Moons in our Solar System Trivia Quiz

Answer: Mercury and Venus

Most of the planets and dwarf planets in our solar system have moons. However, neither Mercury nor Venus have their own natural satellite. Astronomers have a few theories about how moons come to be. Some feel that they are large space rocks that have been floating around and are captured by a planet's gravitational pull.

Another theory is that a large object smashes into the planet at one time, with the resulting debris forming a moon. Finally, others theorize that moons form by coming together a bit at a time, slowly accumulating layers of material.

In the case of Venus, some scientists theorize that it once did have a moon that was caused by being smashed by a large chunk of space rock, and that it was slowly drifting away from the planet.

Then, Venus was smashed again. This, according to the scientists, resulted in Venus reversing its spin which resulted in the planet attracting its moon until there was a collision between the two that destroyed the moon. Of course, this is all theory, but it does sound like a good explanation for why Venus does not have a moon and spins in the opposite direction than all other planets in our solar system.

Answer: 5th

The Earth's moon is our only natural satellite. It is the fifth largest moon in the solar system, and is about 240,000 miles (385,000km) away from the Earth. The Moon helps to keep our planet steady on its axis, which in turn prevents it from wobbling and stabilizes our climate.

It is thought that the Moon got its name in medieval times before Galileo made his observations of other moons in the solar system. In medieval times, people simply thought that it was the only moon anywhere.

Answer: Uranus

If they are named, most of the moons in our solar system are named after characters in Greek or other mythologies. However, Uranus is a bit different. The 27 moons there have been given the names of Shakespearean characters and, more recently, characters from Alexander Pope.

Some of the names of the Uranus moons include Juliet ("Romeo and Juliet"), Cordelia ("King Lear"), Ophelia ("Hamlet"), and its largest moon Titania ("A Midsummer Night's Dream"). More recently, moons have been named after characters in "The Rape of the Lock" (a poem by Alexander Pope).

These include Ariel, Umbriel, and Belinda.

Answer: Haumea

Haumea is a dwarf planet that is located in the Kuiper Belt. It is about the same size as Pluto, and is one of the the fastest spinning objects in our solar system. In fact, the speed of its spin has distorted its shape so that it is not spherical, but is more oval-shaped like an American football.

When Haumea is compared to Earth in size, astronomers say that if Earth were a nickel (coin), Haumea would be as small as a sesame seed. Little is known of this dwarf planet or its moons because of its distance away from the Earth.

However, scientists do know that it takes 285 Earth years for Haumea to make one orbit of the sun, and that it does have rings, as evidenced by observations that were made as the dwarf planet moved across the path of light coming from a star. Haumea is the Hawaiian goddess of fertility.

In 2005, two moons were discovered orbiting around this dwarf planet, Namaka and Hi'iaka. The names are taken from the daughters of Haumea. The goddess of the island of Hawaii is Hi'iaka.

She is also known as the goddess of hula dancers. In Hawaiian stories, Namaka is a water spirit.

Answer: Asaph Hall

Astronomer Asaph Hall discovered Mars' moons in 1877. He was apparently frustrated with his search for the moons, and wanted to give up until his wife suggested that he continue. He found the first moon Deimos the next night. Then, he found Phobos six nights later.

The moons of Mars are the smallest in our solar system. Phobos sits only 3,700 miles (6,000 kilometers) above the surface of the planet. Phobos orbits around Mars three times every 24 hours, while Deimos takes 30 hours to orbit its planet once. Phobos is slowly being pulled toward Mars, travelling about six feet (1.8 metres) closer to the planet every Earth year. Astronomers estimate that Phobos will eventually either crash into Mars, or break up and create a ring of dust around the planet.

This won't happen in our lifetime, though. They estimate that this will occur in about 50 million years.

Answer: 79

In 2017, a group of scientists was searching for planetary bodies at the outer edge of our solar system. Jupiter just happened to get in the way of their observations and that's when they discovered the twelve new moons. The qualities of eleven of the moons suggest that they were once part of larger bodies that broke apart when struck by other moons or objects such as asteroids.

The astronomers are calling the twelfth moon an "oddball" moon because it is likely the smallest of Jupiter's moons (about 1.6 km, or 1 mi diameter), and it has an orbit unlike the other moons of Jupiter.

Other moons of Jupiter include Io, the most volcanically active body in our solar system, Europa, which is covered with potentially life-supporting ice, Ganymede, the largest moon in our solar system (it is larger than Mercury), and Callisto, with its many craters. Io, Europa, Ganymede, and Callisto were discovered by Galileo Galilei in 1610.

Answer: Charon

By 2021, scientists had recognized that Pluto had five moons. Charon is by far the largest of them. It was discovered in 1978, and is approximately half the size of the planet itself. The remaining planets are Hydra, Nix, Styx, and Kerberos. Astronomers suggest that all of Pluto's moons were formed when the dwarf plant collided with a space object such as an asteroid or a comet.

The resulting debris was then taken in by Pluto as moons that orbit the dwarf planet.

Answer: True

Eris is a dwarf planet that was discovered in 2005. At first, even though it was further from the sun, it appeared to be larger than Pluto. However, astronomers were able to complete further observations of the dwarf planet in 2010 that showed that Eris is actually smaller than Pluto. Eris has at least one moon which is named Dysnomia, the daughter of the Greek goddess Eris. Given its distance from the Earth, observations of Dysnomia have been limited. Scientists have estimated its diameter to be 700 ± 115 km (435 ± 72 mi).

Answer: Titan

Titan is an amazing moon. It has an atmosphere similar to Earth's, which is made up mostly of nitrogen. It also has plenty of water on its surface, with seas and rivers beneath a crust of ice. It is larger than the planet Mercury, and is the second largest moon in our solar system with Ganymede, one of the moons of Jupiter, being slightly bigger. Scientists suggest that Titan could one day be a living space for humans. Rhea is the second largest moon of Saturn, but still less than a third the size of Titan. Saturn has a number of moons that are not rounded in shape. Hyperion is Saturn's largest non-spherical moon. Prometheus is shaped like a potato, and scientists theorize that it may be a porous, icy body.

Answer: An egg-shaped orbit, with Neptune close at one phase and far away at another

Nereid is known to astronomers to have a really odd orbit. They call it an eccentric orbit because although it orbits in the same direction as the planet Neptune, it goes in an egg-shaped path, with Neptune close at one end and far away at the other. Scientists have measured that its path brings it as close as 1,372,000 km (853,000 mi) at one point, and as far as 9,655,000 km (5,999,000 mi) at the opposite end of its orbit.

In 1989, the space probe Voyager 2 took photos which showed that Nereid is grey in colour.