When the United Kingdom voted to leave the European Union last month, the seaside town of Port Talbot in Wales eagerly went along with the move. Brexit was approved by some 57 percent of the town's residents.

Now some of them are wondering if they made the wrong decision.

The June 23 Brexit vote has raised questions about the fate of the troubled Port Talbot Works, Britain's largest surviving steel plant — a huge, steam-belching facility that has long been the town's biggest employer.

Solar Impulse 2 has landed in Cairo, completing the penultimate leg of its attempt to circumnavigate the globe using only the power of the sun.

The trip over the Mediterranean included a breathtaking flyover of the Pyramids. Check it out:

President Obama is challenging Americans to have an honest and open-hearted conversation about race and law enforcement. But even as he sits down at the White House with police and civil rights activists, Obama is mindful of the limits of that approach.

"I've seen how inadequate words can be in bringing about lasting change," the president said Tuesday at a memorial service for five law officers killed last week in Dallas. "I've seen how inadequate my own words have been."

Mice watching Orson Welles movies may help scientists explain human consciousness.

At least that's one premise of the Allen Brain Observatory, which launched Wednesday and lets anyone with an Internet connection study a mouse brain as it responds to visual information.

The FBI says it is giving up on the D.B. Cooper investigation, 45 years after the mysterious hijacker parachuted into the night with $200,000 in a briefcase, becoming an instant folk figure.

"Following one of the longest and most exhaustive investigations in our history," the FBI's Ayn Dietrich-Williams said in a statement, "the FBI redirected resources allocated to the D.B. Cooper case in order to focus on other investigative priorities."

This is the first in a series of essays concerning our collective future. The goal is to bring forth some of the main issues humanity faces today, as we move forward to uncertain times. In an effort to be as thorough as possible, we will consider two kinds of threats: those due to natural disasters and those that are man-made. The idea is to expose some of the dangers and possible mechanisms that have been proposed to deal with these issues. My intention is not to offer a detailed analysis for each threat — but to invite reflection and, hopefully, action.

Alabama authorities say a home burglary suspect has died after police used a stun gun on the man.  Birmingham police say he resisted officers who found him in a house wrapped in what looked like material from the air conditioner duct work.  The Lewisburg Road homeowner called police Tuesday about glass breaking and someone yelling and growling in his basement.  Police reportedly entered the dwelling and used a stun gun several times on a white suspect before handcuffing him.  Investigators say the man was "extremely irritated" throughout and didn't obey verbal commands.

It can be hard to distinguish among the men wearing grey suits and regulation haircuts on Pennsylvania Avenue in Washington. But David Margolis always brought a splash of color.

It wasn't his lovably disheveled wardrobe, or his Elvis ring, but something else: the force of his flamboyant personality. Margolis, a graduate of Harvard Law School, didn't want to fit in with the crowd. He wanted to stand out.

Montgomery Education Foundation's Brain Forest Summer Learning Academy was spotlighted Wednesday at Carver High School.  The academic-enrichment program is for rising 4th, 5th, and 6th graders in the Montgomery Public School system.  Community Program Director Dillion Nettles, says the program aims to prevent learning loss during summer months.  To find out how your child can participate in next summer's program visit Montgomery-ed.org

A police officer is free on bond after being arrested following a rash of road-sign thefts in southeast Alabama.  Brantley Police Chief Titus Averett says officer Jeremy Ray Walker of Glenwood is on paid leave following his arrest in Pike County.  The 30-year-old Walker is charged with receiving stolen property.  Lt. Troy Johnson of the Pike County Sheriff's Office says an investigation began after someone reported that Walker was selling road signs from Crenshaw County.  Investigators contacted the county engineer and learned signs had been reported stolen from several roads.

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The Oldest Rock In The World Tells Us A Story

Jan 11, 2013
Originally published on January 11, 2013 1:51 pm

It's hard to imagine how this teeny little rock — it's not even a whole rock, it's just a grain, a miniscule droplet of mineral barely the thickness of a human hair — could rewrite the history of our planet. But that's what seems to be happening.

What is this? It's a zircon, from the Persian word "zargun" meaning "golden colored," an extremely durable mineral found all over the world. This one turned up in a dry, hilly region of Western Australia. It was sitting inside a larger rock, and when scientists checked, it turns out this little grain formed around 4.4 billion years ago. That would make it the oldest rock we've ever seen on this planet, old enough to know secrets about early Earth, old enough to tell us a little something about how life started here.

