1. REVISION EXERCISES. THE UNIVERSE
1. Fill in the gaps:
a. ....................................... is a celestial body that emit ................... thanks to the
..................
b. All the ........................... share to main characteristics: They have clean
.......................... and a size that allow them to have a……………………………………
form.
c. The .................................. spin around the ........................ with eccentric
...............................and have components that vaporize when they are
.........................................................
d. The main components of the solar system are:
e.The planets of the solar system could be divided in two main groups,
......................................................... The Earth belongs to
the……………………………………..
2. Explain the main units of measure we can use in the Universe. ¿Where do we use
each of them?
3. How long will take us to arrive to a star that is 10 light-years from us if we are
travelling in a space-ship whose speed is 30.000 Km/h?

2. 5. Explain the differences among the stars at the picture:
6. Define: Solar System, galaxy satellite, nebula, star.

3. 7. Give a name to the pictures and explain what they represent: