As the world reacts to the horrifying news from Norway, host Guy Raz checks in with James Fallows of The Atlantic about this and the week's other big stories, including President Obama's challenge to House Republican leaders on the nation's debt ceiling.

It's another working weekend for the leaders of Congress as the debt-ceiling clock counts down toward Aug. 2. Host Guy Raz gets the Capitol Hill side of the story from NPR's David Welna.

Although House Speaker John Boehner walked away from debt ceiling negotiations with President Obama Friday night, the two sat down with other congressional leaders again Saturday in another attempt to work out a plan to raise the debt limit. NPR's Ari Shapiro talks with host Guy Raz from the White House about how much progress they did, or didn't, make.

President Obama and Speaker Boehner may be the center of attention in Washington right now, but just behind the scenes — and controlling a significant part of the discussion — is anti-tax advocate Grover Norquist.

In 1986, Norquist's group Americans for Tax Reform came up with a simple document with two simple messages:

Singer Amy Winehouse, who mixed pieces of soul, jazz, and gospel into pop ballads, was found dead in her apartment Saturday. Police are so far listing the cause of death as "unexplained." Her career as a musician was often overshadowed by her life off-stage, Winehouse struggled with drugs and alcohol throughout her life.

Winehouse wasn't one to apologize for her substance abuse. In fact, it's a big part of what made the singer so famous, or infamous. Winehouse released her first album, Frank, in 2003, but three years later she shot to super stardom, with her song, "Rehab."

The No. 1 song in America right now is "Party Rock Anthem" by LMFAO. It's also hit No. 1 in Denmark, New Zealand, Mexico, Ireland, Sweden, Australia, Germany, Brazil, the UK ... you get the idea. The duo behind LMFAO — the aformentioned party rockers — are Stefan and Skyler Gordy. Respectively, they are the son and grandson of the legendary Berry Gordy, founder of Motown Records. (For the record: The two are uncle and nephew, not father and son.)

More than 90 people are confirmed dead following Friday's attacks in Norway. The capital city of Oslo was hit by a bomb and then a gunman opened fire at a youth camp. Host Scott Simon speaks with Halvard Sandberg, a reporter for the Norwegian broadcasting corporation, NRK, who is following the story from the site of the camp.

President Obama has summoned Congressional leaders to the White House, after private deficit reduction talks with House Republican leaders broke down Friday night.

On a remote, treeless island 60 miles south of Alaska's Prince William Sound, an old military radar tower has become one of the best bird observation sites in the world.

Hundreds of black-legged kittiwakes nest on the tower. As one researcher has discovered, the seabirds may have a lot of flexibility when it comes to responding to a changing environment.

The hulking, concrete tower on Middleton Island isn't much to look at. But in 1986, a few black-legged kittiwakes took a liking to it.

Authorities in Norway now say more than 80 people were killed Friday at a conference for young people shortly after a massive explosion killed at least seven people in nearby Oslo. It's believed the two incidents are related.