Science

You are 200 miles directly above the Martian surface — looking down. This image was taken by the Mars Reconnaissance Orbiter on Jan. 27, 2010. (The color was added later.) What do we see? Well, sand, mostly. As you scroll down, there's a ridge crossing through the image, then a plain, then dunes, but keep looking. You will notice, when you get to the dunes, there are little black flecks dotting the ridges, mostly on the sunny side, like sunbathing spiders sitting in rows. Can you see them?

When Einstein proposed the first cosmological model of the modern era in 1917, he had no reason to suppose that the Universe had a beginning. Everything indicated that the Universe was static and infinitely old, without an "origin" event. (A few redshift measurements made by Vesto Slipher in the United States were inconclusive and probably didn't make it to Europe, anyway.) Everything also indicated that the Milky Way was all there was out there. Other nebulae, seen with telescopes, were considered to be part of our galaxy.

Scientist Barry Commoner, a pioneer in environmental activism, died Sunday. Melissa Block speaks with Michael Egan, environmental historian at McMaster University in Hamilton, Ontario, and author of the book, Barry Commoner and the Science of Survival: The Remaking of American Environmentalism.

Everyone knows that the weather this summer in the United States was a disaster. Temperature records fell faster than knickknacks off a broken bookshelf across much of the country. Vast swaths of the nation were facing "extreme" or "exceptional" drought conditions. And while it is impossible to say with certainty if any particular weather event is caused by climate change, the events of the summer are pretty much exactly what climate scientists have been predicting for decades.

When French peasants stormed the Bastille on July 14, 1789, they weren't just revolting against the monarchy's policies. They were also hungry.

From the French Revolution to the Arab Spring, high food prices have been cited as a factor behind mass protest movements. But can food prices actually help predict when social unrest is likely to break out?

Medicine in the United States is, in part, safeguarded by the Food and Drug Administration (FDA). The FDA serves admirably as a protection against charlatans and ineffective treatments through the use of clinical trials that filter out dangerous drugs and identify safe, effective therapies.

When there's something really wrong with a published study, the journal can retract it, much like a carmaker recalling a flawed automobile.

But are the errors that lead to retractions honest mistakes or something more problematic?

A newly published analysis finds that more than two-thirds of biomedical papers retracted over the past four decades were the result of misconduct, not error. That's much higher than previous studies of retractions had found.

There was a time — and it wasn't that long ago — when kids would leave home on a summer morning and roam free. "I knew kids who were pushed out the door at eight in the morning," writes Bill Bryson of his childhood in the 1950s, "and not allowed back until five unless they were on fire or actively bleeding." That's what kids did. They went out. Parents let them, and everybody did it. "If you stood on any corner with a bike — any corner anywhere — more than a hundred children, many of whom you had never seen before, would appear and ask you where you were going," Bryson writes.

As you take in your next breath of air, you can thank a form of microscopic marine life known as plankton.

They are so small as to be invisible, but taken together, actually dwarf massive creatures like whales. Plankton make up 98 percent of the biomass of ocean life.

"This invisible forest generates half of the oxygen generated on the planet," Chris Bowler, a marine biologist, tells Guy Raz, host of weekends on All Things Considered.

And, as climate change alters the temperature and acidity of our waters, this mysterious ocean world may be in jeopardy.