Chapter 11 Build a Twilight Photometer, part 2

Next time a Pinatubo-class volcano erupts, amateur scientists will be able to track the height of its aerosol cloud. Chapter 10, “Build A Twilight Photometer, part 1,” showed how to make an ultra-sensitive DIY twilight photometer. In this chapter, you’ll learn how to use a computer spreadsheet to manage and graph your photometer data so you can find the approximate altitude of layers of smoke, dust, smog, and volcanic aerosols in the atmosphere.


  • Twilight photometer and bubble level (see Chapter 10, “Build A Twilight Photometer, part 1”)
  • Digital voltmeter
  • Data logger (optional) recommended
  • Compass or compass rose
  • Computer with Internet access and LibreOffice spreadsheet software (free download ...

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