Is life on Mars really worth it? The European Space Agency thinks we will soon be able to live in space. But scientists are divided on whether this is a good idea — or even possible.
Humans to live beyond Earth ‘by 2040’
A land far, far away: Mars is approximately 140 million miles away from Earth — Nasa estimates that any astronaut going to Mars would be away for at least three years. Glossary
Mars - The fourth planet from the Sun and the second-smallest planet in the Solar System.
Galaxy - A system of millions or billions of stars, gas and dust, held together by gravitational attraction.
Nasa - The National Aeronautics and Space Administration, responsible for the US space programme.
Replica - An exact copy or model of something.
Polluting - To make air, water or earth dirty and harmful.
Extreme - Very great, or beyond what is expected.