"Not only is the Universe stranger than we imagine, it is stranger than we can imagine." ~ Sir Arthur Eddington, English Astronomer (1882-1944)
NASA's New Horizons spacecraft spied several features on Pluto that offer evidence of a time millions or billions of years ago when—thanks to much higher pressure in Pluto's atmosphere and warmer conditions on the surface—liquids might have flowed across and pooled on the surface of the distant world.
This feature appears to be a frozen, former lake of liquid nitrogen, located in a mountain range just north of Pluto's informally named Sputnik Planum. Captured by the New Horizons' Long Range Reconnaissance Imager (LORRI) as the spacecraft flew past Pluto on July 14, 2015, the image shows details as small as about 430 feet. At its widest point the possible lake appears to be about 20 miles across.
A lake of liquid nitrogen…now frozen. Mind blown.