Reaching Ultra-Low Temperatures

  • By Richard Pommier Swanson
  • Posted 01.08.08
  • NOVA

Pioneers in the quest to reach absolute zero relied on a technique known as the "cascade" process. By repeating a certain sequence that involved the cooling, compression, and evaporation of various liquids and gases, scientists approached ever closer to absolute zero, the lowest possible temperature. In this interactive, undertake your own three-step cascade and see if you can choose the right combination of gases to liquefy oxygen.

Launch Interactive

In our virtual chemistry lab, use the "cascade" process to achieve dramatically lower temperatures.

This feature originally appeared on the site for the NOVA program Absolute Zero.

Richard Pommier Swanson is the former Science Content Director for PBS's DragonflyTV. He holds degrees in Education and the History of Science and Technology from the University of Minnesota.



©2007 Meridian Productions and Windfall Films

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