Take a Cool Guess—The Fun Quiz on Renewable Energy and Environmental Sustainability. Today’s Topic: What Happens Upstairs

Question: The aircraft we come in contact with on a day-to-day basis flies in the troposphere, i.e., under about 50,000 feet.  Are there aircraft that function in the layer above that, i.e., the stratosphere?  If so, how are they powered and what is their function?

Answer: Can be found at Clean Energy Answers.

Relevance: This new aircraft platform is a great use of solar power and a breakthrough in lithium ion batteries, one that boasts an extremely high specific energy, i.e, gravimetric energy density, obviously extremely important in this application.