159 Fun Solar System Facts for Kids (Explore Planets & Space)

Have fun learning over 150 solar system facts for kids! These facts about the solar system are categorized in such a way that you can practice memorizing things about each planet, as well as the sun, moon, comets, asteroids, and more.

You can use the lists of interesting solar system facts for all sorts of learning adventures, be it trivia, copywork, or quizzing. There’s even a free planet fact card set you can download.

Solar System Facts for Kids

Kids are often fascinated with the solar system and the heavenly bodies in the night sky. There are many things about the solar sytem we have yet to learn about, however what we do know is quite astounding.

If you are learning about space and the solar system, these solar system facts for kids will come in handy. You can use them as trivia or just weave them into your study of space.

You can also explore facts about astronauts and learn about space missions. There’s just so much to discover about this topic. You can even download some free planet fact cards. 

Are you ready? Let’s dive in!

What is the Solar System?

The solar system is a collection of planets, moons, asteroids, and comets that orbit around the sun. It includes our own planet Earth along with other planets of our solar system like Mercury, Venus, Mars, Jupiter, Saturn, Uranus, and Neptune. The sun is at the center of the solar system and provides light and heat to all these objects.

What Makes up the Solar System?

The solar system consists of the sun, eight planets (Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune), numerous moons orbiting these planets, asteroids belt between Mars and Jupiter, and the Kuiper Belt beyond Neptune.

Facts About the Solar System

Since there are so many different facts about the solar system, we are breaking it all up in various categories to make it easier to study through. We’ll start with fascinating facts about the solar system planets.

Planet Facts for Kids

There are 8 full-size planets in our solar system, however scientists cannot agree whether or not Pluto is a planet or a dwarf planet. We’ve decided to include it in our list to make learning about planets easier.

Read on to learn interesting things about the planets.

Mercury Facts

1. Mercury is the closest planet to the sun.
2. It is named after the Roman messenger god because of its fast orbit around the sun.
3. Mercury has a very thin atmosphere and no moons.
4. It is one of the hottest planets in our solar system due to its proximity to the sun.
5. The surface of Mercury is covered with craters from asteroid impacts.
6. It has a day that lasts longer than its year, taking 59 Earth days to complete one rotation on its axis and 88 Earth days to orbit around the sun.
7. Despite being small in size, it has a high density similar to Earth’s.
8. The temperature on Mercury can reach extreme highs during daytime and drop drastically at night due to its lack of an atmosphere for heat retention.
9. Scientists have discovered water ice near Mercury’s poles inside permanently shadowed craters where sunlight never reaches them directly.
10. Spacecraft like NASA’s Messenger mission and ESA’s BepiColombo have provided valuable insights into this mysterious planet.

Venus Facts

1. Venus is the second planet from the Sun.
2. It is often referred to as Earth’s sister planet due to its similar size and composition.
3. Venus has a very thick atmosphere composed mainly of carbon dioxide.
4. The surface temperature on Venus can reach up to 900 degrees Fahrenheit (475 degrees Celsius), making it hotter than Mercury despite being farther from the sun.
5. It has no moons or rings like some other planets in our solar system.
6. Venus rotates on its axis in the opposite direction compared to most other planets, resulting in retrograde rotation.
7. A day on Venus is longer than its year; it takes about 243 Earth days for Venus to complete one rotation but only around 225 Earth days to orbit the sun once.
8. The atmospheric pressure on Venus is more than 90 times higher than that of Earth, which makes it inhospitable for human life as we know it.
9. Despite its cloudy appearance, radar mapping has revealed that there are over a thousand volcanoes on the surface of Venus, although they appear to be currently inactive.
10. Due to its brightness and proximity to Earth, Venus is often called the evening star or the morning star.

Earth Facts

1. Earth is the only planet known in our solar system that supports life.
2. It takes approximately 365.25 days for Earth to complete one orbit around the sun, resulting in a leap year every four years.
3. The highest point on Earth is Mount Everest, towering at 8,848 meters (29,029 feet) above sea level.
4. Our planet has an impressive diversity of ecosystems, from lush rainforests to vast deserts and everything in between.
5. Earth’s atmosphere protects us by filtering harmful ultraviolet radiation from the sun and providing oxygen for us to breathe.
6. The deepest part of our oceans is called the Mariana Trench and reaches a staggering depth of 10,994 meters (36,070 feet).
7. Earth’s magnetic field helps protect us from charged particles emitted by the sun through its interaction with our atmosphere.
8. Our home planet has a fascinating geological history with evidence of volcanic activity, tectonic plate movement, and ancient civilizations buried beneath its surface.
9. Approximately 71% of Earth’s surface is covered by water found in oceans, seas, lakes, rivers, and glaciers – making it often referred to as the Blue Planet.
10. Earth experiences four distinct seasons due to its axial tilt as it orbits around the sun.

