Kepler rejected the idea that the enormous scale of the cosmos suggested that mankind is less important than in the cozier Aristotelian-Ptolemaic model.
A planet needs more than location in a habitable zone. It needs the right ingredients, and salt has a surprising role.
Enceladus is an especially fascinating case. Nearly 100 geysers of water ice are currently jetting out of its south pole at supersonic speed.
The hexagon on Saturn performs no function. Columnar basalt doesn’t say anything. Snowflakes don’t carry a message. They are mere emergent phenomena.
Jupiter’s moon Europa, somewhat smaller than Earth’s moon, may have surface water and organic chemicals, researchers say.