Later this week, a small and utterly mysterious world will receive its first interplanetary visitor.

Early Friday morning, NASA’s Dawn spacecraft is scheduled to slip into orbit around Ceres, the largest body in the asteroid belt. Covered in strange, unexplained bright spots, Ceres is not just a normal, potato-shaped asteroid.

In fact, it’s not an asteroid at all – it’s a dwarf planet, just like Pluto. And it will be the first dwarf planet ever explored by an orbiting spacecraft.

“Every time we visit a new object, be it a planet or a satellite, we are always surprised,” said Charles Elachi, director of the Jet Propulsion Laboratory, during