A mission known as NeoWise is scanning the solar system for asteroids whose orbits come close to Earth’s — asteroids that could someday endanger our planet. That wasn’t the craft’s original mission, though. Originally known as WISE, it was designed to study the infrared glow of galaxies, gas clouds, and other objects. When it used up its coolant, two of its cameras shut down. But two others still worked, so scientists gave it the new job.

NeoWise isn’t the only scientific spacecraft to get a new mission.

The Kepler space telescope, for example, spent about three years looking for planets around 150,000 target stars in a single patch of sky. But part of its pointing system failed. So scientists came up with a new mission, called K2. It allowed the craft to peer at different patches of sky for a few months at a time — and discover hundreds of new planets.

Deep Impact watched what happened when it fired a small cannonball into Comet Tempel 1. After that, it was renamed Epoxi and sent toward another comet. Along the way, it kept an eye on several stars with known planets — an effort to learn new details about those worlds.

And another mission, Stardust, captured grains of dust from yet another comet. It swung past Earth to drop off the comet dust, then began its new mission. Known as Next, it flew past Comet Tempel 1 — the same one hit by Deep Impact — to see how the comet had changed — a new job for an old spacecraft.

Script by Damond Benningfield