Exoplanets Detective – Characterising exoplanetary systems

Brief description:

In this set of activities students will learn how scientists study exoplanets with telescopes, using the transit method.

Students will characterise exoplanets using model and real satellite light curves data from ESA’s satellite Cheops (CHaracterising ExOPlanet Satellite). They will practice data plotting and interpretation, and scaling of graphs in the context of exoplanet characterisation.

This activity is part of a series that includes “Exoplanets in Motion” where students build their own transit model and “Exoplanet in a Box” where students build a transit model inside a shoebox and calculate the size of an exoplanet.

Science, Physics, Mathematics, Astronomy

Learning Objectives:

  • Understanding what exoplanets are and how satellites investigate them.
  • Understanding how the transit method is used for the characterisation of exoplanets.
  • Enhancing experimental skills by observing and interpreting measured light curves.
  • Thinking mathematically and converting an abstract model to a real model.
  • Interpreting experimental data using mathematical models and plots.
  • Drawing conclusions comparing a model to a real exoplanet system.
  • Communicating scientific and mathematical findings to peers.

Age range:
13 – 18 years old


Lesson: 45 minutes

Resource available in:

English, Czech, Danish, Dutch, Greek, NorwegianPortuguese, Spanish and Swedish

Activity 1: Understanding Light Curves

In this activity, students will see an example of real data taken by the Cheops satellite and will use this to see how graphs are scaled to get the most amount of information possible out of the data in them. Understanding the scaling of graphs is an important skill in both mathematics and science.

Students will then be given examples of simulated light curves and guidelines on how to read and interpret the graphs.

They will use the concepts learned throughout the activity to interpret a light curve observed with ESA’s satellite Cheops from WASP 189 b.

Finally, they will investigate how orbital period can be determined from a light curve.

  • Student Worksheet per pupil
  • Pen/pencil
Activity 2: Being an Exoplanet Detective

In this activity, students will apply what they have learnt from analysing the previous light curves and interpret an observation of the TOI-178 exoplanetary system made by Cheops, like a real scientist.

  • Student Worksheet per pupil
  • Pen/pencil

Did you know?

WASP 189 b is a large gas exoplanet that is about 50% bigger in size than Jupiter and in a 2.7 Earth days orbit around a star that is more than 2000°C hotter than our Sun, and almost 2.5 times as big.

Artist's impression of WASP 189 b orbiting a star