Our solar system is an amazing collection of stellar bodies, planets, moons, rocky objects, and more. The mysterious of our existence can be traced not only here on Earth, but with the formation of other objects too. From the mighty Sun to the far off Kuiper Belt, there are numerous interesting solar system facts.
All About the Solar System and Interesting Solar System Facts
There are so many things to know about the solar system. It can’t all be fit into one page, but you’ll learn about some of the fascinating tidbits astronomers have learned over the past centuries.
There are 8 planets in the solar system.
Since the discovery of Eris and the Kuiper Built, astronomers have redefined what it means to be a planet. Up until this point, Pluto was thought to be the ninth planet in the solar system, but that’s now changed.
The age of the solar system is about 4.5 billion years.
After the formation of our star (the sun), conditions for a solar system were set. Rocky and icy objects were snagged by the sun’s gravity, eventually forming the planets, asteroid belt, and Kuiper Belt.
The hottest planet is actually Venus.
One might think Mercury – the closest planet to the sun – is the hottest planet. But, in fact, Venus holds that title. Venus’ thick atmosphere and dense, cloudy sky create a constant greenhouse effect, retaining a majority of the heat it absorbs.
The Solar System is large.
Another interesting solar system fact is that it extends well beyond Neptune and Pluto. After the discovery of Eris (another icy dwarf planet), astronomers learned of the Kuiper Belt and Oort cloud.
It’s the only place we know supporting life.
The universe is immense and filled with hundreds of billions of galaxies. However, as of now Earth is the only planet we know of able to support life. It’s likely there are more out there, but until discovery, we are unique as a world. (For some fun solar system products, take a look at these solar system projectors.)
Only two planets have no moons.
While over 150 moons currently exist in our solar system, two planets – Mercury and Venus – lack them. Moons are usually captured by a planet’s own gravity, though the planets proximity ot the Sun may cause too much gravitational interference.
Solar System Facts for Kids
We thought the Earth was the center of the universe.
Before astronomers discovered otherwise, humans once believed all things revolved around Earth (known as the “geocentric” model). Since the sun rose and descended, it seemed only natural to think this. We’re well aware, now, our planet and everything else in the system orbit the sun. By the way, if you want to get a closer look at the sun (safely), take a look at our favorite solar telescopes and solar filter sheets.
Jupiter, Saturn, Uranus and Neptune are all Gas Giants.
This interesting solar system fact means the four gas giants don’t have a solid surface. Their atmospheres are made mostly of hydrogen, ammonia, and helium. It’s possible they have a small, rocky core, though. However, if someone tried to “land” on one of them, there wouldn’t be a surface.
There are different objects in the solar system.
While planets are certainly fascinating, there are other objects too. Asteroids, meteoroids, icy-particles and icy-rocks are other ingredients to our cosmic neighborhood. The icy material astronomers observe out in the Oort Cloud may be the origin of water on Earth.
There are five dwarf planets.
Another interesting solar system fact relates to dwarf planets, objects which are technically planets but do not have their own unique orbit.
Currently, there are five known dwarf planets: the mentioned Eris and Pluto, along with Ceres, Makemake and Haumea. (For some fun sheets depicting celestial bodies, check out our favorite solar system sheets.)
Comets likely come from the Oort Cloud.
Though it’s a rare occurrence, comets appear in the Earth’s sky. They have long tails of icy material – but where do they come from? Astronomers believe comets originate from the Oort Cloud, a body of ice-rock objects surrounding the solar system. This is different from the Kuiper Belt, however.
Another name for comets is “dirty snowball”.
Asteroids were first discovered in 1801.
Asteroids were originally thought to be planets when they first were discovered by Giuseppe Piazzi. Asteroids are lumpy, rocky bodies caught by planetary gravity. Sometimes, asteroids are pulled into Jupiter, while others float into space. It’s better if Earth is never hit by an asteroid.
