Ok, let's assume we find a warm, watery planet like Earth's within ~20 light years, and we figure out a way to travel >= 50% the speed of light, making it somewhat reasonable to get there. If the planet's gravity is greater than 10% different from Earth's, or its Day/Night cycle is much different from Earth's, wouldn't it still be a nightmare to live on.
Anatomically modern humans have lived on Earth for 200,000 years, and the creatures we descended from have lived on Earth for 541 million years. Stuff as dumb as the moon cycles affect us. How are we going to live somewhere that isn't exactly Earth?
Anatomically modern humans have lived on Earth for 200,000 years, and the creatures we descended from have lived on Earth for 541 million years. Stuff as dumb as the moon cycles affect us. How are we going to live somewhere that isn't exactly Earth?