NASA says it has found proof that water shaped the rocks on the left, in a photograph taken by the Mars rover Curiosity (left). For comparison, the agency released an image of rocks from the Earth (right).
Pathfinder, 1997: The first mission to land a rover on Mars, Pathfinder touched down in Ares Vallis, an ancient flood plain in the planet's northern hemisphere. Among the 2.3 billion bits of data sent back by the lander and its rover, Sojourner, were 15 chemical analyses of rocks and soil, which suggested Mars had once had liquid water and a thicker atmosphere.
Spirit, 2010: When NASA's Spirit rover got stuck in Martian sand, it proved to be a lucky break: The spinning wheel churned up soil that provided evidence of rocks formed in the presence of water.
Opportunity, 2004: Opportunity discovered tiny mineral spheres — nicknamed blueberries — poking out of rocks that were likely formed by water. Researchers using Opportunity's science instruments identified them as concretions rich in the mineral hematite, deposited by water saturating the bedrock.
Curiosity 2012: A wider view of the outcrop of a former streambed shows bedrock that scientists believe was likely exposed by meteorites striking the surface of Mars.
Curiosity, 2012: NASA says that water shaped the rocks on the left, in a photograph taken by the Mars rover Curiosity. For comparison, the agency released an image of rocks from the Earth (right).
NASA's Curiosity rover has found definitive proof that water once ran across the surface of Mars, the agency announced today. NASA scientists say new photos from the rover show rocks that were smoothed and rounded by water. The rocks are in a large canyon and nearby channels that were cut by flowing water, making up an alluvial fan.
"You had water transporting these gravels to the downslope of the fan," NASA researchers say. The gravel then formed into a conglomerate rock, which was in turn likely covered before being exposed again.
One night in 1984, British scientist Frances Ashcroft was studying electricity in the body and discovered the protein that causes neonatal diabetes. She says she felt so "over the moon" that she couldn't sleep.
By the next morning, she says, she thought it was a mistake.
But luckily, that feeling was wrong, and Ashcroft's revelation led to a medical breakthrough decades later, which now enables people born with diabetes to take pills instead of injecting insulin.
At the U.N. today, Israeli Prime Minister Benjamin Netanyahu used a graphic to show how far he says Iran will be by mid-2013 in a quest to develop nuclear weapons. He drew the red line to mark where he says Iran must be stopped.
Originally published on Thu October 4, 2012 11:48 am
Israeli Prime Minister laid out in some detail this afternoon his nation's case for taking stronger action against Iran and his nation's response to what he said are "libelous" accusations about how Israel treats Palestinians.
Taking to the stage just minutes after the head of the Palestinian Authority, Benjamin Netanyahu told United Nations delegates this afternoon that Israelis and Palestinians "won't solve our conflicts with libelous speeches at the U.N."
Several states have passed what are known as parent-trigger laws, which give parents a path to make operational changes in failing schools. Education Week reporter Sean Cavanagh talks about where parent-trigger laws are in place and what we know about whether or not they are working.
China has been plagued by political scandal and controversy, just as the Communist government prepares for its once-a-decade transfer of power. It's an important moment for the government, which faces questions about how its economy will be governed and how it will handle deal with foreign powers.
This is TALK OF THE NATION. I'm Neal Conan in Washington. More than 38 million kids get their lunches through the National School Lunch Program, and with more than a third of the nation's youngsters overweight or obese, the cafeteria has become a battleground.
This week, we've been taking time to listen to several world leaders address the U.N. General Assembly in New York with special emphasis on the looming crisis over Iran's nuclear ambitions. We heard from President Obama and Republican presidential nominee Mitt Romney on Tuesday, from Iranian President Mahmoud Ahmadinejad yesterday. Today, Israeli Prime Minister Benjamin Netanyahu addressed the gathering and outlined the situation in stark terms. He warned that Iran will have enough enriched uranium to make a nuclear bomb by next summer.