Space

If you go beyond our atmosphere, you will be in outer space. Outer space is a dangerous place, as there is no oxygen. In space, there is no gravity, so everything floats.

We use to get to space using space shuttles, which use huge thrusters to get themselves off the ground. We also send satellites up to space. Some of them orbit earth, and those satellites let us make phone calls, emails, and lots of other stuff. Other satellites are sent far into space to study planets and asteroids.

If astronauts want to walk on a planet, they have to wear a special suit. The suit includes a supply of oxygen and a unit called the “manned manoeuvring unit” (or MMU). The MMU has a camera attached to it so that the astronaut can take pictures while in space. It takes about an hour to put on the suit.

But even though going into space is exciting, it can still be dangerous. Many accidents have happened, including the explosion of the space shuttle Columbia. The shuttle had spent 16 days in space, but when it re-entered  earth’s atmosphere, it exploded, killing everyone on board.

Space has lots of galaxies. Galaxies can be identified by their shape. Spiral galaxies are shaped like a disc and have long spiralling arms, elliptical galaxies are shaped like a sphere, and galaxies that have no fixed shape are called irregular galaxies. The galaxy we live in is a spiral galaxy called the Milky Way.

The unit of measurement we use in space is called a light-year. A light-year is the distance light travels in a year. 1 light-year is 9,460 billion km (5,868 billion miles). The size of our solar system is more than 1 light-year. The size of the Milky Way, the galaxy we live in, is 100,000 light-years.

Space is a fascinating and dangerous place. Even though we know quite a lot about it, there are still thousands of unanswered riddles to solve about space.