What Is Space Made Of? It’s Complicated

Space is one of the universe’s great unknowns.

There’s so much that we don’t know about space, and much of its vastness remains a mystery to us.

With trillions of stars, planets, and galaxies in the universe, it’s hard to comprehend what exactly space is made of.

What things make up our universe? What matter, if any, fills the vastness with space? As it turns out, the answer is kind of complicated.

If you’ve ever wondered what space is made out of, then you’ve come to the right place!

In this article, we’ll take a look at what exactly makes up the space beyond our atmosphere, from the many astral bodies within the expanse of our universe to the types of matter that space itself is made out of.

Ready? Then let’s dive in!

What Is Space, Exactly?

Our universe is occupied by trillions of different planets, stars, galaxies, and other astral bodies.

But despite the incredible amount and size of these bodies, they are insignificant compared to the vast expanse of space in between them.

It’s hard to grasp just how big space is.

The observable universe is around 28 billion light-years across; this might not mean much on its own, so here’s a quick breakdown.

A light-year is the distance that light can travel in a vacuum in a year.

Given that light in a vacuum travels around 300,000 km every single second, the full size of the universe is impossible to really comprehend.

The universe is also constantly expanding, which makes it even harder to get a handle on.

While there are countless planets, stars, asteroids, moons, and other similar things floating in space, there are often thousands or millions of kilometers between them.

This empty void is what makes up the vast majority of the universe, and is what we refer to when we think of space.

However, is space really empty, or is there matter within our universe that we can’t see or understand?

To understand that, we’ll need to take a look at the types of matter that make up the universe.

The Types Of Matter In Space

There are three main types of matter in space: baryonic matter, dark energy, and dark matter.

These make up different parts of the matter in the universe, but are dramatically different in their makeup and quantity.

Here’s a breakdown of what makes each type of matter, and what their place is in space.

Baryonic Matter

Baryonic matter is a type of dark matter that includes any matter made of baryons.

This means that anything composed of protons, neutrons, and electrons is classed as baryonic matter.

While this includes things like elements, chemicals, and most physical matter, baryonic matter actually only makes up a tiny proportion of the matter in the universe.

Baryonic matter is less than 5% of the matter in the observable universe, with the rest being comprised of dark matter and dark energy (which we’ll cover next).

Interestingly, black holes are considered to be baryonic matter.

While black holes are completely different from other baryonic objects such as planets and stars, they are also classed as baryonic matter due to them being made out of incredibly dense neutrons.

Dark Energy

Dark energy is another form of matter found in space and accounts for around 70% of the matter in the universe.

There’s a lot we don’t understand about dark energy, but we do know about several of its qualities.

Dark energy isn’t very dense, resulting in it not interacting with any forces other than gravity.

Dark energy acts in opposition to gravity, and as a result, matter is repulsed by it.

It also has an extremely large negative pressure, meaning that it pushes everything away from itself.

Because of this negative pressure and opposition to gravity, dark energy is the force behind the universe’s expansion.

In fact, dark energy has such a strong influence that the expansion of the universe is constantly increasing in speed, despite the incredible size of space it is enlarging.

Dark Matter

Dark matter makes up the remaining 25% of matter. Dark matter comprises particles that we can’t observe.

These particles don’t absorb, emit, or reflect light, and as a result, can’t be seen.

They also don’t emit any electromagnetic radiation, which makes dark matter difficult to detect at all.

Most of our understanding and observation of dark matter comes from seeing it interact with other objects that we can see; in essence, we can’t see what dark matter is, but we can see how it behaves by watching other, visible matter.

It’s important to note that while dark matter doesn’t emit any light, it does have mass – in fact, dark matter makes up for five times the mass of baryonic matter (aka the matter that we can observe and interact with).

Because of this, it interacts with other forms of matter through gravity.

As a result, dark matter is responsible for holding galaxies together, keeping them stable, and preventing them from flying apart.

What Elements Are There In Space?

So now we know a bit more about the types of matter in space, what elements are they made out of?

Chemical elements make up all the matter that we can observe, from the solids, liquids, and gases on earth to the baryonic matter in space.

But as we’ve covered already, baryonic matter makes up just 5% of the matter in space; dark matter and dark energy are both non-baryonic, and as such aren’t made up of chemical elements like the matter we can observe.

So with so little baryonic matter in the universe, what chemicals is it composed of?

While space is a vacuum, it’s not actually completely empty.

The particles in space are extremely far apart, which makes them pretty much impossible to observe.

However, we’re able to measure these clouds of gaseous particles using specialized telescopes and sensors, which tell us which elements fill the void with space.

Hydrogen is by far the most abundant element in space, making up a massive 73% of all atoms.

Hydrogen is the most basic element, with one proton, one electron, and no neutron (the only element without one).

This makes hydrogen a great building block for other forms of matter.

The other 27% of atoms are made up of various other elements; the next most common is helium, which makes up 25% of leftover matter in the universe.

The remaining 2% is a collection of several trace elements that aren’t present in significant quantities.

These include small amounts of oxygen, carbon, and iron.

It might seem odd that hydrogen makes up the vast majority of baryonic matter in space, considering that on Earth there are far more elements present in much higher quantities.

However, the abundance of hydrogen is due to its relative simplicity.

With just one proton and one electron, hydrogen is a simple element that can combine with itself or other elements to create strong molecules that can be used as building blocks for other matter.

Final Thoughts

So now you know a bit more about what space is made of, from the different types of matter that occupy the observable universe to the various elements that fill the vacuum with space.

There is so much that we don’t yet know or understand about outer space, but we discover new and fascinating things every single day.

Hopefully, someday in the near future, we’ll be able to unravel some mysteries in the universe, including just what exactly space is made of.

With only 5% of the matter in space being observable, there’s a lot that we still need to discover about dark matter and dark energy.

For now, though, we will continue to learn more about space and the incredible expanse beyond our atmosphere!