Imagine that you鈥檙e just about to take your first spacewalk. As you go through the hatch, the International Space Station (ISS) is moving at around 17,000 miles per hour. The earth鈥檚 surface is 250 miles below you.
You鈥檙e sweating, and your heart is hammering loudly. The voices of your crew crackle on the radio. But outside of your spacesuit, everything鈥檚 quiet. There鈥檚 no noise at all.
So what鈥檚 the story here traveller? Light travels across space, but what about sound?
The story of starlight
Although sound waves can鈥檛 travel in space, light waves can. That鈥檚 why everything we know about the Universe comes from light.
Light travels at an amazing 299,792 kilometers per second. It can go seven-and-a-half times around the world in one second. But 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鈥檚 age, surface temperature and the direction it鈥檚 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鈥檚 greatest mysteries.
Explore the gallery below to find out about some of the most beautiful and extraordinary images of our Universe.
Space gallery
1 of 8
Your eyes in the sky
Your eyes aren't powerful enough to see all the secrets of space. That鈥檚 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鈥檚 atmosphere disturbs and blurs our pictures of the Universe. But by putting telescopes into space, you can solve these problems instantly.
Satellites and probes offer similar benefits. 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 it鈥檚 now over 12 billion miles away.
No doubt you鈥檒l see some major space technology breakthroughs during your lifetime. Who knows what we鈥檒l uncover?
Bitesize Primary games. game
Play fun and educational primary games in science, maths, English, history, geography, art, computing and modern languages.
More on Earth and space
Find out more by working through a topic
- count12 of 14
- count13 of 14
- count14 of 14
- count1 of 14