50 free Haumea trivia questions with answers — science & nature quiz, new questions added Aug 2026.
This Haumea trivia quiz covers the strangest of the dwarf planets: a body the length of Pluto and half as tall, spinning once every four hours, wrapped in crystalline ice, ringed, and trailing a family of fragments from an ancient collision. It starts with the tangled discovery, Mike Brown's Caltech team finding it just after Christmas 2004 and nicknaming it Santa, José Luis Ortiz's Spanish team announcing first from 2003 images, the accusation over accessed observation logs, and the IAU's Solomon-like choice of the Hawaiian name over Ataecina. The science section covers the egg shape and what would happen if it spun faster, the 2017 stellar occultation that revealed the first ring beyond Neptune, the snow-bright surface and its dark red spot, the moons Hiʻiaka and Namaka once called Rudolph and Blitzen, the 285-year orbit and 7:12 resonance with Neptune, the collisional family and the distant looks New Horizons has taken. It ends with the mythology: the fertility goddess whose children sprang from her body, her daughter Pele the volcano goddess, and the patron of hula. Difficulty runs from easy to expert and is shown on each question, so it suits a classroom, a pub quiz or a space enthusiast. Every answer was checked against a reference page and each question carries its citation. Try our Pluto, Eris and Solar System quizzes for more.
30 of 50 questions with answers and explanations. Play the quiz
Q 01Where in the Solar System is the dwarf planet Haumea?
Beyond Neptune, in the Kuiper belt
It is the third-largest known trans-Neptunian object after Eris and Pluto, about the size of Uranus's moon Titania.
Q 02Haumea is named after a goddess from the mythology of which Pacific islands?
Hawaii
The Caltech team chose the names to honour Mauna Kea, where the moons were found.
Q 03The goddess Haumea presides over what?
Childbirth and fertility
Her many children were said to spring from different parts of her body, an apt image for a body that shed a family of fragments.
Q 04What is Haumea's most unusual physical feature?
An elongated, egg-like ellipsoid shape
Its long axis is roughly twice its short one, thanks to a spin of under four hours.
Q 05How long does Haumea take to rotate once?
About 3.9 hours
Faster than any other known body in equilibrium; a little quicker and it would split into a dumbbell.
Q 06If Haumea rotated much faster than it does, what is the predicted result?
It stretches into a dumbbell and splits in two
The current spin is thought to be a leftover of the giant impact that made its moons and family.
Q 07What was discovered around Haumea in 2017, a first for any object beyond Neptune?
A ring
It showed up in a stellar occultation on 21 January 2017 and was reported in Nature that October.
Q 08Roughly what is the radius of Haumea's ring?
About 2,287 km
It is about 70 km wide and sits well within Haumea's Roche limit.
Q 09How many moons does Haumea have?
Two
Both were found in 2005 with the Keck telescopes and are named after daughters of the goddess.
Q 10What are Haumea's two moons called?
Hiʻiaka and Namaka
Both are daughters of the goddess Haumea; the Caltech team first nicknamed them Rudolph and Blitzen.
Q 11What festive nicknames did the discovery team first give Haumea and its two moons?
Santa, Rudolph and Blitzen
Haumea was found on 28 December 2004, just after Christmas.
Q 12Which moon of Haumea, the larger and outer one, was nicknamed 'Rudolph'?
Hiʻiaka
About 310 km across, it circles Haumea every 49 days and is coated in crystalline water ice.
Q 13Which team leader from Caltech discovered Haumea in December 2004?
Mike Brown
The same team found Eris and Makemake, and Brown wrote 'How I Killed Pluto and Why It Had It Coming'.
Q 21What large feature was spotted on Haumea's bright white surface in 2009?
A dark red spot
Possibly an impact scar rich in minerals and organic compounds.
Q 22Haumea's mass is roughly what fraction of Pluto's?
About one-third
That is 1/1400 of Earth's; nearly all the system's mass is in Haumea itself.
Q 23According to a 2019 model, Haumea's dimensions are roughly what?
2,100 × 1,680 × 1,074 km
Its long axis is about the diameter of Pluto; its poles are only about half that apart.
Q 14Which Spanish astronomer's team announced Haumea first, in July 2005, using 2003 images?
José Luis Ortiz Moreno
Brown then discovered the Spanish observatory had accessed his online logs the day before, and cried foul.
Q 15What did the Caltech team leader accuse the Spanish team of doing before their announcement?
Accessing his observation logs online
Ortiz admitted looking at the logs but denied wrongdoing, saying he was checking whether Caltech had a new object.
Q 16What provisional designation did Haumea carry before it was named?
2003 EL61
The '2003' reflects the date of the Spanish team's discovery image, not Caltech's 2004 one.
Q 17What name did the Spanish team propose for the dwarf planet, which the IAU rejected in 2008?
Ataecina
An Iberian underworld goddess; underworld names are reserved for plutinos, and Haumea is not one.
Q 18How did the IAU rule on who discovered Haumea?
The credit went to no one, but the Caltech names were used
The naming choice was seen as siding with the Caltech team without formally awarding discovery.
Q 19Haumea's surface is covered mostly in what?
Crystalline water ice
Odd, because crystalline ice should not form or survive at 50 K under cosmic-ray bombardment.
Q 20Haumea's albedo of 0.6 to 0.8 makes it about as reflective as what?
Snow
Best-fit models make 66% to 80% of the surface pure crystalline water ice.
Q 24How long does Haumea take to orbit the Sun?
About 285 years
It passed aphelion in 1992 and will reach perihelion in 2133.
Q 25Haumea is thought to be in an intermittent orbital resonance with Neptune of what ratio?
7:12
The resonance switches on and off twice every 4.6-million-year precession cycle.
Q 26Haumea's high albedo, fast spin, rings and moons are all thought to result from what?
A giant collision
The impact stripped much of its ice mantle and scattered a family of icy fragments.
Q 27Haumea is the largest member of what, the first of its kind identified beyond Neptune?
A collisional family
Members such as 2002 TX300 share its orbit and icy surface, all fragments of one shattered ancestor.
Q 28Which spacecraft observed Haumea from afar in 2007, 2017 and 2020?
New Horizons
Its outbound path let it view Haumea at phase angles impossible from Earth.
Q 29How bright is Haumea as seen from Earth?
Magnitude 17.3, third-brightest Kuiper belt object
Only Pluto and Makemake outshine it in the Kuiper belt; a large amateur telescope can pick it up.
Q 30Precovery images of Haumea have been identified as far back as which year?
1955
Nobody noticed it in the old plates until they knew where to look.