With temperatures reaching 95°F and an unforgiving sun overhead, would botanist Ellen be able to find a natural sunblock to save the scientists' complexions?

Why does our skin get harmed by the sun?

Three kinds of ultraviolet (UV) light come from the sun:

• Ultraviolet A (UVA) rays are the longest of the three with wavelengths (400-315 nanometers) that penetrate deep into the layers of skin causing tissue damage and wrinkling.
  
  
• Ultraviolet B (UVB) rays have shorter wavelengths (315-280 nanometers) and are known to mainly cause sunburn and skin cancer.
  
  
• Ultraviolet C (UVC) rays are very short (280-100 nanometers) and the ozone layer is designed to protect us from these deadly rays.
  
  

How does our skin become tanned? 

Major funding for Rough Science was provided by the National Science Foundation. Corporate funding was provided by Subaru.

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