Planets can be classified in many ways. In Unit 1 “Inner and Outer planets” we saw how they are classified according to their orbit relative to the orbit of the Earth. In this activity we will learn how they are classified according to their composition.

The four planets closest to the Sun (Mercury, Venus, Earth and Mars) are relatively small, warm, rocky, have few (if any) moons and no ring systems. We call them rocky or terrestrial planets, because of their resemblance to Earth.

The four planets farthest from our star (Jupiter, Saturn, Uranus and Neptune) are much larger, cooler and mainly consist of gas so we call them gas giants. Although from Earth we can only see Saturn’s rings, they all have many moons and ring systems.

Introduction

Download here the INTRODUCTION to this Didactic Unit.

Activities

In these activities you will be able to work with real images obtained with the Liverpool Telescope, just as professional astronomers do.

Activity Data

Concepts: Terrestrial and gas planets. Binoculars and telescopes: instruments for observation. Jupiter. Saturn.

Tools to learn to use: Distance measurement.

Estimated time: 3 hours.

Authors: Oswaldo González, Nayra Rodríguez, Alfred Rosenberg, Inés Bonet.

Materials for educators: Teacher’s guide.