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Later this week, a retired NASA satellite the size of a school bus will finally fall back towards Earth after orbiting the planet for two decades. Most of it will burn up in the atmosphere. But about two dozen pieces are expected to hit the ground — somewhere.

And the biggest piece will weigh about 300 pounds.

If that's got you worried, NASA emphasizes that in the history of the space age, there have been no confirmed reports of falling space junk hurting anyone. But that doesn't mean no one has ever been hit.

NASA needs to hire a few more astronauts. That's according to a panel of outside experts enlisted by the agency to review the size of the astronaut corps now that the space shuttles are retired. (The panel's report is posted here.)

A physicist named Dmitri Denisov walks up wooden steps to the top of something that looks sort of like an abandoned railroad bed.

"Wow, look, it's beautiful," Denisov says, gazing out at a pond. "I didn't even know about these flowers."

The tall mound of dirt he's standing on stretches off into the distance, forming a huge circle nearly four miles around — and the inside of this ring is filled with acres of restored prairie.

The controversial "polarbeargate" investigation into Arctic researcher Charles Monnett originated when allegations of scientific misconduct were made by a "seasoned, career Department of the Interior" employee.

That's according to a new letter sent to Sen. James Inhofe (R-OK) from the Department of the Interior's Office of Inspector General.

The polar bear scientist who has spent more than a month suspended from his government job has now been told that he should report back to work on Friday — although NPR has learned that his job is changing and he will no longer manage federal contracts.

"Chuck is planning to go to work. He just doesn't know what the work is going to be," says attorney Jeff Ruch of Public Employees for Environmental Responsibility, which is providing legal representation for wildlife biologist Charles Monnett.