Infinitely useful EM diagram

(click to enlarge) The talented comics of XKCD dot com

Stunning time-lapse skyscapes

El Cielo de Canarias / Canary sky - Tenerife from Daniel López on Vimeo.

Music: Matti Paalanen , Angel's Tear (Aeon 2) 

The above video was shot solely from the Teide National Park on Tenerife in the Canary Islands over the course of a year.