Origin of the Solar System Facts
While our solar neighborhood is indeed quite fascinating, it begs the question: how’d all that cool stuff get here, anyway? After all, massive worlds like Saturn didn’t appear overnight. And how about the sun? How did it get there?
While it’s impractical to go over the solar system’s creation in every minute detail, there is a basic map to give you and astronomers an idea of the solar system’s origin. However, it’s worth noting the true origins of our system are still debated among astronomers. Our current models are based on the most up-to-date theories. New knowledge and discoveries, though, can change our understanding of it.
There are some competing theories as to how it all came to be. We’ll list them here for your convenience.
The Capture Theory
The general idea behind this theory is that a fully formed sun ensnared the objects in our solar system, which, before were merely floating matter and rocks. The capture eventually lead to the development of environments on each planet.
The Gas Cloud Theory
Our sun captured stellar matter from nebula clouds which eventually formed the planets we know today. The elements from the stellar clouds reacting with the elements forming from the sun allowed for planetary creation
The Fission Theory
An outdated theory, some astronomers once believed the sun burst open, and from the eruption was the necessary material allowing for planetary creation. Based on modern discovery this is mostly an interesting solar system fact regarding the evolution of theories.
The Nebular Hypothesis
Today, this is the most commonly accepted theory about the solar system’s creation. It was believed the solar system started out as clouds of molecular gas and dust, until an event forced the material to condense together. What kind of event is still speculated on – some theorize it may have been a supernova or other astronomical occurrence.
As the matter pulled together, becoming more dense, said dense material formed stronger gravitational pulls. This lead to rotation, heat, and the eventual creation of denser matter. Some of this formed into the Sun, while the increase in heat generated matter like heavy metal elements – thus becoming the terrestrial (rocky) planets. Material farther out cooled down to become the gas giants. (You can even check out one of the coolest solar system sights on a stamp. Take a look at our favorite solar eclipse stamps here!)
The rest of the condensing matter formed into the sun over tens of millions of years. Once the star was created, it provided the additional elements and heat to creatable suitable living conditions here on Earth (although this too was a process requiring millions of years).
This theory was originally developed in the 16th century and is always evolving. The more astronomers learn, the more they can establish what happened (and what did not).
Fun Solar System Facts
Mars has a massive volcano.
Suggesting early volcanic activity, Mars has the largest volcano in the known solar system. It reaches 374 miles across known as Olympus Mons. While it’s no longer active, it suggests a diverse martian past astronomers hope to one day discover more about.
Venus is a world of storms.
Not only is Venus the hottest planet in the solar system, it’s a world of violent winds and never ending storms. Several Russian probes that landed there only survived a few minutes before they were destroyed.
Microbial life likely exists.
While intelligent life such as what we have on Earth isn’t in the system, microbial life is very possible. Microbes could exist in the deep, brine oceans of moons or planets.
Pluto has mountains.
Though the dwarf planet is small, it has a rough, varied surface. Enough that Pluto has several mountains, some reaching heights of up to 11,000 feet.
The Great Red Spot is getting smaller.
Jupiter is most known for its massive Red Spot, a storm on the gas giant which has raged for centuries. However, since the initial sightings from the 1600, astronomers have discovered the red mass is getting smaller. This could be because of changing planetary conditions, or the “storm” is dying down. However, no concrete answer explains why (yet).
Neptune produces more heat than it receives.
When we look at distant planetary objects, we expect them to be cold and icy. Neptune – while still technically an ice giant – produces more heat than it receives. There are no clear answers yet, but it may be due to reflective properties or internal systems astronomers haven’t seen.
Our world is fascinating, but so too are the stellar bodies near us. Each planet, asteroid, and moon all contain their own stories about their formation, how they came to be, and their own incredible environments. From lunar volcanoes to mysterious oceans of ethanol, our solar system is incredible and diverse, just like our home on Earth.
We hope you enjoyed reading some of these solar system facts, and encourage you to learn more about the system, astronomy, and the universe! (Looking for more cool solar system facts? Check out our guide to solar eclipses!)