• Question: How does suntan lotion work?

    Asked by Science Lover to Jim, Scott on 18 Mar 2016.
    • Photo: Jim Barrett

      Jim Barrett answered on 18 Mar 2016:

      Hmm, this isn’t my area of expertise. If I had to guess, I would say that it must contain certain chemicals that are good at stopping UV rays (the dangerous ones) from getting to your skin.

    • Photo: Scott Lawrie

      Scott Lawrie answered on 18 Mar 2016:

      The primary ingredient of sunscreen is Titanium Dioxide. This and other chemicals in the lotion absorb and reflect the UV in sunlight so it doesn’t get through to your skin.

      Here’s a fun fact: as well as fusing hydrogen to helium in the core, stars do a lot of chemical reactions in their upper atmospheres. Some stars have a lot of titanium and oxygen in them so actually make their own titanium-dioxide sunscreen: a Sun protecting itself from its own UV rays! 😎