Why is the sky blue? 🌞 Sunlight scatters when it hits air molecules in the upper atmosphere, and because blue light has the shortest wavelength it's scattered most strongly. In the 1860s John Tyndall recreated this in the Ri labs using a glass tube, smoke & a beam of light. 1/7
Violet light is actually even more strongly scattered by the atmosphere than blue light. But sunlight is weaker in violet wavelengths compared to blue and the human eye is less sensitive to it, so we see the sky as blue. 6/7
New extra-inning rules are a nice concept when it’s the 9th inning and there’s a giant cloud beginning to eat the blue sky.
The Apple Fire is still burning at 15,000 acres. On the bright side, there’s still plenty of blue sky near the epicenter. @MyDesert
Pro-tip: Don't watch Trump live. Follow the outrage on Twitter while staring at a blue early-evening sky. It is so much healthier, and you don't miss any lowlights.
Mars sky is the opposite of Earth Blue sunrise and sunset Red during the day