Cracks on the dwarf planet’s icy surface suggest it was warm enough to host a liquid ocean early in its...
The traumatic event may also have seeded the gas giant’s many moons.
It could join the ranks of Pluto and four others in our celestial neighborhood.
Gas might keep the dwarf planet’s subsurface ocean from freezing.
We're under a time crunch.
Short answer: Because we changed the definition of the word “planet” to better fit its meaning.
A good week for space photography
But we won't know until we get there.
New Horizons will soon find out what's up with MU69.
Each and every planet—and one dwarf planet—in our solar system, represented with the single best image ever taken of it....
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