I was recently browsing the Wikipedia page on sunglasses (http://en.wikipedia.org/wiki/Sunglasses) and one of the topics it covered was the necessity of wearing sunglasses in space. Yes, you heard that right…sunglasses in space! I never really considered this before so I thought I’d take a few minutes and summarize the information for today’s post!
Apparently sunglasses are needed because the sunlight in space is exponentially more harmful than the sunlight we experience here on Earth. The reason is that our atmosphere actually filters out much of the harmful UV rays of the sun before it ever reaches our eyes. Astronauts actually need to wear their space shades both inside and outside of the space craft. Specifically, inside they typically wear somewhat standard shades with dark lenses, and outside their helmet visor serves the purpose.
NASA mandates that all sunglasses used for space travel meet certain parameters or requirements. Obviously the lenses must offer top-of-the-line protection from UV rays and even infrared radiation, and the frames for space sunglasses also need to be heavy duty. NASA requires that the frames are flexible yet durable, and form fitted, so they do not get loose or dislodged due to the lack of gravity.
Apparently the first style worn on the moon was a pair of Aviators. These were worn during the first moon landing in ’69 (Apollo 11). The lenses were specially made from dye and zinc oxide (absorbs UV rays and is also found in sun screen). Today, the standard NASA sunglasses feature very dark lenses, extremely lightweight frames, and are free from small parts like nuts or screws that can dislodge while floating.