Twenty years ago, the paranoia that consumed cults like Heaven's Gate existed on the margins of American society. Such beliefs in conspiracies has moved toward the center of our culture, says one expert.
By mid-February in the three great hot and dry deserts of the American West, wildflowers turn stark desert landscapes into a sea of color.
The last ice age led to the rise of the woolly mammoth and the vast expansion of glaciers, but it's just one of many that has chilled Earth throughout the planet's 4.5-billion-year history.