This activity is part of teaching unit 1, Inner and Outer Planets. You can find the introduction and teaching guide here.

Mars is the closest outer planet to Earth. Both our planet and Mars revolve around the Sun, but they revolve at different velocities and take different times to complete their orbits. With this activity you can see how the apparent size of Mars (as we see it from Earth) changes as we move closer to or further away from the planet.

• Download the GUIDE of the activity: Unit 1 – Activity 2
• Download the images of MARS you are going to work with.
• Download this SPREADSHEET to write down your measurements.
• If you haven’t already done so, download the software (PeterSoft) to view and analyse the images.

Remember you can also obtain your own images of the planets in  “Go Observing” and make new measurements and investigations.