The name game

The name game

Who decides what to call objects in space?

There are hundreds of objects in space. Who decides what they are called?

Planets and moons in our solar system

Planets and moons in our solar system are all named after Roman and Greek Gods except Earth. For example, Jupiter is the name for the King of the Gods in Roman mythology. A good choice for the largest planet in our solar system!

The word 'Earth' comes from a mixture of Old English and Germanic words meaning ground or soil.


Mars - named after the Roman god of war


Comets are named after the person who discovered them. For example, Halley's comet is named after the astronomer Edmond Halley, who worked out its orbit. Now discoverers are more likely to be solar-observing satellites or automated observatories.

Comet Siding Spring

Comet Siding Spring, discovered by the Siding Spring observatory in Australia


When an asteroid is discovered, it is given a number, such as 2002 AT4. The first bit is the year it was discovered and the second bit is a code showing the month it was discovered. Once an asteroid's orbit is confirmed it is given a number and sometimes a name chosen by the discover. A name is so much more exciting than a number!

Eros Asteroid

Eros 433, the first near-Earth asteroid discovered, named after the Greek god of love

The International Astronomical Union (IAU)

The IAU are in charge of naming all the objects in space. When an someone discovers an object they can submit a suggestion to the IAU. The IAU either approves it or suggests a different name.

The IAU says:

  • Names that are political or military are only allowed 100 years after the event has occured or the person has died.
  • Names of pet animals are discouraged. Fluffy Bunnykins would be a funny name for an asteroid!
  • Commercial and brand names are not allowed.