Ordering the Solar System Trivia Quiz

The Sun is by far the largest object in the Solar System. In fact, it is so big that more than 1 million Earths could fit inside the Sun's volume! The Sun is a medium-sized star called a yellow dwarf and is about 4.5 billion years old. Plants rely on the Sun's energy to make food and animals depend on the Sun for light and warmth. You should never look directly at the Sun as it can quickly damage your eyes.

Jupiter is the largest planet in the Solar System and is large enough to hold over 1000 Earths within its volume. Jupiter does not have a solid surface so scientists call it a gas giant. It is made almost entirely of the two gases hydrogen and helium (like the sun but much cooler).

As large as Jupiter is, one day only takes 10 hours. Jupiter is famous for its big red spot, which is a storm that is larger than the Earth and has been raging for over 300 years!

Saturn is also a gas giant and, like Jupiter, is made up of hydrogen and helium. Pictures of Saturn show beautiful rings around its equator. The rings are incredibly thin, with an average distance of 10 to 100 meters from top to bottom. Saturn is also the least dense planet in the solar system.

In fact, it is so light that it would float on water if a bathtub were large enough to hold it!

Like Jupiter and Saturn, Uranus does not have a rocky surface. Uranus is called an ice giant with an icy liquid surface of water, methane, and ammonia. This means that not only would Uranus be very cold but also very stinky since ammonia smells like urine or sweat! Yuck! Uranus is also unusual because its axis tilts almost completely over, meaning its poles can face directly toward the sun.

The moons of Uranus are named after characters from William Shakespeare's plays.

Neptune also does not have a rocky surface and is made up of water, methane, and ammonia like Uranus. The vibrant blue color we often see in images of Neptune is inaccurate. The planet looks much more like Uranus, a light teal color. Neptune is the coldest planet in our Solar System and the most distant from the Sun. It takes 165 Earth years for Neptune to go around the Sun once.

Earth is the planet we know best and the only planet in the Solar System where humans can live without a life support suit. Earth is the largest of the terrestrial planets. Terrestrial means having a solid rocky surface. The Earth is in what scientists call the Goldilocks Zone, meaning the temperature is just right for living things as we know them.

The distance from the Sun plus our atmosphere are two big reasons why the temperature on Earth is just right. Liquid water, in particular, is critical for the plants and animals we have on Earth.

Often called Earth's twin, Venus is similar in size to the Earth and is our closest neighbor. However, Venus is very hot with an average surface temperature of 460 degrees Celsius! The atmosphere is made up of thick sulfuric acid clouds that trap heat and significantly increase surface pressure. Venus has several volcanoes that also add to the overall inhospitability of the planet.

Mars is the Earth's other neighbor, being the fourth planet in the Solar System counting out from the sun. Mars is significantly smaller than the Earth, resulting in its gravity being only 38% of what it is on our world. So if a person weighs 100 kg on Earth they would weigh 38 kg on Mars! Besides Earth, Mars is the only other planet in the Solar System that humans have a realistic chance of visiting.

Unfortunately, the atmosphere of Mars is very thin and is mostly carbon dioxide. So humans would have to have a reliable source of oxygen to live on Mars. Also, the lack of an atmosphere on Mars would put any life there at risk of damaging radiation from the Sun. With clever engineering, it is possible to one day colonize Mars!

Mercury is the smallest planet in the Solar System and the closest to the Sun. Mercury has almost no atmosphere because the hot sun blasts away any gasses that come close to the planet. Mercury revolves around the Sun in 88 Earth days, giving it the shortest year in the Solar System, but it takes 176 days for the planet to spin around for one day.

It is estimated that about 75% of Mercury is made up of iron, which makes up the planet's core.

The smallest object on our list is the Moon, although it is larger than all but 4 other moons in our Solar System. The Earth's moon is a very special place. For one, it is the only other object in the Solar System that humans have walked on. Next to the Sun, the Moon is the brightest object in our night sky.

The Moon does not give off its own light, but rather reflects the light from the Sun. The size of the Moon is large enough and close enough to Earth to have a gravitational pull on the ocean tides.

Another amazing fact about the Moon is its distance from the Earth is just right to appear to be the same size as the Sun, to create beautiful eclipses when their paths line up just right.