the Sun. Most were found indirectly, by the star’s faint dimming as the planet crosses in front of it (transit) or by the gravitational wobble it causes in the star (radial velocity), not by direct image.
Standard definition by NASA Exoplanet Archive · Exoplanet
Launch window
The span of time in which a rocket can lift off and still reach its planned orbit or destination. For a trip to another planet that window can last only a few weeks and only returns at the next favourable alignment, so missing it costs months or years of waiting.
Mole
The SI counting unit for atoms, molecules or other entities: one mole is exactly 6.02214076 × 10²³ of them, by the definition fixed in 2019. It is what ties a mass in grams to a number of particles.
Standard definition by BIPM — Bureau International des Poids et Mesures (SI) · Mole
Standard uncertainty
The margin attached to a measured value, usually written in parentheses on the last digits. A constant that is "exact by definition" has zero standard uncertainty; a measured one, like the gravitational constant G, always carries some.
Standard definition by BIPM — Bureau International des Poids et Mesures (SI) · Standard uncertainty