8A70.82 - Protoplanets and Planetshine

Code Number:
Demo Title:
Protoplanets and Planetshine
Planet rate of cooling vs. diameter
Area of Study:
1, 2, and 4 inch diameter aluminum balls with stand, Hot Plate, Pot, IR camera, gloves and safety glasses.

Place the three balls into the pot filled with water and bring to a boil for at least 10 minutes.  Put the balls into the stand so that they are all at approximately the same distance from the IR camera.  View the balls during the course of a class period and observe the cooling rates of each size ball directly with the camera.  This experiment will take at least 30 to 50 minutes for best results.  

Note also that you will observe some "planetshine" during this experiment.  

  • Dulli Chandra Agrawal, "Earthshine, Moonshine, Albedos, Climate …", TPT, Vol. 56, #6, Sept. 2018, p. 406.
  • Sean M. Andrews, "The Structures of Protoplanetary Disks", Physics Today, Vol. 74, #8, Aug. 2021, p. 36.

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