Minor-planet designation

Minor planets are small objects that orbit the Sun, like asteroids and dwarf planets. They have special names and numbers to help scientists study them. The Minor Planet Center gives each minor planet three important labels.

First, a minor planet gets a provisional designation when it is found. This name shows the date it was discovered.

Later, once scientists know its path around the Sun very well, it receives a permanent number. This number is used to keep track of the object.

Some special minor planets also get a proper name, like Ceres or Pluto. These names are used alongside their numbers.

The Minor Planet Center also helps with studying comets and other objects visiting our Solar System, but they use different naming rules for those.

Summary

When a new space rock is found and reported to the Minor Planet Center, it gets a special temporary label called a provisional designation. This label shows when it was discovered. Once scientists are sure where the space rock will go, it gets a permanent number. This number helps everyone know exactly which space rock is being talked about.

Only a small part of these space rocks have special names. The person who finds the rock can suggest a name, but it has to be approved and must be unique. Out of nearly a million space rocks with numbers, only about twenty six thousand have names. As more space rocks are found, even fewer will get names.

Syntax

When we talk about small planets in space, scientists use special names to keep track of them. If a small planet is first found, it gets a temporary name based on the date it was seen. Once its path around the Sun is known for sure, it gets a permanent number.

Sometimes, a small planet also gets a special name. To make things clear, scientists might use all three — the temporary name, the number, and the special name — together. Different groups of scientists write these names in slightly different ways, but they all mean the same thing.

For example, a small planet found in 2006 might be called [2006 DP14](/wiki/2006_DP14) at first. If later it gets the number 388188, it could be written as (388188) 2006 DP14. If it also gets a name like Wikipedia, it might be written as (274301) Wikipedia.

Satellites

Small planets sometimes have even smaller planets orbiting them, called satellites. These don’t always get names right away. When a satellite’s path is known, it gets a special temporary name that includes the year it was found and the name of the small planet it orbits. For example, the first satellite found around the small planet Sylvia in 2001 was called S/2001 (87) 1.

Some satellites also get Roman numerals (like I or II) as part of their permanent names. Sylvia’s satellites were named Romulus and Remus, and are sometimes called (87) Sylvia I Romulus and (87) Sylvia II Remus.

History

Minor planets were first identified by female classical names and special symbols, similar to the major planets. By 1851, there were fifteen known asteroids, each with its own symbol. As more objects were discovered, the symbols became too complicated, so a new system was introduced.

Astronomer Benjamin Apthorp Gould suggested numbering asteroids in the order they were found and using a number inside a circle as a symbol. This made things easier to write and read. Over time, the system changed again, and today we use numbers and names to identify minor planets. The current way of giving temporary names to newly found minor planets started in 1925.