How do scientists name solar system objects, and why do some names sound mythological while others look like code?
The answer involves astronomy, history, and strict naming rules that keep the Solar System organized.
Why naming solar system objects matters
Scientific names are not just labels for convenience.
They help astronomers, planetary scientists, and observatories identify objects precisely in catalogs, research papers, and mission planning.
The Solar System contains millions of known objects, including planets, dwarf planets, moons, asteroids, comets, trans-Neptunian objects, and meteoroid populations.
Without standardized naming, it would be difficult to distinguish one body from another across languages and research databases.
- Reduce confusion between similar discoveries
- Support international scientific communication
- Record discovery order and object type
- Preserve historical and cultural naming traditions
Who decides the names?
The International Astronomical Union, or IAU, is the main authority that approves official names for most solar system bodies.
Founded in 1919, the IAU sets naming standards used by astronomers worldwide.
Different IAU groups handle different categories.
The Working Group for Planetary System Nomenclature manages names for surface features, moons, and many small-body designations.
For exoplanets, stars, and some other objects, separate naming processes exist, but within the Solar System the IAU is central.
Discovery teams often propose names, but approval depends on established rules.
This ensures names are consistent across catalogs used by NASA, ESA, observatories, and research institutions.
How do scientists name solar system objects?
Scientists usually begin with a provisional designation, then move to a permanent name if the object warrants one.
The exact path depends on the object’s class, orbit, and significance.
For example, a newly discovered asteroid may first receive a temporary designation based on the year and sequence of discovery.
If its orbit becomes well established, it can later receive a numbered designation and, optionally, a name chosen under IAU rules.
Major objects such as planets and many moons have established names from mythology, literature, or historical tradition.
Smaller bodies often follow structured naming conventions tied to object type.
Provisional designations: the first step
Before an object receives a permanent name, astronomers assign a provisional code.
This code helps track the object while additional observations confirm its orbit.
Common examples include:
- Asteroids: year of discovery plus letters and numbers, such as 2024 AB
- Comets: designations that can indicate discovery year and type, such as 1P/Halley for periodic comets
- Moons and satellites: temporary identifiers until formal approval
These designations are functional rather than poetic.
They are especially important when dozens or hundreds of objects are discovered in the same survey, such as with modern sky surveys and space telescopes.
Permanent names for planets and dwarf planets
The eight planets received names long before modern astronomy, so their naming history is cultural rather than procedural.
Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune all have names tied to Roman or classical tradition, except Earth, which comes from Germanic and Old English roots.
Dwarf planets also follow established conventions.
Pluto was named in 1930 through a public suggestion process.
Other dwarf planets, such as Eris, Haumea, and Makemake, were named after mythological figures associated with their discoverers’ naming themes.
The IAU has specific expectations for dwarf planet naming, but these names often reflect cultural diversity and mythological heritage.
The goal is to avoid duplication while maintaining meaningful connections to astronomy.
How moons get their names
Moons are often named after mythological characters linked to the parent planet.
This convention creates an organized theme that helps scientists recognize the system at a glance.
Examples include:
- Jupiter’s moons: names from Greek and Roman myth, such as Io, Europa, Ganymede, and Callisto
- Saturn’s moons: names from various mythological traditions, including Titan, Enceladus, and Rhea
- Uranus’s moons: names from Shakespeare and Alexander Pope, such as Titania, Oberon, and Miranda
- Neptune’s moons: names related to sea deities, such as Triton and Nereid
Many newly discovered moons were first tracked with temporary labels like S/2010 J 1, which indicates a satellite discovered in 2010 around Jupiter.
Once confirmed, the object may receive a formal name approved by the IAU.
Asteroids and minor planets: numbers, then names
Asteroids, also called minor planets, follow one of the most structured naming systems in astronomy.
After discovery and orbit confirmation, an asteroid receives a permanent number.
Only then can it be named.
For example, the asteroid Ceres is also designated 1 Ceres because it was the first asteroid discovered.
Thousands of other asteroids have similar numbered identities, and many also have names chosen by the discoverer within IAU guidelines.
Common rules include:
- Names should not be offensive or overly similar to existing names
- They must be pronounceable in multiple languages
- They should not be primarily commercial or political in nature
- Some asteroid families have themed naming sets
Asteroid naming can honor scientists, artists, places, or cultural figures, but the IAU reviews each proposal to ensure it fits nomenclature standards.
Comets and their naming conventions
Comets often carry the names of their discoverers, which is why terms like Halley’s Comet are so well known.
The naming format can also include a prefix that identifies the comet’s orbit type.
Examples of comet naming elements include:
- P/ for periodic comets
- C/ for non-periodic or long-period comets
- X/ for comets with uncertain orbits
If multiple astronomers or surveys discover the same comet independently, the name may reflect more than one discoverer.
Modern automated surveys, including those using CCD imaging and large sky-monitoring programs, have made comet naming more complex than in the past.
What naming rules does the IAU use?
The IAU tries to balance scientific clarity with cultural sensitivity and historical continuity.
Its naming rules vary by object type, but some principles are consistent across categories.
Common IAU naming principles
- A name must not duplicate an existing solar system name
- It should be suitable for international scientific use
- It must avoid commercial branding and political propaganda
- It should follow category-specific themes when required
- It often reflects mythology, literature, or history
These rules help maintain a stable nomenclature that can last for decades or centuries.
Because astronomical catalogs are global, a name has to work well across languages, databases, and mission archives.
Do scientists ever use informal names?
Yes, especially during the early stages of discovery.
Astronomers may use nicknames, survey codes, or internal labels before official approval.
Mission teams also sometimes use informal names for landmarks, such as mountains, craters, and valleys on Mars, Titan, or the Moon.
However, informal names are not the same as official names.
Public nicknames can appear in press releases or mission blogs, but the IAU remains the standard for formal planetary nomenclature.
Mission-specific naming themes are common.
NASA rover teams, for instance, often use place names or memorial themes for drive targets and rocks.
These labels are practical for operations, even if they are not permanent scientific names.
How surface features get named
Not only whole bodies but also craters, valleys, plains, and mountains on planets and moons receive names.
These surface-feature names usually follow themes linked to the body itself.
Examples include:
- Mercury features named after artists, authors, and musicians
- Venus features named after women, especially mythological or historical figures
- Mars craters and valleys named from classic or local traditions
- Pluto features named from mythology, exploration, and underworld themes
These naming patterns help researchers organize maps and compare geological structures across missions such as Voyager, Cassini, Galileo, New Horizons, and Mars orbiters.
Why naming can take time
Approval can take months or even years because astronomers need enough data to confirm an object’s orbit, classification, and uniqueness.
For small bodies, an object may be observed over multiple oppositions before a permanent number or name is assigned.
Some names are delayed until after publication, peer review, and official cataloging.
This careful process reduces errors and keeps the scientific record stable.
In large discovery programs, the pace of detection is faster than the pace of naming.
Surveys like Pan-STARRS, Catalina Sky Survey, and the Dark Energy Survey can identify many candidates quickly, but formal naming remains selective and rule-based.
How scientists name solar system objects today
Modern astronomy combines automated detection, international coordination, and long-standing tradition.
The result is a naming system that is both technical and meaningful.
When people ask how do scientists name solar system objects, the short answer is: they use provisional designations first, then official names approved under IAU rules, usually after orbit confirmation and classification.
The details vary by object type, but the goal is always the same: create clear, unique, durable names for a crowded and expanding Solar System.