The Weird and Wonderful IAU Naming Conventions

24th November 2016


The IAU is the international organisation which is charge of designating celestial bodies and their features. To assist in the process of naming these objects and features the IAU has developed an incredible list of rules and conventions. Here are just a few of these, sometimes odd, rules. Enjoy!

1) No names should have political, military or religious significance. There are some exceptions to this rule though such as pre-19th century politicians

2) All the features on the planet Venus must be named after a woman. For example, the dunes on the planet are named after sky goddesses. The only exceptions to this rule are the features that were named before this convention came about

3) The features on Saturn’s moon Enceladus are all named after characters and locations from Richard Burton’s translation of “The Book of One Thousand and One Nights” (Arabian Nights).

4) Commemoration of persons is allowed but the person must have been internationally significant and been deceased for at least 3 years.

5) Colles (collections of small hills) on Saturn’s moon titan are all named after characters from the J.R.R Tolkien’s fictional world of Middle Earth.

6) All the valleys on Mercury are named after abandoned towns and cities from antiquity

7) Craters which are 60km or smaller on Mars are all named after towns on Earth with a population of 100,000 people or less. The IAU states though that this isn’t intended to be commemorative but is just because it’s a large source of names! It does mean that are some fantastic names though such as the Porth crater.

8) Religious names are allowed when the religion is dead or not widespread. This is why all of the planets in the solar system – except for Earth – are named after Roman gods.

9) All the valleys which are more than 400km on Venus are named “Venus” (in various languages) and valleys less than 400km are named after river goddesses

10) Features which measure less than 100 meters aren’t typically named though they do often get unofficial names. They are for example rocks on Mars named everything from “Poptart” to “Indiana Jones” and “Scooby Doo”.

11) All the large ringed structures on the Jovian moon Europa are named after Celtic stones circles.

12) All the features on Saturn’s moon Mimas are named after characters and location’s from  Thomas Malory’s “Le Morte d’Arthur” legends.