The planet Venus is seen crossing the sun in June 2004 as photographed through a telescope at Planetarium Urania in Hove, Belgium. The earliest known observation of such a transit was in 1639 by English astronomer Jeremiah Horrocks.
This map provided by NASA shows the visibility for Tuesday's transit of Venus. Click here for information on the best viewing times for your location.
Less than 250 years ago, the brightest minds of the Enlightenment were stumped over how far the Earth is from the sun. The transits of the 1760s helped answer that question, providing a virtual yardstick for the universe.
Protesters in Nice, France, hold banners depicting then-French President Nicolas Sarkozy and President Obama before a November 2011 G-20 summit where global financial issues were discussed. Sarkozy has since lost re-election; some political scientists say economic problems in Europe also could play an unprecedented role in the upcoming U.S. election.
Credit Chip Somodevilla / Getty Images
Volunteers unfurl a banner with the Preamble to the Constitution during a demonstration against the Supreme Court's Citizens United ruling on campaign finance rules at the Lincoln Memorial in Washington, D.C., Oct. 20, 2010.
Credit Pablo Martinez Monsivais / AP
President Obama holds an online meeting from Facebook headquarters in Palo Alto, Calif., April 20, 2011. One political science professor says Obama's digital campaigning skills could make a difference in November.
It's more bad news for Facebook today. A poll by Reuters/Ipsos found that most of its users are not swayed by its advertisements.
Four out of five users surveyed said they had never bought a product based on advertising they saw on the network. What's more, the online poll revealed that "34 percent of Facebook users surveyed were spending less time on the website than six months ago, whereas only 20 percent were spending more."
A new expose by The Times-Picayune of New Orleans calls Louisiana the "world's prison capital."
The state imprisons more people per capita than any other state or country in the world, with one out of every 86 adults behind bars. Its rate of incarceration is three times higher than Iran's and 10 times higher than Germany's.
How did Louisiana double its prison population in the past 20 years? And what differentiates it from other states?
Nobel Prize-winning economist Joseph Stiglitz grew up in Gary, Ind. — a city that has weathered many economic storms over the past half-century.
Stiglitz went on to study at Amherst College and MIT, where he received a Ph.D. in economics. He later served on and chaired President Clinton's Council of Economic Advisers and became the chief economist at the World Bank. But even as a child, Stiglitz says, he noticed ways in which the markets weren't working.
Starting today, we're trying something different. We've enlisted Marissa Alioto, an intern on NPR's social media desk, to comb through your comments and highlight those that are smart and insightful and can teach us all something. We know there is a wealth of knowledge there. We expect some of them to be opinion, but we hope others just point out something that moves a story forward. With that here is Marissa:
This is TELL ME MORE from NPR News. I'm Michel Martin. Coming up, during his long and varied career, Oscar winner Morgan Freeman has played everyone from soldiers to servants, from cowboys to criminals - not to mention the almighty. In a moment, he'll tell us what music he plays for inspiration. That's our feature we call In Your Ear, and it's just ahead.
This is TELL ME MORE from NPR News. I'm Michel Martin. Coming up, a picture of military moms breastfeeding their children has gone viral and it's raising questions about what's appropriate for women in uniform. We'll speak with one of the women in the picture about why she did it and the reaction to it. That's in just a few minutes. But first, voters are casting ballots in several states today and many political observers will look to the results for clues about the battle for the White House.
Photos of Air Force moms breast-feeding in uniform recently went viral and sparked debate. The photos were meant to support military moms in breast-feeding. But some critics say the photos are disrespectful to the uniform. Host Michel Martin discusses the issue with active and retired military moms, including one who was featured in the photos.