Are comets carriers of exotic biological life forms? And what would happen if Earth moved closer to the Sun, further away, or into the distant solar system?
Are comets carriers of biological life forms that began life on Earth? And how would Earth's environment and biology have developed if the planet had been a different size?
We explore the possibility of life beyond our solar system, including life on giant gas worlds. And if aliens exist, would they necessarily want to communicate with us?