Skip to content

The planets in order

Space and time · level 2, lesson 4 of 6

A question to start

Eight planets go round the Sun. Which is closest, which is farthest, and where is Mars?

The idea

In order from the Sun, the eight planets are:

Planet Distance from the Sun
Mercury 58 million km
Venus 108 million km
Earth 150 million km
Mars 228 million km
Jupiter 779 million km
Saturn 1,432 million km
Uranus 2,867 million km
Neptune 4,515 million km

The first four are small and rocky. Mars is the fourth planet, the next one out after the Earth. The last four are giants, made mostly of gas and ice.

The planets are spread out more and more as you go out: the gap between Saturn and Uranus is nearly twice the whole distance from the Sun to Jupiter.

rocky planetsJupiterSaturnUranusNeptune

The distances are to scale; the planets are drawn far too big.

Worked examples

1. Mars and Earth. \(228 - 150 = 78\) million km: the gap between their paths round the Sun.

2. Half as far again. \(228 \div 150 \approx 1.5\). Mars is about one and a half times as far from the Sun as the Earth.

3. The farthest. Neptune is \(4{,}515 \div 150 \approx 30\) times as far from the Sun as the Earth.

Try it

  1. Which planet is closest to the Sun?
  2. Which number is Mars, counting out from the Sun?
  3. Which planets are next to Mars?
  4. Which are the four giant planets?
Answers
  1. Mercury.
  2. Fourth.
  3. Earth and Jupiter.
  4. Jupiter, Saturn, Uranus and Neptune.

Common mistake

"The planets are evenly spaced." The rocky planets are bunched close to the Sun; the giants are spread far apart.

Where it leads