An introduction to exoplanets
An introduction to exoplanets

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Week 3: Dawn of the exoplanet era


This week you are going to look at your first exoplanet – the first planet ever discovered orbiting another star. That planet is called 51 Pegasi b. You will learn about how the planet was discovered by measuring tiny changes in the properties of the light coming from the star 51 Pegasi, and you will also find out what kind of planet it is.

Watch the following video in which Carole Haswell talks about how the exoplanet era came about.

Download this video clip.Video player: boc_exo_1_video_week3_carole_upload.mp4
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By the end of this week, you will be able to:

  • interpret the name of an exoplanet
  • describe the characteristics of 51 Pegasi b
  • explain the radial velocity method for detecting planets using the analogy of a see-saw
  • understand that both light and sound are waves
  • understand how the Doppler shift affects wave properties
  • use the website [Tip: hold Ctrl and click a link to open it in a new tab. (Hide tip)] to find a list of planets discovered by the radial velocity method.

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