After decades of global dominance, America's space shuttle program ended last summer while countries like Russia, China and India continue to advance their programs. But astrophysicist Neil deGrasse Tyson, author of the new book Space Chronicles: Facing the Ultimate Frontier, says America's space program is at a critical moment. He thinks it's time for America to invest heavily in space exploration and research.

When a nerve is injured, it's often hard to get it to regrow fast enough to restore function.

But now researchers say they can speed up that process, so that damaged nerves can be healed in days instead of months — at least in rats.

The scientists say they've developed a technique that reconnects the severed ends of a nerve, allowing it to begin carrying messages again very quickly. Usually, severed nerves must regrow from the point of injury — a process that can take months, if it ever happens.

The halls of the State Department are haunted, not by actual ghosts, but by people who might as well be ghosts: whistleblowers, people who angered someone powerful and people who for one reason or another, can't be fired.

"People like me, that the State Department no longer wants, but for some reason can't or won't fire, are assigned to what we call 'hallwalking,'" says author Peter Van Buren.

The Kansas Jayhawks staged a dramatic comeback Saturday to defeat the Missouri Tigers 87-86. Never mind the exciting finish; this may the last time these two teams ever meet.

And it's not the only feud ending this season. College sports has now bid farewell to three of its very oldest rivalries.

A week before Russia's presidential election, we hear a sampling of opinion from citizens traveling to and from Moscow from around Russia's vast territory. NPR's Corey Flintoff caught up with them at three train stations and asked them what their lives have been like under 12 year's of Vladimir Putin's rule and why they will or will not vote to return him to the presidency.

Host Rachel Martin speaks with Nate Silver, who writes the FiveThirtyEight blog for The New York Times, about the mechanics of the GOP primary, the number of delegates apportioned so far and how future contests will determine the delegate count.