"The specular reflection our instruments recorded of the lake suggests parts of Io's surface are as smooth as glass, reminiscent of volcanically created obsidian glass on Earth," Bolton said.

After a knuckle-bashing start with its long oars, I’m soon gliding across the glassy surface of Sagamore Lake. “You’re ...

NASA's Juno spacecraft found Io’s surface is as smooth as glass, just like volcanically created obsidian glass ...