The New Horizons flyby of Pluto and its satellites returned a scientific treasure trove of information about these distant and surprisingly complex worlds, showing a vast nitrogen glacier as well as ice mountains, canyons, cliffs, craters and more. Now the categories for official names have been approved and the name proposals can be submitted by the New Horizons team.

In 2015, in partnership with NASA’s New Horizons mission and the SETI Institute , the International Astronomical Union (IAU) endorsed the Our Pluto naming campaign, which allowed the public to participate in the exploration of Pluto by proposing names for surface features on Pluto and its satellites that were still awaiting discovery. Each of the system’s six worlds was designated a set of naming themes set out by the IAU’s Working Group for Planetary System Nomenclature (WGPSN). The public responded with overwhelming enthusiasm, suggesting and voting on thousands of names within these categories, as well as proposing names not fitting the approved set of themes.

Working with the New Horizons team, the IAU has agreed to revised naming themes (listed below) for Pluto and its largest moon, Charon. For its four smaller moons — Styx, Nix, Kerberos, and Hydra — the themes remain unchanged. Some of these themes build on the connection between the Roman god Pluto and the mythology of the underworld. Other themes celebrate the human spirit of exploration.

Pluto:
* Gods, goddesses, and other beings associated with the Underworld from mythology, folklore and literature.
* Names for the Underworld and for Underworld locales from mythology, folklore and literature.
* Heroes and other explorers of the Underworld.
* Scientists and engineers associated with Pluto and the Kuiper Belt.
* Pioneering space missions and spacecraft.
* Historic pioneers who crossed new horizons in the exploration of the Earth, sea and sky.

Charon:
* Destinations and milestones of fictional space and other exploration.
* Fictional and mythological vessels of space and other exploration.
* Fictional and mythological voyagers, travellers and explorers.
* Authors and artists associated with space exploration, especially Pluto and the Kuiper Belt.

Styx:
* River gods.

Nix:
* Deities of the night.

Kerberos:
* Dogs from literature, mythology and history.

Hydra:
* Legendary serpents and dragons.

Using the revised themes, the New Horizons team will now propose names for the surface features to the IAU, as the body responsible for the official naming of celestial bodies and their surface features. The IAU’s Working Group for Planetary System Nomenclature will then decide on the formal names.

“I’m very happy with both the process and partnership that New Horizons and the IAU undertook that led to wonderful, inspiring, and engaging naming themes for surface features on Pluto and its moons,” said Alan Stern, New Horizons principal investigator from Southwest Research Institute, Boulder, Colorado. “We look forward to the next step — submitting actual feature names for approval.”

Rita Schulz, Chair of IAU’s WGPSN said, “I am very pleased that the close collaboration of the WGPSN with the New Horizons Team led to these beautiful, inspirational categories for naming the features on Pluto and its satellites. We are ready now for receiving the proposals for names. Good things take time, but it will be worth it.”

Contacts:
Lars Lindberg Christensen
IAU Press Officer
Garching bei München, Germany
+49 89 320 06 761, cell: +49 173 38 72 621
lars@eso.org

Rita Schulz
Chair, IAU Working Group Planetary System Nomenclature
European Space Agency (ESA), Netherlands
+31 71 565 48 21
rschulz@rssd.esa.int

Campaign for Public Participation in Naming Features on Pluto:
https://www.iau.org/news/pressreleases/detail/iau1502/

Pluto satellites naming vote:
https://www.iau.org/news/pressreleases/detail/iau1303/

NASA New Horizons Mission:
http://www.nasa.gov/newhorizons
http://pluto.jhuapl.edu

The IAU is the international astronomical organisation that brings together more than 10,000 professional astronomers from almost 100 countries. Its mission is to promote and safeguard the science of astronomy in all its aspects through international cooperation. The IAU also serves as the internationally recognised authority for assigning designations to celestial bodies and the surface features on them. Founded in 1919, the IAU is the world’s largest professional body for astronomers.