The Sun
An ordinary star, and the centre of everything here. Drawn to the same scale as the planets, only the edge of it fits on the page.
- Diameter
- About 1.39 million km, 109 Earths
- Holds
- About 99.8% of the Solar System's mass
- Light reaches Earth in
- About 8 minutes 20 seconds
Asteroid belt
Millions of rocky fragments circling between Mars and Jupiter - far more spread out than any picture shows. Its largest member is the dwarf planet Ceres.
- Lies
- About 2.2–3.2 AU from the Sun
- Largest member
- Ceres, about 940 km across
- Total mass
- A few per cent of the Moon's
Saturn's rings
Countless pieces of ice and rock, from grains of dust to boulders the size of a house, each orbiting Saturn on its own. Broad, and astonishingly thin.
- Made of
- Ice, with some rock
- Main rings span
- About 270,000 km
- Thickness
- Often only tens of metres
Mercury
The smallest planet and the closest to the Sun. With almost no air to hold heat, its days are scorching and its nights far below freezing.
- Diameter
- 4,879 km
- From the Sun
- 0.39 AU (58 million km)
- Year
- 88 Earth days
- Sunrise to sunrise
- 176 Earth days
- Moons
- None
Venus
Nearly Earth's size, wrapped in thick cloud of carbon dioxide that traps heat. It is the hottest planet, and it spins backwards.
- Diameter
- 12,104 km
- From the Sun
- 0.72 AU (108 million km)
- Year
- 225 Earth days
- Surface
- About 465 °C
- Moons
- None
Earth
The only world known to have life and liquid water on its surface. Its distance from the Sun defines the astronomical unit, AU.
- Diameter
- 12,742 km
- From the Sun
- 1 AU (150 million km)
- Year
- 365.25 days
- Day
- 24 hours
- Moons
- One
Mars
A cold desert world, red from iron oxide - rust - in its dust. It has the tallest volcano in the Solar System, Olympus Mons.
- Diameter
- 6,779 km
- From the Sun
- 1.52 AU (228 million km)
- Year
- 687 Earth days
- Day
- About 24 h 40 min
- Moons
- Two: Phobos and Deimos
Jupiter
The largest planet, more than twice the mass of all the others together. Its Great Red Spot is a storm wider than Earth.
- Diameter
- 139,820 km
- From the Sun
- 5.2 AU (778 million km)
- Year
- 11.9 Earth years
- Day
- About 9 h 56 min
- Made of
- Mostly hydrogen and helium
Saturn
A gas giant so light for its size that it is less dense than water. Its rings are the brightest and broadest in the Solar System.
- Diameter
- 116,460 km
- From the Sun
- 9.5 AU (1.43 billion km)
- Year
- 29.4 Earth years
- Day
- About 10 h 34 min
- Made of
- Mostly hydrogen and helium
Uranus
An ice giant tipped on its side, so each pole has decades of sunlight followed by decades of dark.
- Diameter
- 50,724 km
- From the Sun
- 19.2 AU (2.87 billion km)
- Year
- 84 Earth years
- Day
- About 17 h 14 min
- Tilt
- About 98°
Neptune
The farthest planet: a cold, dark ice giant with the fastest winds measured anywhere in the Solar System.
- Diameter
- 49,244 km
- From the Sun
- 30.1 AU (4.5 billion km)
- Year
- 165 Earth years
- Day
- About 16 h 6 min
- Winds
- Up to about 2,000 km/h