The tusk from a mammoth that lived 16,000 years ago in the Seattle area unearthed earlier this week appears to be the largest, most intact ever found in the region.
It's thought to be from a Columbian mammoth, a subgroup of woolly mammoths, and is considered to be a pretty rare find. Construction workers stumbled on it as they were digging the foundation for an apartment complex in the city's South Lake Union neighborhood.
The world's largest solar power plant, made up of thousands of mirrors focusing the sun's energy, has officially started operations in the Mojave Desert, just inside southeastern California near the border with Nevada.
The $2.2 billion, 400-megawatt Ivanpah Solar Electric Generating System, which covers 5 square miles and has three 40-story towers where the light is focused, is a joint project by NRG Energy, Google and BrightSource Energy. The project received a $1.6 billion federal loan guarantee.
We're doomed to be miserable if we don't get what we want — right? Not quite, says psychologist Dan Gilbert. He says our "psychological immune system" lets us feel truly happy even when things don't go as planned.
When are humans most happy? To answer this question, researcher Matt Killingsworth built an app, Track Your Happiness, that let people report their feelings in real time. Among the results: We're often happiest when we're lost in the moment.
The second major volcanic eruption in as many weeks in Indonesia has killed at least three people and forced the evacuation of tens of thousands on the island of Java, as Mount Kelud spewed ash and debris 12 miles into the sky.
Thursday night's eruption of the volcano, located 50 miles southwest of the country's second-largest city of Surabaya, could be heard up to 125 miles away, Indonesia's disaster agency says, according to The Associated Press.
Termites can build huge, elaborate mounds that rise up from the ground like insect skyscrapers; scientists have now created little robots that act like termites to build a made-to-order structure.
"Termites are the real masters of construction in the insect world," says Justin Werfel of the Wyss Institute for Biologically Inspired Engineering at Harvard University. "The largest termite mound on record was 42 feet tall."