Text size
Line height
Text spacing
Do waves hold the secrets of space?
Completion requirements
Do waves hold the secrets of space?
Last modified: Monday, 6 April 2026, 2:35 PM
Do waves hold the secrets of space?
What is a wave?
When we think of a wave, we might think of someone moving their hand from side to side to say 'hello' or 'goodbye'.
We might think of the crashing waves in the Earth's oceans.
In science, a wave is the transfer of energy from one place to another. You may have heard of light waves or sound waves before.
Some telescopes, like the James Webb telescope, can detect waves in space from things like black holes and supernovas
What waves are there in every day life?
There are lots of waves all around us in everyday life.
There are waves in our seas and oceans. You can drop a rock into a pond and see waves form in the water.
Sound is a type of wave that moves through matter and then vibrates our eardrums so that we can hear.
Light is a special kind of wave that is made up of photons.
We even use waves (microwaves) to cook our food really fast.
We can see waves in our seas and oceans
Waves in space
In space, we can find lots of different types of waves.
These waves carry information about space objects, like how far away they are, how fast they're moving and what they're made of.
By studying these waves, scientists and astronomers are uncovering mysteries about the Universe.
So, what kind of waves do we find in space?
Light waves
Everything we know about the Universe comes from light.
Light from stars and galaxies travel through space in waves.
Scientists use special telescopes to capture these light waves and learn about things that are far away.
A star's light contains information about the star's age, its surface temperature and the direction it's heading.
Radio waves
Radio waves are like messages from faraway objects in space.
Astronomers use large radio telescopes to 'listen' to space.
These waves can tell us about things such as black holes, pulsars and even signals from other galaxies.
Gravitational waves
Gravitational waves are ripples in space itself. They happen when something really massive moves, such as when two black holes crash into each other.
These waves help scientists understand super big events in space that we can't see with light.
Sound waves need a medium to travel through. This is because they vibrate the particles to pass on the energy.
In space, there are virtually no particles to vibrate so sound waves can't travel in space.
However, scientists can turn the waves we receive from space into sounds that we can hear such as star's heartbeat or the rumble of a black hole.
Tim Peake on sound in space
Black holes are giant concentrations of matter, their gravitational pull is so strong that not even light can escape
Fascinating facts
- Sound waves can travel through solids, liquids and gases.
- The speed of light in air is very close to 300,000,000 m/s, which is nearly a million times faster than the speed of sound.
- Light waves travel in a straight line.
- Radio waves have the longest wavelengths in the electromagnetic spectrum.
- Gravitational waves were first predicted in 1893 by the English scientist Oliver Heaviside. In1916 physicist Albert Einstein demonstrated the existence of gravitational waves using his general theory of relativity.
- Gravitational waves are caused by violent or energetic processes in our Universe such as explosions, stars collapsing and black holes.
- Black holes absorb every kind of wave including light waves. If you went near one, it would be impossible to escape.
- The Hubble Space Telescope, which launched in 1990, has been used to see galaxies 13.4 billion light-years away
The story of starlight
Although sound waves can’t travel in space, light waves can. That’s why everything we know about the Universe comes from light.
Light travels at an amazing 186, 282 miles per second. It can go seven-and-a-half times around the world in one second. Even at this speed, it takes light over 100,000 years to travel across our galaxy alone. The entire Universe is so big that many stars are already dead by the time their light reaches us.
Scientists have discovered that each star has its own unique light reading. Even though we could never visit them, we can use their light to study them. Written in the starlight is information about a star’s age, surface temperature and the direction it’s heading.
Astronomers have used light to reveal even more about space. They have discovered alien worlds, the age of our Universe and even the forces at play around a black hole. In short, light is helping us unlock some of space’s greatest mysteries.
It might look nearby, but the Sun is actually over 90 million miles away. It still takes light about eight minutes to travel from the Sun to Earth
Our Universe
Explore the gallery below to find out about some of the most beautiful and extraordinary images of our Universe.
This image shows the Earth rising above the surface of the Moon. It was taken by astronauts on-board the Apollo 17 spacecraft (the last piloted mission to the Moon) as they orbited the lunar surface in 1972.
These pictures were taken by the Suomi NPP satellite and shows what Earth looks like from outer space. The satellite took hundreds of different photographs to give a complete map of our planet.
Robotic rovers and landers have been sent to explore some of the planets and moons in our Solar System. In 2014, NASA’s Curiosity rover sent back this ‘selfie’ from the surface of Mars.
This image of Saturn’s rings was taken by NASA’s Cassini probe in 2013. That tiny pale blue dot in the distance is the Earth viewed from 900 million miles away. Before the picture was taken, NASA asked people to look up and smile for the camera.
For years the surface of Pluto was a mystery, but in July 2015 the New Horizons probe beamed back images in brilliant detail. It showed a beautiful, icy world with a great heart-shaped plain, mountains and possibly glaciers of frozen nitrogen.
Since 1990 the Hubble Space Telescope has given scientists a glimpse into the furthest reaches of our Universe. This image of the Orion Nebula is just one of them. Nebulae are vast clouds of dust and gas where stars form.
Did you know?
Satellites and probes offer similar benefits to telescopes.
Probes are unmanned spacecraft on a one-way ticket into space. They pick up scientific data about our Universe and beam it back to Earth.
Some probes orbit and land on different planets. Others head out into space. The probe Voyager 1 set off on its journey in 1977 and is now over 15.6 billion miles away!
The Voyager 1 probe visited and studied Saturn in 1980
Our eyes in the sky
Your eyes aren't powerful enough to see all the secrets of space. That’s why scientists use telescopes, satellites and probes to observe the Universe in greater detail. These instruments can also pick up light that is undetectable to our eyes.
Studying light on Earth has a few problems. The Earth’s atmosphere disturbs and blurs our pictures of the Universe. By putting telescopes into space, these problems can be solved instantly.
The James Webb Space Telescope launched on the 25th December, 2021 and is the largest telescope in space. Unlike the Hubble Space Telescope, it orbits the Sun (roughly 1 million miles away) not the Earth.
It can see further into the Universe than ever before, viewing supernovas, black holes and galaxies at the edge of the known Universe. It will help astronomers learn about the history of our Universe.
