Now you see it, now you don’t

Last Friday, in one of its periodic displays of  nerdy humor, Google displaced its usual search page logo with an animated gif celebrating Earth's non-collision with Asteroid 2012 DA14, a 50-meter-wide rock that passed within 28,000 meters of our planet—closer than a geostationary communications satellite. Trouble is, another, much smaller meteor chose the same day to collide with Earth, exploding over the Siberian town of Chelyabinsk Oblast with the force of a half megaton nuclear weapon, and injuring 1,500 people below, mostly from flying glass. Google quickly yanked the animation. "Out of respect for those injured in the extraordinary meteor shower in...