NASA is sending a probe to explore a strange object a billion miles beyond Pluto

Even as the Juno mission made history by successfully coming into orbit around Jupiter, NASA had its eyes on other ways to push the boundaries of our knowledge about the universe around us.

The agency has approved a proposal from the New Horizons team to send the spacecraft - which was first sent to explore Pluto - to 2014 MU69. That's the completely uninspiring name of a hunk of rock in the Kuiper Belt, the ring of icy rubble leftover from the birth of the solar system.

Pluto also hangs out in the Kuiper Belt, but visiting 2014 MU69 will send the probe almost a billion miles from Pluto.

Astronomers think 2014 MU69 is about 30 miles across and almost 44 times farther away from the sun than Earth is. And that 2014 in the name isn't random: It's the year astronomers first saw it, which means New Horizons is now heading out to something we didn't know existed when the spacecraft launched in 2006.

New Horizons has actually been headed toward 2014 MU69 since October. But it needed NASA's approval to keep heading out there. Visiting 2014 MU69 will take the probe much deeper into the Kuiper Belt.

The spacecraft hasn't exactly been twiddling its robotic thumbs since its flyby of Pluto last summer.

This spring, it spotted another Kuiper Belt object, catchily named 1994 JR1. The measurements New Horizons took allowed astronomers to pinpoint the object's location and how quickly it rotates.

The mission extension will also let New Horizons swing by more than a dozen other Kuiper Belt objects along the way. Those flying visits will let the spacecraft take measurements similar to those it took of 1994 JR1.

In order to get NASA's okay for the 2014 MU69 visit, the New Horizons team had to put together a detailed proposal outlining what they'd learn from the trip. Even with the agency's go-ahead, the fate of the jaunt out to 2014 MU69 still depends on how NASA's budget shakes out for 2017 and 2018.

If everything goes well, New Horizons would reach 2014 MU69 on January 1, 2019.

Even then, New Horizons wouldn't be the most well-traveled spacecraft. That title goes to Voyager 1, which launched in 1977 and officially left the solar system in 2012.

It can still send back data and likely will continue to be able to into the early 2020s, but it isn't visiting specific objects.

That distinction let Alan Stern, one of the leaders of the New Horizons mission, to declare that while the 2014 MU69 flyby "probably won't be as dramatic as the exploration of Pluto, it will be a record-setter for the most distant exploration of an object ever made."

"It will also be a [Kuiper Belt object] science bonanza," he added, "that's unlikely to be repeated for decades."