Mars - 3.6 Billion BC

So it turns out Mars probably wasn't as lush as we'd like to think it was; only a few hundred million years after the formation of the solar system isn't enough time to get a biota such as Earth's modern one, and it's also really cold. Most of Martian biology was probably aquatic or subterranean.

LOOKS REEEAAALLY COOL THO. And that's gonna be humanity's second home sometime in the future! So save your pennies, so that you may one day kiss Martian soil (don't actually put martian regolith anywhere near your face.)