Mars Facts

1. Mars is the fourth planet from the sun.
2. It is often called the Red Planet due to its reddish appearance.
3. Mars has a thin atmosphere composed mainly of carbon dioxide.
4. The surface of Mars is covered in iron oxide, giving it a rusty color.
5. Olympus Mons, on Mars, is the largest volcano in our solar system.
6. Valles Marineris, a canyon system on Mars, is one of the largest in our solar system as well.
7. Scientists have found evidence that liquid water once existed on Mars’ surface.
8. A Martian day or sol is slightly longer than an Earth day – about 24 hours and 37 minutes long.
9. The gravity on Mars is about 38% of Earth’s gravity, which means you would weigh less there!
10. Mars has two small moons named Phobos and Deimos.

Jupiter Facts

1. Jupiter is the largest planet in our solar system.
2. It has a whopping 79 known moons, with four of them being large and well-known: Io, Europa, Ganymede, and Callisto.
3. The famous Great Red Spot on Jupiter is actually a massive storm that has been raging for over 300 years.
4. Jupiter’s atmosphere is made up mostly of hydrogen and helium gases.
5. The planet spins incredibly fast, completing one rotation in just under 10 hours.
6. Jupiter experiences intense auroras near its poles due to interactions with its strong magnetic field.
7. Unlike Earth, which takes about 365 days to orbit the sun, it only takes Jupiter around 12 Earth years to complete one trip around the sun.
8. If you were standing on Jupiter’s surface (if it had one), you would feel an extremely powerful gravitational force – more than two times stronger than what we experience on Earth.
9. Scientists believe that beneath its thick clouds lies a core made primarily of rock and metal.
10. Jupiter plays an important role in shaping our solar system by acting as a cosmic vacuum cleaner, attracting or deflecting asteroids and comets away from inner planets like Earth.

Saturn Facts

1. Saturn is the sixth planet from the Sun.
2. It is known for its iconic and prominent ring system.
3. With a diameter of about 74,900 miles, it is the second largest planet in our solar system.
4. Saturn has at least 82 moons orbiting around it.
5. Its atmosphere is primarily composed of hydrogen and helium gas.
6. The average temperature on Saturn can reach as low as -300 degrees Fahrenheit (-184 degrees Celsius).
7. A day on Saturn lasts approximately 10 hours and 33 minutes.
8. This gas giant’s gravity is strong enough to compress its core into a solid state despite being mostly made up of gas.
9. The Cassini spacecraft mission provided valuable insights into Saturn’s atmosphere, rings, and moons during its exploration from 2004 to 2017.
10. In Roman mythology, Saturn was named after the god of agriculture and harvest.

Uranus Facts

1. Uranus is the seventh planet from the sun.
2. It was discovered in 1781 by astronomer William Herschel.
3. The planet’s unique feature is its sideways rotation, making it appear to roll on its side.
4. Uranus has a striking blue color due to the presence of methane gas in its atmosphere.
5. It takes Uranus approximately 84 Earth years to complete one orbit around the sun.
6. The planet experiences extreme seasons that last for over 20 years each, due to its tilted axis of rotation.
7. Uranus has a system of faint rings made up of dust and small rocks surrounding it.
8. The largest moon of Uranus is named Miranda and features deep canyons and cliffs on its surface.
9. Unlike other planets, Uranus does not have a solid surface but rather consists mainly of gases like hydrogen and helium with traces of methane and ammonia.
10. Uranus has been visited only once by a spacecraft called Voyager 2 in 1986, providing valuable data about the planet’s composition and atmosphere.

Neptune Facts

1. Neptune is the eighth planet from the sun in our solar system.
2. It is classified as an ice giant, similar to its neighbor Uranus.
3. Neptune has a beautiful blue color due to methane gas in its atmosphere.
4. The planet was named after the Roman god of the sea because of its deep blue hue.
5. One day on Neptune lasts about 16 hours and 6 minutes, making it one of the shortest days among all planets.
6. Its average temperature is around -353 degrees Fahrenheit (-214 degrees Celsius), making it one of the coldest places in our solar system.
7. Neptune has a series of faint rings made up mostly of dust particles and rocky debris.
8. The Great Dark Spot, a large storm-like feature discovered by Voyager 2 spacecraft in 1989, disappeared when observed again later by Hubble Space Telescope in 1994-95.
9. Triton, Neptune’s largest moon, orbits backwards or retrograde compared to most other moons in our solar system which orbit their respective planets forward or prograde.
10. Neptune’s magnetic field is approximately 27 times stronger than Earth’s magnetic field.

