In a few days, while Earth rings in another orbit around the sun, a robotic ambassador will be flying close to a small ball of rock and ice deep in outer space. Called 2014 MU69, the mysterious object is more than 43 times farther from the sun than Earth—meaning that if all goes to plan, it will soon become the most distant object that humans have ever explored.

MU69, also dubbed Ultima Thule (pronounced Ul-tee-ma TOO-ly) by the mission team, is the first solar system object discovered after its robotic visitor launched: The celestial body was found in images from the Hubble Space Telescope while NASA's New Horizons probe was already en route toward its historic flyby