Think you know space? Eight celestial myths debunked

That’s where our space experts can help. Our planetary scientist Dr Ashley King is here to set the record straight on some popular myths about space.

1. Is there gravity in space?

Have you ever seen videos of astronauts and objects floating around inside spacecraft, seemingly weightless? There’s a common assumption that this is because there’s no gravity in space. However, this isn’t the case.

Gravity is present everywhere – even in space. For example, it’s the force that keeps the Moon orbiting Earth and Earth orbiting the Sun.

“Gravity is a really weak force, but it does very powerful things. Everything has some sort of gravitational attraction,” explains Ashley.

Gravity is how spacecraft, such as the International Space Station (ISS) and satellites, stay in orbit around Earth. These objects, as well as the astronauts and things aboard the ISS, for example, may appear to be floating, but they’re actually in a state of free fall as they’re pulled back to Earth by its gravity. When there’s no air resistance – such as in the vacuum of space – all objects free fall at the same speed, no matter their weight.

Things orbiting Earth don’t crash into us because instead of falling they’re going in a horizontal direction. The closer the object is to Earth, the faster it needs to travel to counteract gravity’s pull. For example, the ISS travels at around 28,000 kilometres per hour, allowing it to continuously fall around the planet rather than crashing into it.

2. How crowded is the asteroid belt?

The asteroid belt is a region located between the orbits of Mars and Jupiter. It’s filled with millions of rocky objects called asteroids.

The asteroids here range in size from small rocks that are just a few metres across to much larger bodies. The biggest is Ceres – a dwarf planet with a diameter of roughly 900 kilometres.

If you’ve seen movies such as Star Wars: The Empire Strikes Back, you might think that the rocks in places like the asteroid belt are packed closely together. But the reality is much different.

“They’re not close together at all. It’s an enormous area and the distance between the rocks is huge. In fact, the average distance between asteroids in the belt is nearly one million kilometres, which is further than travelling to the Moon and back,” says Ashley.

“When they send space missions to the outer solar system, they don’t worry too much about going through the asteroid belt because the chances of hitting something are so small.”

3. What is a shooting star?

If you look up at the stars at night, you might be lucky enough to see a bright streak shoot across the sky. Many of us know these as shooting stars, but this name is quite deceiving.

“Shooting stars are meteors. They’re bits of dust and rock coming from comets or asteroids that have entered our atmosphere. They travel really fast in space but, as they hit the dense atmosphere, they begin to slow down and heat up. This is what creates that bright streak that you can see in the sky,” explains Ashley.

“If you have a bigger rock that’s maybe a metre or several metres in size, you’ll get a much brighter streak in the sky, and we call that a fireball. It’s essentially a really bright shooting star. There’s a chance that some of that rock could land on Earth, which is when we call it a meteorite.”

When Earth travels through patches of rocky debris in space, we see high concentrations of meteors, often known as a meteor shower. Check out our guide to find out when and how to watch meteor showers.

4. Is there a dark side of the Moon?

Although the concept has cropped up in music – Pink Floyd’s iconic The Dark Side of the Moon album from 1973, for example – there is in fact, no light and dark side of the Moon.

“The Moon has a far side, which faces away from Earth. It’s often called the ‘dark side’, but it actually receives just as much sunlight as the near side, which is the side we can see from Earth,” Ashley says.

The Moon rotates on its axis at the same rate that it orbits Earth. This is called synchronous rotation or tidal locking and it’s the reason why we only ever see one side.

The far side of the Moon might not sound as exciting as the Moon having a dark side, but it’s still quite mysterious. For example, we only discovered in 2025 that the far side of the Moon is much drier than the side we can see.

“Because we can’t see the far side directly, we know much less about it, and there’s still lots of places on the Moon for us to explore.”

5. When will the Sun explode?

The Sun is a massive star and the idea that it could suddenly explode is quite scary, but it isn’t likely to happen.

“Stars are amazing. They’re like nuclear factories that generate energy by burning hydrogen into helium,” Ashley explains. “The Sun is quite a boring and really stable star, though. The speed at which stars burn their fuel depends on how big they were when they formed. A star the size of our Sun takes about 10 billion years to use up all of its fuel.”

“The Sun has used up about four and a half billion years of its fuel. It probably has another five billion years or so left in a pretty stable state. But even then, it won’t explode. It’s not big enough to do anything exciting like that. It will swell and then collapse, and that’ll be the end of it.”

Our Sun will shrink to become a white dwarf, but some stars do go out with a huge explosion known as a supernova. These stars are a lot bigger than the Sun and they burn their fuel very quickly – sometimes in only a few million years.

In our galaxy, the Milky Way, supernova events happen around every 50 years or so. However, no explosion would affect Earth as they’re so far away.

6. What colour is the Sun?

Have you ever drawn the Sun and coloured it in yellow? It might be difficult to believe, but the glowing light in our sky is actually white.

“The Sun is generating energy and heat. What we’re seeing is the light that’s coming off of the Sun. The reason it looks yellow is because of the way the light is going through our atmosphere,” says Ashley.

“The Sun emits light over the whole range of colours, however, the light that reaches our eyes has been scattered by Earth’s atmosphere. The atmosphere is better at scattering blue light than red light, which results in the Sun appearing yellow. Light scattering in the atmosphere is also the reason why the sky looks blue.”

The Sun is sometimes called a ‘ball of fire’. Although this sounds cinematic, the heat and light of the Sun are actually caused by the process of turning hydrogen into helium, which is called a thermonuclear reaction.

7. Where does the Moon go during the day?

We often associate the Moon with night-time, but it’s actually constantly hiding in plain sight.

“When you’re looking at the Moon, it isn’t generating any light itself. Stars, like the Sun, produce light,” Ashley explains. “What you’re seeing is the sunlight bouncing off the surface of the Moon. When it’s daytime, it’s often too bright to see the Moon, but it’s still there!”

“It’s the same with shooting stars. They’re happening all the time, but you don’t see them during the day it because the sky is just too bright.”

8. Is an asteroid going to hit Earth?

Although it’s technically true that an asteroid could collide with Earth, it’s not as likely as it’s sometimes made out to be.

“It’s likely that an asteroid will hit Earth at some point. It’s happened all the way through Earth’s history. A large asteroid impact has been linked to causing the dinosaurs to become extinct, for example,” Ashley explains.

When the solar system was forming billions of years ago, it was extremely unstable, and Earth was probably hit by a lot of asteroids. We can see a record of this turbulent time by looking at how many impact craters there are on the Moon. However, today things are much more stable.

“Even though the likelihood of something hitting us at some point is quite high, we’re now much better at detecting asteroids. In the past, we weren’t able to spot anything before it reached Earth. But these days we can detect the largest asteroids and we can work out their orbits long into the future.”

“The chances are that if anything was going to hit us that was big enough to cause something like an extinction type event, we would see it far enough in advance that we could think about how we might stop it,” reassures Ashley.

To protect Earth from possible asteroid strikes, several methods of defence have been explored. One was the Double Asteroid Redirection Test or DART. This was a NASA space mission in which a spacecraft purposely collided with the asteroid Dimorphos, successfully altering its orbit.

“Never say never, but even if Earth was going to be hit, chances are that we would probably be able to come up with some way of stopping it from happening.”

Are we alone in the universe?

We’ve not found signs of extraterrestrial life yet, but scientists are searching for clues.

Explore this big question at our exhibition, Space: Could Life Exist Beyond Earth? Open until 22 February 2026. Book your tickets.