Students help name 5 of Jupiter’s newly discovered moons | Science News for Students

Students help name 5 of Jupiter’s newly discovered moons

The monikers, in keeping with tradition, come from Greek and Roman mythology
Sep 20, 2019 — 6:45 am EST
the planet Jupiter, as seen from NASA's Juno spacecraft

Jupiter, shown in an image from NASA’s Juno spacecraft, has 79 moons. Five recently spotted ones have just gotten their official names.

JPL-Caltech/NASA, SwRI, MSSS, Kevin M. Gill

Meet the newly discovered moons of Jupiter. After a public contest, five of them finally have official astronomical names. The International Astronomical Union announced the names on August 26.

Scott Sheppard is a planetary scientist at the Carnegie Institution for Science in Washington, D.C. He reported the discovery of these five moons in July 2018 along with seven others. He and his colleagues spotted the Jovian satellites while searching for Planet Nine. Planet Nine is a suspected planet that may be orbiting beyond Neptune. To date, no one has seen it.

The team solicited candidate names for the moons on Twitter. There were some rules. Most notably, each of Jupiter’s 79 known moons must be named for descendants or consorts of the god Jupiter (from Roman mythology), or Zeus (in Greek myths). But that didn’t stop people from suggesting the names of beloved pets. And, somewhat inevitably, someone suggested Moony McMoonface.

Here are the winners:

Pandia: She’s the goddess of the full moon. Pandia is the daughter of Zeus and the moon goddess Selene. One group that entered this name in the contest was the astronomy club of the Lanivet Community Primary School in Bodmin, England. The school’s mascot is a panda.

Ersa: Sister of Pandia, Ersa is the goddess of dew. Several people suggested this name. They included 4-year-old moon expert Walter. He got the judges’ attention with a song listing the largest moons of the solar system in order of their size.

Eirene: The goddess of peace, Eirene is the daughter of Zeus and Themis, a Greek Titaness who personifies divine order, justice and law. Among the tweets that suggested this name was one submitted on behalf of a mythology-loving 10-year-old.

Philophrosyne: Philophrosyne is the spirit of welcome and kindness. She’s a granddaughter of Zeus. Among the submitters of this name was an 11th-grade history class.

Eupheme: Sister of Philophrosyne, Eupheme is the spirit of praise and good omens.

Power Words

(more about Power Words)

astronomy     The area of science that deals with celestial objects, space and the physical universe. People who work in this field are called astronomers.

colleague     Someone who works with another; a co-worker or team member.

descendant     A blood relative of a person who lived during a previous time.

Jupiter     (in astronomy) The solar system’s largest planet, it has the shortest day length (10 hours). A gas giant, its low density indicates that this planet is composed of light elements, such as hydrogen and helium. This planet also releases more heat than it receives from the sun as gravity compresses its mass (and slowly shrinks the planet).

moon     The natural satellite of any planet.

Neptune     The furthest planet from the sun in our solar system. It is the fourth largest planet in the solar system.

new moon     The phase of the moon that appears fully dark, when viewed from Earth. At this time, the moon will sit between the earth and sun. So the lunar face lit by the sun is turned away from us. 

planet     A celestial object that orbits a star, is big enough for gravity to have squashed it into a roundish ball and has cleared other objects out of the way in its orbital neighborhood. To accomplish the third feat, the object must be big enough to have pulled neighboring objects into the planet itself or to have slung them around the planet and off into outer space. Astronomers of the International Astronomical Union (IAU) created this three-part scientific definition of a planet in August 2006 to determine Pluto’s status. Based on that definition, IAU ruled that Pluto did not qualify. The solar system now includes eight planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune.

satellite     A moon orbiting a planet or a vehicle or other manufactured object that orbits some celestial body in space.

solar system     The eight major planets and their moons in orbit around our sun, together with smaller bodies in the form of dwarf planets, asteroids, meteoroids and comets.

tweet     Message consisting of 140 or fewer characters that is available to people with an online Twitter account.

Twitter     An online social network that allows users to post messages containing no more than 280 characters (until November 2017, the limit had been just 140 characters).


Statement: International Astronomical Union. Public contest successfully finds names for Jupiter’s new moons. August 26, 2019.

Statement: Carnegie Institution for Science. The results are in! Jovian moon-naming contest winners announced. August 23, 2019.