National News from NPR

Robert Siegel talks to Amanda Renshaw, editorial director for Phaidon Press, about a 18-pound coffee table book called The Art Museum. Ten years in the making, spanning 3,000 years, and showcasing close to 3,000 of the world's most important and influential art works, it's a virtual art museum in a book. It features art from 650 collections worldwide.

The Greek government is teetering on the brink of collapse Thursday, following the decision of Prime Minister George Papandreou to call off a referendum on the Europe bailout package for his country. The finance minister and other party colleagues have turned against Papandreou, amid talk of a national coalition government to prepare for new elections. Guy Raz talks to Joanna Kakissis, who has the latest from Athens.

President Obama met with Chancellor Angela Merkel of Germany and French President Nicolas Sarkozy on Thursday, the first day of the G-20 summit in France. They discussed efforts to deal with the Europe debt crisis.

Robert Siegel speaks to Mark Mazower, a professor of history at Columbia University and an expert on contemporary Greece, about the tensions between democracy and the need for decisive action in dealing with the euro crisis. Mazower says that the speed of financial markets, and the slowness of the democratic process, has increased this tension during the crisis.

Groupon, the daily deals website, is getting ready for its initial public offering Friday. But is stock in the company itself a good deal? Guy Raz talks with Wailin Wong, a business reporter from the Chicago Tribune, about the Groupon IPO.

In what's becoming a disturbing trend in China, another Tibetan nun has set herself on fire to protest the country's strict control of their religion.

The Free Tibet Campaign says Palden Choetso is second nun to self immolate. Nine monks have done the same since March.

Twentieth-century Russian music is often thought of as dark and brooding, a reflection of life under the thumb of a brutal state. When it was funny, it usually had a kind of gallows humor.

Yet many of the same composers whose concert works often reflected a dark reality also wrote cartoon music for kids. Thursday night, the Brooklyn Philharmonic is playing some of these cartoon scores in Brighton Beach — the heart of the Russian-American community in New York City. For some of its creators, cartoon music offered a certain kind of escape.

To us it sounded like the premise of a particularly cruel reality TV show: Six men are picked to live in a windowless, cramped mock spaceship for 18 months to see how humans would react to conditions similar to what one would expect on a mission to Mars.

Tomorrow, after 520 days of isolation, the hatch will finally be open and the volunteers will return to normal life. With a cost of $15 million, the project, dubbed Mars500, is a serious experiment commissioned by the European Space Agency.