This is SCIENCE FRIDAY. I'm Joe Palca, sitting in for Ira Flatow. If you add it up, we spend a lot of time sleeping, about a third of our lives, actually, and it turns out our bodies don't just power down as we slumber. Research is showing that sleep plays an important role in how our brains process and store the information that we learn throughout the day.
You know the theory that a big collision, a comet or an asteroid, something like that, helped kill off the dinosaurs? The idea has been around for a while. But this week, new research published in journal Science provides more accurate dates for the giant impact and the dino demise.
This is SCIENCE FRIDAY; I'm Joe Palca. Do you ever get the feeling you're being watched? These days if you're not careful, your phone knows where you are, and there's a good chance somebody else does, too. Or you've noticed that the ads on sites you visit are starting to look a little too personalized, like how did they know I was planning a vacation to New Orleans.
Toyota and BMW have formed an alliance to work on fuel cell cars. So have Daimler, Ford, and Nissan, with hopes of having cars on the road by 2017. But why now, and what obstacles still stand in the way? Jennifer Kurtz discusses the current state of hydrogen fuel technology.
An asteroid the size of an office building will zoom close by Earth next week, but it's not on a collision course, NASA says.
Still, some people think this near-miss should serve as a wake-up call.
"It's a warning shot across our bow that we are flying around the solar system in a shooting gallery," says Ed Lu, a former astronaut and head of the B612 Foundation, a nonprofit dedicated to protecting humanity from asteroids.
The asteroid known as 2012 DA14 was first spotted last year by astronomers in Spain. It's thought to be about 150 feet across and made of rock.
Iran's government on Thursday made clear it has no interest in direct talks until the U.S. eases sanctions that have been squeezing Iran's economy. But the Obama administration isn't budging and says the ball is in the Iranians' court.
The suspicion that Iran wants to make a nuclear weapon is the rationale for the sanctions as well as for veiled threats of U.S. or Israeli military action if those sanctions fail.
Originally published on Fri February 8, 2013 2:50 pm
Before they end up filleted and sautéed on your dinner plate, salmon lead some pretty extraordinary, globe-trotting lives.
After hatching in a freshwater stream, young salmon make a break for the ocean, where they hang out for years, covering thousands of miles before deciding its time to settle down and lay eggs in their natal stream.
So how do these fish find their way back to their home river?
Some 66 million years ago, about 75 percent of species on Earth disappeared. It wasn't just dinosaurs but most large mammals, fish, birds and plankton. Scientists have known this for a long time just from looking at the fossil record. If you dig deep enough, you find lots of dinosaur bones. And then a few layers up, they're gone.
But scientists couldn't figure out exactly what had caused this phenomenon. Of course, there were lots of theories.