* The big one? New tremors incite new quake fears at Yellowstone.
* And speaking of global disasters: microscopic diamonds point to a North American comet impact nearly 13,000 years ago.
* Joel Achenbach talks 'fireballs in the sky.'
* "A sustainable global food system in the 21st Century needs to be built on a series of 'new fundamentals.'"
* And while I don't like to be an alarmist, I am slightly wary about igniting a man-made star. (Courtesy MGK.)
* Using satellites to track down undiscovered ancient Egyptian ruins.
* China says it has unearthed a major dinosaur find.