THE UNIVERSE. The universe.jpgTHE MILKY WAY.

Gap-fill exercise (by Juan Luis Serrano Pedrosa).

Fill in all the gaps, then press "Check" to check your answers. Use the "Hint" button to get a free letter if an answer is giving you trouble. You can also click on the "[?]" button to get a clue. Note that you will lose points if you ask for hints or clues!

USE THESE WORDS.

200
planets
14
stars
Milky Way
telescope
100
stars
Big Ben
astronomers

THE UNIVERSE.

The Universe is everything that exists. It consists of celestial bodies such as galaxies, planetary systems, stars, , satellites and asteroids.
Gases and dust also form part of the Universe.
Most astronomers believe the Universe began with a huge explosion called the «», about billion years ago.

Our galaxy: the Milky Way.

A galaxy is a group of and planetary systems. There are many galaxies in the Universe.
The is shaped like a huge spiral. It rotates once every million years. It contains about billion stars, together with dust and gas. It is immense.
The solar system is one of the many planetary systems in the Milky Way. In our galaxy there are many other , planets and satellites.
The scientists that study the Universe are called . They use to observe and study celestial bodies.