MISSED BEAUTY:

A "cloud on the horizon" means that something bad is about to happen. Meanwhile, someone with their "head in the clouds" is thoroughly out to lunch. As Gavin Pretor-Pinney points out in today's talk, clouds get a bad rep when it comes to language.

"But I think they're beautiful, don't you?" he says. "It's just that their beauty is missed because they're so omnipresent, so commonplace that people don't notice them ... unless they get in the way of the sun."

Pretor-Pinney is the founder of the Cloud Appreciation Society and, in this talk, he asks each of us to do something we excelled at when we were kids -- looking up at the clouds and letting our imaginations run wild. He shows many evocative cloud formations -- some created by specific, named types of clouds -- and calls on us all to take part in this global Rorschach test. To that end, the Cloud Appreciation Society (which has 32,000+ members) last week released a CloudSpotter iPhone app that allows people to capture and share their own cloud images. Bonus: NASA will use anonymous data from the app to help calibrate its cloud-observing satellites.

Below, Pretor-Pinney (and a few guests) shares a few cloud images with the TED Blog.

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