K49KA-D

Grammy Award-winning bluegrass musician Billy Strings performs highlights from "So Much for Goodbyes" and "Highway Prayers.".

The decades-long scientific quest that led to a life-saving treatment for cystic fibrosis.

The lion pride males are injured and the mothers with cubs are left vulnerable after an attack; Xudum, the female leopard, takes risks to find a mate.

Tracking how the polar world is transforming, from scaling jagged peaks to descending deep into the ice sheet.

The philosophical, cultural and political forces driving the global artificial intelligence boom.

Mapping the roots of actress Kate Burton and media mogul Barry Diller.

Sign off.

Benny's toy penguin is swept away by melting snow, transforming a day of sledding into an urgent rescue mission.

Lyla and Everett make a lemonade stand to raise money for the animal shelter; Lyla and Everett learn Double Dutch to become part of a neighborhood crew.

Phoebe, Jay, Grandma Annie and Pete create the family's first recipe for Sunday greens; Phoebe and Jay are excited about their first campout in the courtyard.

Cinderella needs to tell time for the ball, but her clock is broken, so Nina, Abby and Rudy wonder what tool they can use to fix it.

The search for Mr. Splendito tickets is on; the Wombats power-clean a bunch of bikes.

Donkey is disappointed when her friends are away for the day but finds a way to have fun on her own; Donkey wants to be like Fashion Penguin.

Rosie wants to be Mayor for the day; Rosie decides she wants to be a statue.

A series of mishaps gives Alma "the grumps"; Junior wants to play basketball with the big kids and make a basket.

Buzz and Delete try to help when Harmony gets stuck on a math word problem; Buzz and Delete try to make it into the Cyber Book of Records.

Invention may have been used to build the atomic bomb; a 23-pound block of beeswax; French manuscript could be love poems.

Rugby legends Phil Vickery and Martin Offiah take to the antiques trail around Bristol; Phil swaps a rugby ball for a polo stick and Martin finds out about man's first ascent into the skies.

Peanut farm; Pepsi-glazed pork belly with country ham-braised peanuts; boiled peanuts.

The lion pride males are injured and the mothers with cubs are left vulnerable after an attack; Xudum, the female leopard, takes risks to find a mate.

The decades-long scientific quest that led to a life-saving treatment for cystic fibrosis.

News analysis of issues and policy affecting the U.S.

Experts analyze prominent international affairs topics and America's role in a shifting world.

A panel of journalists provides reporting and analysis of the major stories emanating from the United States capital.

An 1830 first printing of "The Book of Mormon," Dallas memorabilia and Tennessee sampler; Ruth, Mantle & Maris-signed baseball.

When a man is killed at her university reunion, Becks finds herself on the wrong side of an investigation.

As Eliot's health deteriorates, he accuses his family of murder; Atticus Pund closes in on his prime suspect.

Cushla and Michael begin a secret relationship that changes everything; as violence and scrutiny close in, Cushla is forced to risk everything for a love that defies the divide.

Grammy Award-winning bluegrass musician Billy Strings performs highlights from "So Much for Goodbyes" and "Highway Prayers.".