Skip to content
Skip to main content

About this free course


Download this course

Share this free course

An introduction to exoplanets
An introduction to exoplanets

Start this free course now. Just create an account and sign in. Enrol and complete the course for a free statement of participation or digital badge if available.

2.5  Circles, radii and area

Astronomers use maths to interpret the light they collect. One very useful bit of maths for astronomy is the area of a circle. Astronomy features spherical objects like stars and planets and you have already seen that when we view them we see their cross-section as a circle. In the next section you’ll see how the area of a circle is calculated.