After all, this planet, geologists say, is only 4.5 or 4.6 billion years old. So this little grain has been around since almost the beginning — but not quite.

It's about 150 to 300 million years short. No surface rocks survive from that earliest time because back then, we figure, volcanoes were blowing up constantly, rocks were being heated, vaporized, melted, pulled down into the earth. There were oceans of burning lava everywhere; asteroids were crashing in from above, setting the air on fire. In the beginning, Earth was not a nice place.

This period has a name; it's called the Hadean Eon, from the ancient Greek, Hades — basically, a polite term for "hellish." Hell melted all the rocks on the Earth's surface, and when it's as hot as Hades, you can't have life, either. The Earth had to wait for its first living creature until later — till things cooled and quieted down. That, anyway, is what we used to think.

What The Little Rock Is Telling Us ...

... Until scientists took a closer look at this grain, this pebble. (I can't tell you how amazed I am to tell you what I'm about to tell you ... sometimes the sheer intellectual audacity of these sciencey tales makes my eyes bug).

When geochemists Bruce Watson and Mark Harrison looked more closely at this grain, they could see where it "started." Crystals are minerals that grow, or harden from a hotter, liquid state, and this crystal got its start on the lower left, in the spot marked "core."

Then, as things cooled, this rock grew, adding more and more bands. You can see those bands, angling off to the right. Here's the thing about rock formation: As crystals grow, they pick up other minerals, whatever's in their path. It's like they're plucking hitchhikers off the road. When this little pebble grew, it grabbed on to little bits of titanium.

The Titanium 'Thermometer'

Geochemists know that zircons will grab more titanium when it's hotter, less titanium when it's colder, so if you count your titanium concentrations, you can figure out how hot it was when the rock formed: X amount of titanium, for example, means it was 600 degrees Celsius when it grew; Y amount of titanium means it was 350 degrees Celsius. Scientists call this equation "the titanium thermometer."

So Watson and Harrison counted titanium concentrations in a bunch of these very old zircon grains, matched them to the thermometer, and discovered that when these zircons formed, the temperatures ranged from about 680 degrees Celsius, plus or minus 20.

To geologists, this was big news, like finding a swimming team in what you thought was a desert.

Rocks that crystallize at these temperatures have been exposed to water. This is something geologists know. Says Professor Watson:

"Any rock heated in the presence of water — any rock, at any time, in any circumstance — will begin to melt at between 650 and 700 degrees. This is the only terrestrial process that occurs so predictably."

So, all of a sudden, here was evidence that the red hot, lava-laced, boiling, lifeless Earth of 4.4 billion years ago had water on it! What's more, Watson says, "we feel our results point more strongly toward the idea of surface water."

Oceans, maybe!

That is "a radical departure from the conventional wisdom," says Professor Harrison. It suggests that even though meteors and asteroids were bombarding the Earth, even though volcanoes were highly active, there must have been intervals — early, early on — maybe in the first 150 million years of Earth history — where the Earth could catch a breath, quiet down and create an ocean.

And, yes, every so often a monster asteroid would blow that ocean into the sky, but maybe not the whole ocean? Maybe on some corner of the planet, enough water remained to allow a heat-loving microbe to form.

OK, you say, but what's the point? Why are your eyes bugging?

Is Life Like A Racehorse? Primed? Ready To Run?

Here's why: It is now possible to imagine that life began on Earth almost as soon as the Earth began — that life (in the presence of water) is, if not inevitable, at least very insistent. Once you've got a planet with water — BINGO!

If that's true, chances for life in the universe suddenly improve — dramatically.

Here on Earth, life could have formed, been blown away, then formed again — and one of those times, down at the bottom of some temporary ocean, sitting by a warm vent — it stayed.

That's what this teeny chip of a rock is now allowing us to think: that life has such potency, such urgency, that as soon as life is possible — life happens!

That's a mighty big story to find in a pebble.


Professor Bruce Watson's quotes come from an interview here conducted by Rebecca Lindsey and David Morrison in 2006. Mark Harrison is quoted in Craig Childs' new book, Apocalyptic Planet, Field Guide to the Everending Earth. The latest puzzler for early Earth historians is how could there have been liquid water on the Earth's surface 4.5 billion years ago when the sun was so much dimmer? Why didn't the oceans freeze? Radiolab regular Carl Zimmer weighed in on that one on his blog The Loom.

Copyright 2013 National Public Radio. To see more, visit http://www.npr.org/.