How Well Do You Really Know the Solar System?



By: Heather Cahill

6 Min Quiz

Image: Shutterstock

About This Quiz

"My Very Educated Mother Just Served Us Nine Pizzas." I don't think so. If you know anything about the solar system, you'd know to take pizzas out of this sentence! From the sun and moon to the planets, how well do you know the solar system?

When it comes to the solar system, we've all had a lesson in our science class about it. We'd focus on the sun, the moon, the planets, and all that surround them in the sky. Your class probably told you about Claudius Ptolemy who thought the Sun revolved around the Earth. He was debunked by Nicolaus Copernicus who proved that the Sun was the center of the universe and all the objects in the solar system revolved around it. Do you know these basics? It's a good start, but there's more!

Do know how many planets lie in the solar system and which one was "demoted" to a dwarf planet? Can you tell the difference between a comet, asteroid, or meteor? Do you know how gravity works in outer space? 

Most students had to create a diagram of the solar system in their lifetime, but how well do they really know it? How well do you know it?

Are you ready to launch into outer space with this quiz? Will your answers take you from planet to planet or will you be left floating aimlessly?

Let's find out!

Which of the following was once considered a planet but has since been demoted?

Pluto was once considered a planet, but it was demoted in 2006. It is now considered a dwarf planet, and since its discovery, an even larger dwarf planet called Eris has been discovered.


What is a comet made of?

Comets are mostly made of ice and dust, among a few other gases and chemicals. This is why they take on the nickname "dirty snowballs."


Which of the following is not an inner planet?

Neptune is not an inner planet. Neptune is part of the outer gas giants. The inner planets are Venus, Mercury, Mars and Earth.


Which of the following is not an outer planet?

Earth is not one of the outer planets; it is one of the inner planets. The outer planets are Saturn, Jupiter, Neptune and Uranus.


Which of the following is a dwarf planet?

Eris is a dwarf planet. It is the largest of all of the other dwarf planets. There are only five recognized dwarf planets and many more that have yet to be recognized.


Which planet's rings are the most visible?

Saturn's rings are the most visible. Jupiter, Uranus and Neptune all have rings as well, but theirs are not as visible as Saturn's.


What is the only planet known to sustain life?

Earth is the only planet in the solar system that is known to sustain life. There is a possibility that other planets could sustain life as well.


Which planet is shrinking?

Mercury is shrinking. The constant shrinking that the planet has endured has caused wrinkles on its surface. The planet has also lost a fair amount of heat.


Is it true or false that we live inside of the Sun's atmosphere?

It is true that we live inside of the Sun's atmosphere. The Sun's atmosphere goes even farther than the Earth and has other planets orbiting inside of it.


What is the largest moon in the solar system?

Ganymede is the largest moon in the solar system. The moon belongs to Jupiter, and it is made up of ice and rock. It takes ninth place out of the largest objects in the solar system.


What is the largest planet in the solar system?

The largest planet in our solar system is Jupiter. The planet is one of the gas giants, and therefore it is made up of gases such as helium.


Which planet is on its side?

Uranus is on its side. The planet spins on a 98-degree angle. There are many theories as to why the planet spins on its side, but nothing has been proven as of yet.


Which planet experiences powerful winds?

Neptune experiences powerful winds. The winds can reach extreme speeds of up to 1,200 miles per hour which makes them much more powerful than what we experience here on Earth.


What orbits Earth?

The moon orbits Earth. The moon stays in the Earth's orbit because of a gravitational pull that the Earth has; this keeps the moon orbiting our planet.


What is the smallest planet in the solar system?

Mercury is the smallest planet in our solar system. On top of being the smallest planet, it is also shrinking. When Pluto was a planet, it was considered the smallest planet in the solar system.


Which of the following surrounds the Earth?

The Van Allen Belt surrounds the Earth. In short, the Van Allen Belt is radiation that surrounds the planet; there are two probes that were sent up to learn more about the belt.


What does each planet, except for Venus and Mercury, have?

Each planet except for Venus and Mercury has a moon. A few of the planets have many moons while our planet only has one.


What is on Saturn?

There is a hexagonal storm on the planet of Saturn. The storm is located to the North of the planet and has changed colors many times over the many years that it has been active.


How many planets are in the solar system?

There are eight planets in our solar system. These planets are Mercury, Venus, Jupiter, Mars, Earth, Neptune, Uranus and Saturn.


What is at the core of the Sun?

Hydrogen is at the core of the Sun. The hydrogen is what gives the Sun all of the energy that it has to create light and warmth.


Is it true or false that the Sun is a star?

It is true that the Sun is a star. A star has objects orbiting it and because the sun is at the center of all the planets, it is considered to be a star.


What do the planets in the solar system orbit?

The planets in the solar system orbit the Sun. The Sun is at the center of our solar system and creates light and warmth for the planets surrounding it.


Which planet spins the fastest?

Jupiter is the fastest spinning planet. A day on Jupiter only lasts for 10 hours as that is how long it takes for the planet to make its rotation.


When was the solar system formed?

The solar system was formed 4.6 billion years ago. No one is exactly sure on how the solar system we know today was formed, but it is thought that there was a large explosion and gravity pulled together the dust and remnants of the explosion creating our solar system.


Where is the Oort Cloud?

The Oort Cloud is found near the edge of the solar system. It is thought that the cloud is where many comets were created.


Which planet spins in the opposite direction?

Venus spins in the opposite direction of the other planets. Since it spins differently from the other planets, the sun rises in the west and sets in the east on Venus!


What is the largest dwarf planet in our solar system?

Eris is the largest dwarf planet in our solar system. It is even larger than Pluto, which was demoted from being a planet in the year of 2006.


How many Earth days is one day on Venus?

One day on Venus is 116 days on Earth. It takes this long for one day to pass because of the planet's slow rotation. It also takes over 200 Earth days to make an orbit around the Sun.


What created asteroids?

The formation of the solar system created asteroids. Asteroids come in many different shapes and sizes and orbit the Sun the same way that our planets do.


Is it true or false that you weigh less on the moon?

It is true that you weigh less on the moon. The moon has less gravity than we do here on Earth. You can do a lot of things on the moon that you might not pull off on Earth!


Where is the asteroid belt?

The asteroid belt is in between the orbits of Mars and Jupiter. There are countless asteroids located in the belt, mostly in the main area.


Which planet is the hottest?

Venus is the hottest planet. The planet is able to keep in its heat because of its thick atmosphere. It acts as insulation around the planet.


Which of the following planets is not made out of hydrogen and helium?

Earth is not made out of hydrogen and helium. Neptune, Uranus, Jupiter and Saturn are all made out of these chemicals. They form the outer gas giants.


What takes up the most space in the solar system?

The Sun takes up the most space in the solar system; it is the largest object in the solar system and takes up almost all of the space.


How long does it take for sunlight to make it to the Earth?

It takes the sunlight eight minutes to make it to the Earth from the Sun. The Earth is over 90 million miles from the Sun so the light has to travel quite a long way!


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