On the fifth anniversary of its historic flyby of Pluto, the New Horizons mission is looking back on its greatest discoveries while it looks ahead to its next encounter.

Prior to this mission, our best images of Pluto came from Hubble, and it saw Pluto as nothing more than a smudge a few pixels across. With New Horizons’ high-resolution mapping of one side of Pluto and medium resolution imaging of the entire world, we find ourselves drowning in new ideas about this icy world. 

Here are the ten facts Pluto scientists find the most amazing: 

1. Pluto has a “heart,” and it drives activity on the planet
2. There’s probably a vast, liquid, water ocean sloshing beneath Pluto’s surface
3. Pluto may still be tectonically active because that ocean is still liquid
4. Pluto was — and still may be — volcanically active
5. Glaciers cut across Pluto’s surface even today, and they’ve done so for billions of years
6. Pluto has heat convection cells on its giant glacier Sputnik
7. Pluto has a literal beating “heart” that controls its atmosphere and climate
8. Pluto has dunes
9. Pluto and Charon have almost no little craters, and that has some big implications
10. Charon had a volcanic past, and it could be key to understanding other icy worlds

The New Horizons spacecraft is still healthy and has some fuel remaining that can be used to direct it near yet another Kuiper Belt Object (KBO), but for that to happen, scientists need to find one with an orbit that gets it close enough to New Horizons’ path that a flyby is possible. Space is mostly empty, and finding the next new target is an ongoing process. Currently, an international team is using the Subaru Telescope in Hawaii to search for just the right KBO, and we here at the Daily Space wish them all the luck in the solar system.

More Information

NAOJ news article 

Five Years After New Horizons Flyby, 10 Cool Things About Pluto (JHUAPL)