Close up of Triton, from the Voyager 2 flyby in 1989. [NASA/JLP Space Australia]

Quiz: Naming Names

1. What did Galileo call the four moons he discovered orbiting Jupiter?
(A) called them, as a group, Medici Sidera; (B) used names from Roman mythology; (C) numbered the moons from 1 to 4 in Roman numerals

2. Which contemporary of Galileo named Jupiter's moons?
(A) Johannes Kepler; (B) Simon Marius; (C) Pierre Gassendi

3. Who named Pluto's moon Charon after his wife?
(A) Asaph Hall; (B) Jean-Dominique Cassini; (C) James Christy

4. Which astronomer named his discovery George?
(A) Johann Galle; (B) William Herschel; (C) Le Verrier

5. Which fantasy author gave star names to a family of characters?
(A) C.S. Lewis; (B) J.K. Rowling; (C) J.R.R. Tolkien

6. Who named moons of Uranus for characters from English literature?
(A) John Herschel; (B) William Herschel; (C) Caroline Herschel

7. Giuseppe Piazzi at the Palermo Astronomical Observatory in Sicily was the first person to discover an asteroid. What did he name it?
(A) Astraea; (B)Vesta; (C) Ceres Fernandea

8. Who sent Hope to Mars?
(A) NASA; (B) UAE; (C) ESA

9. Who named Neptune's moon Triton?
(A) Camille Flammarion; (B) William Lassell; (C) Gerard Kuiper

10. Which distant body's name reflected a controversy in the International Astronomical Union (IAU)?
(A) Haumea; (B) Pluto; (C) Eris

Answers and notes

1. What did Galileo call the four moons he discovered orbiting Jupiter? A & C
There are two right answers here. Galileo didn't name the moons, he numbered them using Roman numerals. As a tribute to his patrons, the Medici family, he also called the four moons Medici Sidera (Medici Stars).

2. Which contemporary of Galileo named Jupiter's moons? (B) Simon Marius
German astronomer Simon Marius had also observed the four moons, but Galileo claimed that Marius plagiarised his work. In any case, Galileo had published first, so he got the credit. Interestingly, Marius had named the moons Io, Europa, Ganymede and Callisto. Some 300 years later, these names caught on. By the way, give yourself half a mark if you answered Kepler. He suggested the names to his friend Marius. Pierre Gassendi, a French philosopher, astronomer and mathematician, was not involved in this controversy.

3. Who named Pluto's moon Charon after his wife? (C) James Christy
James Christy, who discovered a moon for Pluto, wanted to name it for his wife Charlene. That, of course, was not permitted. But colleagues noted that the ferryman of the dead in Pluto's realm was Charon. The first four letters of the name made Char, which is what Christy called his wife. Asaph Hall named the moons of Mars, Phobos and Deimos. Jean-Dominique Cassini discovered four of Saturn's moons, but didn't name them.

4. Which astronomer named his discovery George? (B) William Herschel
In 1781, Herschel became the first person to discover a new planet. He named it Georgium Sidus [George's Star] after King George III. This tribute didn't catch on outside Britain, and the new planet was known by various names. Many years later, Johann Bode proposed the name Uranus. Uranus was the father of Saturn. It was 65 years later that Galle found Neptune, using the calculations that Le Verrier had sent him.

5. Which fantasy author gave star names to a family of characters? (B) J.K. Rowling
The Black family in the Harry Potter books had star names. Amongst other books, C.S. Lewis wrote the Narnia chronicles. J.R.R. Tolkien is known for his tales of Middle Earth.

6. Who named moons of Uranus for characters from English literature? (A) John Herschel
William's son John named moons of Uranus for characters from Shakespeare and English poet Alexander Pope. William Herschel gave his planet a name, but not its moons. His sister Caroline observed and recorded, but didn't propose any names.

7. Giuseppe Piazzi at the Palermo Astronomical Observatory in Sicily was the first person to discover an asteroid. What did he name it? (C) Ceres Fernandea
Ceres was the goddess of agriculture and Ferdinand III was the king of Sicily. Although Ceres was acceptable to the rest of the world, King Ferdinand wasn't. So the name was shortened to Ceres. Ceres was considered a planet for over half a century. However, with many more of the small bodies being found, they were given the new classification of asteroid. Ceres is now also classed as a dwarf planet.

8. Who sent Hope to Mars? (B) UAE
NASA's Mars missions are well known, but there are others. The Hope mission sent to Mars by the United Arab Emirates (UEA) arrived at Mars in 2021. ESA, the European Space Agency, currently has two orbiters circling Mars.

9. Who named Neptune's moon Triton? (A) Camille Flammarion
When William Lassell discovered Neptune's moon in 1846, he didn't bother to name it. The planet's only known moon was just called “Neptune's satellite”. Popular French astronomer and author, Camille Flammarion, named the moon Triton in his 1880 book Astronomie Populaire. Triton was a son of Neptune. However, it still didn't need a name until 1949 when Gerard Kuiper discovered a second Neptunian moon, which he named Nereid. The Nereids were sea nymphs.

10. Which distant body's name reflected a controversy in the International Astronomical Union (IAU)? (C) Eris
In 2006 decided to define planets and moons and other bodies. The outcome removed Pluto from the planet category, as well as a recent discovery nicknamed Xena. They were classified as dwarf planets. Fans of Pluto are still annoyed about this. When Xena was given a name, the discovery team chose the Greek goddess Eris. Eris was the goddess of discord. Haumea, a body discovered beyond Neptune in 2004, is another dwarf planet.