New NASA Interstellar Mission Could Last 100 Years

Nell Greenfieldboyce, NPR

NASA's twin Voyager spacecraft, launched in 1977, have been traveling for so long that they've left our solar system. Amazingly, these venerable probes still talk to Earth, but their plutonium-powered energy supply is getting ever closer to running out.

That's why NASA asked a team of scientists and engineers to come up with a successor mission that could pick up where the Voyagers left off.