An introduction to exoplanets
An introduction to exoplanets

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Week 5: How to measure your exoplanet


Over the last two weeks you’ve learned two methods for detecting exoplanets: radial velocity and transits. This week, you’re going to look in more detail at the first transiting exoplanet to be discovered, HD 209458 b, and learn how astronomers have measured its properties.

Watch the following video with Carole Haswell.

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By the end of the week, you will be able to:

  • know HD 209458 b was the first transiting exoplanet
  • explain how astronomers measure an exoplanet’s size and mass
  • appreciate the importance of transiting exoplanets
  • describe the numbers of exoplanets discovered by the transit and radial velocity methods
  • know that close-in exoplanets are more likely to transit.

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