Practical exercise 1: DWARF PLANET

Exercise: How does a dwarf planet differ from a planet?

Answer: A dwarf planet is an object of the Solar System similar to a planet and has to fulfil the following criteria:

• orbits the Sun,

• has enough mass so that its gravitational forces form it into a nearly round shape (is in hydrostatic balance),

• during its development has not cleared the neighbourhood around its orbit in order to become dominant in the zone,

• is not a satellite.

The definition is the same as the definition of a planet except the third point.

Exercise: Name three dwarf planets and find out which part of the Solar System they are located in.

Answer: Ceres (main asteroid belt, between Mars and Jupiter), Pluto (behind Neptune’s trajectory), Haumea (behind Neptune’s trajectory), Makemake (behind Neptune’s trajectory), Eris (behind Neptune’s trajectory)