Pluto Facts

1. Pluto is the farthest planet from the sun in our solar system.
2. It was discovered in 1930 by astronomer Clyde Tombaugh.
3. Pluto is smaller than Earth’s moon, making it one of the smallest planets.
4. Its average temperature is around -375 degrees Fahrenheit (-225 degrees Celsius).
5. Pluto has a thin atmosphere primarily composed of nitrogen with traces of methane and carbon monoxide.
6. The surface of Pluto contains mountains, plains, and icy regions known as Sputnik Planitia.
7. It takes approximately 248 years for Pluto to complete one orbit around the sun.
8. In 2006, due to its size and characteristics, Pluto was reclassified as a dwarf planet.
9. Four moons orbit around Pluto: Charon, Styx, Nix, and Hydra.
10. NASA’s New Horizons spacecraft flew past Pluto in July 2015 and provided us with detailed images and data about this distant world.

Solar System Fact Cards

Teach your kids about the solar system using our colorful planet fact cards full of fun facts about all-things space!

Solar System Facts

You’ve learned quite a bit about the individual planets found in our solar system, but here’s some interesting facts about the solar system.

1. The solar system is home to countless asteroids, which are rocky objects that orbit the sun.
2. Comets, consisting of ice and dust, also exist in the solar system and have long tails when they approach the sun.
3. The Kuiper Belt is a region beyond Neptune where icy bodies called Kuiper Belt Objects reside.
4. Dwarf planets like Pluto and Eris have unique characteristics but do not meet all criteria to be classified as full-fledged planets.
5. Many meteoroids travel through space before entering Earth’s atmosphere as meteors and burning up upon entry.
6. Some moons within the solar system exhibit interesting geological activity, such as volcanic eruptions or subsurface oceans.
7. Solar flares are powerful bursts of energy from the sun that can cause disruptions on Earth’s magnetic field and communication systems.
8. The Oort Cloud is a hypothetical region far beyond Pluto that may contain trillions of comets surrounding our solar system.
9. Interplanetary space contains tiny particles known as cosmic dust grains originating from various sources throughout the universe.
10. The heliosphere acts as a protective bubble around our solar system created by the influence of the sun’s magnetic field on interstellar gas.
11. Ceres is the largest object within the asteroid belt between Mars and Jupiter, accounting for about one-third of its total mass.
12. Eris, discovered in 2005, is slightly larger than Pluto and played a role in redefining what constitutes a planet.
13. Makemake is another dwarf planet residing beyond Neptune with a reddish surface likely caused by methane ice.

What’s the smallest planet?

The smallest planet in our solar system is Mercury.

What’s the biggest planet?

The biggest planet in our solar system is Jupiter.

What’s the hottest planet?

The hottest planet in our solar system is Venus.

What’s the coldest planet?

The coldest planet in our solar system is Neptune.

Facts About the Sun

1. The sun is a star located at the center of our solar system.
2. It provides heat and light to sustain life on Earth.
3. The sun’s diameter is about 109 times that of Earth.
4. Its surface temperature reaches up to 5,500 degrees Celsius (9,932 degrees Fahrenheit).
5. Sunspots are temporary dark spots on the sun’s surface caused by magnetic activity.
6. Solar flares are intense bursts of radiation emitted from the sun’s surface.
7. The core of the sun produces energy through nuclear fusion reactions.
8. The mass of the sun accounts for more than 99% of all matter in our solar system.
9. It takes approximately 8 minutes and 20 seconds for sunlight to reach Earth.
10. The outermost layer of the sun’s atmosphere is called the corona, which can be seen during a total solar eclipse.
11. Solar winds are streams of charged particles ejected from the sun into space.
12. Auroras occur when these charged particles interact with Earth’s magnetic field near its poles.
13. The gravitational pull exerted by the Sun keeps all planets in orbit around it.
14. Earth experiences seasons due to its axial tilt relative to the Sun.
15. The Sun rotates on its axis once every 27 days at its equator and slower at higher latitudes.
16. About one million Earths could fit inside the volume occupied by the Sun

Facts About the Moon

1. The moon is Earth’s only natural satellite, orbiting around our planet.
2. It has a diameter of about one-quarter that of the Earth.
3. The moon takes approximately 27 days to complete one orbit around the Earth.
4. Its surface is covered in craters formed by meteor impacts over many years.
5. The Moon lacks an atmosphere and therefore does not have weather or air pressure like on Earth.
6. Lunar gravity is about one-sixth of Earth’s gravity, making objects weigh less on the moon compared to on our planet.
7. Apollo missions brought humans to the moon for the first time between 1969 and 1972.
8. There are dark patches called maria (Latin for seas) on the lunar surface that were once thought to be filled with water but are actually solidified lava flows from ancient volcanic activity.
9. The same side of the moon always faces towards Earth due to its synchronous rotation – this means we never see its far side directly from our planet!
10. The phases of the moon change throughout each month as it orbits around us, going through new moon, crescent, half-moon (first quarter and third quarter), gibbous, and full moon stages.

Dwarf Planets Facts

1. Dwarf planets are celestial bodies that orbit the sun and have enough mass to form a sphere shape.
2. Pluto was considered the ninth planet in our solar system until it was reclassified as a dwarf planet in 2006.
3. There are currently five recognized dwarf planets: Pluto, Eris, Haumea, Makemake, and Ceres.
4. The largest known dwarf planet is Eris, which is even more massive than Pluto.
5. Many dwarf planets reside in the Kuiper Belt, a region beyond Neptune’s orbit filled with icy objects.
6. Dwarf planets can have moons of their own; for example, Pluto has five known moons.
7. Unlike regular planets that have cleared their orbits of other debris, dwarf planets share their orbital space with other objects.
8. One of the most intriguing features of some dwarf planets is their odd shapes caused by rotation or collisions with other celestial bodies.
9. Some scientists believe there may be hundreds or even thousands of undiscovered dwarf planets in our solar system waiting to be found.
10. Dwarf planets provide valuable insights into planetary formation and help us understand more about the outer reaches of our solar system.

Facts About Asteroids

1. Asteroids are rocky objects that orbit the sun, mostly found in the asteroid belt between Mars and Jupiter.
2. They vary in size, ranging from small boulders to large bodies measuring hundreds of kilometers across.
3. Some asteroids have moons of their own, which orbit around them just like our moon orbits Earth.
4. Asteroids can be made up of different materials, such as metals or rocks mixed with ice.
5. Scientists believe that many asteroids are remnants from the early formation of our solar system.
6. Occasionally, asteroids collide with each other or get knocked off course by gravitational interactions with planets.
7. Near-Earth asteroids (NEAs) come close to our planet’s orbit and pose a potential risk for impact on Earth.
8. NASA has sent spacecraft missions to study asteroids up close, including sample return missions like OSIRIS-REx and Hayabusa2.
9. The largest known asteroid is called Ceres and it is so big that it is considered a dwarf planet too!
10. In rare cases, when an asteroid enters Earth’s atmosphere and survives the intense heat friction, it becomes a meteorite upon reaching the ground.

Comets Facts

1. Comets are cosmic wanderers made up of ice, dust, and various organic compounds.
2. They originate from the outer regions of our solar system in a region called the Oort Cloud or Kuiper Belt.
3. The nucleus of a comet is solid and can range in size from just a few meters to tens of kilometers.
4. As comets approach the sun, they heat up and release gas and dust into space, forming a glowing coma around them.
5. The tail of a comet is created when solar radiation pushes these released particles away from the sun.
6. Some famous comets include Halley’s Comet, Hale-Bopp Comet, and Comet Shoemaker-Levy 9 which collided with Jupiter in 1994.
7. Comets have been observed for thousands of years by civilizations all over the world.
8. Scientists study comets to learn more about the early solar system as they contain materials that have remained relatively unchanged since their formation.
9. A spacecraft named Rosetta successfully landed on a comet named 67P/Churyumov-Gerasimenko in 2014 – marking humanity’s first-ever soft landing on such an object.
10. Cometary impacts may have played an important role in delivering water and other volatile substances to Earth during its early history.

Facts About Meteors

1. Meteors, also known as shooting stars, are small celestial bodies that enter Earth’s atmosphere.
2. Most meteors are fragments of asteroids or comets.
3. They can reach speeds of up to 70 kilometers per second (43 miles per second) as they travel through the atmosphere.
4. The bright streaks we see in the sky when a meteor burns up are caused by friction with the air.
5. Meteors can vary in size from tiny specks of dust to larger objects several meters in diameter.
6. When a meteor survives its journey through the atmosphere and lands on Earth’s surface, it is called a meteorite.
7. Meteor showers occur when Earth passes through streams of debris left behind by comets or asteroids.
8. The Perseids and Geminids are two well-known annual meteor showers visible from many parts of the world.
9. Some meteors produce fireballs, which are exceptionally bright and often accompanied by loud sounds or sonic booms.
10. Meteors have been observed throughout history and have inspired myths, legends, and scientific study.

Fun Ways to Remember the Order of the Planets

• Acronyms: Create a catchy acronym using the first letter of each planet’s name. For example, My Very Eager Mother Just Served Us Noodles represents Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune.
• Mnemonic Devices: Make up a sentence where each word starts with the same letter as a planet’s name in order. For instance, Many Vampires Eat Marshmallows Jamming Screaming Ukuleles Noisily.
• Songs: Sing or create a song that lists the planets in their correct order. You can find many educational songs online that make learning fun and memorable.
• Memory Games: Play memory games using cards or digital applications specifically designed for learning planetary sequences.
• Visual Aids: Use posters or charts displaying vivid images of all the planets placed correctly according to their position from our star.