Heliocodex

The Sun, its worlds and everything beyond

Our corner of the universe, at its true size

Real photographs and real measurements, from the Sun out to the oldest light there is. Fly through it in 3D, learn how it works in short lessons, or step outside and find what is above you tonight.

Enter the 3D solar systemStart learning

The Sun as a glowing orange-red ball, mottled and streaked with dark filaments, with flame-like prominences at its edge.
  1. A grey globe covered in craters of every size, some with bright rays.Mercury
  2. A smooth cream-white globe with faint tan swirls of cloud.Venus
  3. The whole Earth, with Africa, the white ice of Antarctica and swirls of cloud over blue sea.Earth
  4. A rust-orange globe with dark markings, a white polar cap and a long canyon across its middle.Mars
  5. A globe banded in cream, orange and rust, with the round Great Red Spot below the middle.Jupiter
  6. A pale gold globe circled by wide, thin rings seen at a slant.Saturn
  7. A plain pale blue-green globe with almost no markings.Uranus
  8. A deep blue globe with a dark oval spot and thin white streaks of cloud.Neptune
The Sun and its eight planets in real spacecraft photographs, all drawn to one scale. The distances would never fit: at this size, Neptune would be about 5 kilometres off to the right. See it at true size and distance.
The 3D view seen from above at a slant: the paths of the planets round the Sun as fine rings, the planets as points of light on them, and the stars behind.

Explore in 3D

The whole Solar System, where it is today

Every planet and its main moons in their real places, worked out from NASA’s orbital data. Click a world to glide to it, zoom out past the stars to the Milky Way and the cosmic web, or switch on easier to see to make the planets large enough to spot. Works on a phone.

Enter the 3D solar system

How far out they are

The same worlds at their real distances from the Sun. Each mark is twice as far out as the one before; on an even scale, the four rocky planets would be squeezed into the first twentieth.

  1. Mercury0.39 au3 light minutesSmall, fast and cooked on one side.
  2. Venus0.72 au6 light minutesEarth's twin in size, and a furnace in every other way.
  3. Earth1.00 au8 light minutesThe only place we know of with life.
  4. Mars1.52 au13 light minutesA cold desert that used to have water.
  5. Jupiter5.2 au43 light minutesMore massive than all the other planets put together.
  6. Saturn9.5 au1 h 19 min of lightThe ringed planet, light enough to float on water.
  7. Uranus19.2 au2 h 40 min of lightThe planet that rolls on its side.
  8. Neptune30.1 au4 h 10 min of lightThe farthest planet, found by maths before sight.

Beyond the eight planets: 62 moons, dwarf planets, asteroids and comets are set out on the map of worlds. Their pages are outlines for now, and are being written.

Learn

From the ground under your feet to the oldest light

101 short lessons, each written at more than one depth, set out by how long their light takes to reach you. Begin with ten first looks that cover the whole subject, or go straight to the part you want. 31 more are outlined and being written.

Begin with ten lessons All 101 lessons

  1. Finding your way
  2. Moons
  3. The Sun
  4. Planets
  5. Asteroids, comets and the far edge
  6. Stars
  7. Planets round other stars
  8. White dwarfs, neutron stars and black holes
  9. The Milky Way
  10. Galaxies
  11. The universe

Look up

What is above you tonight

A live map of your own sky, for wherever you are and whenever you look, with every planet and bright star named.

Open tonight’s sky

  • Meet a starAll 8,770 stars you can see by eye, and the one whose light set out when you were born.
  • The atlasFlat charts of everything in the 3D view, drawn to scale and good enough to print.
  • GlossaryEvery word on the site, explained in a line.