“It was the Venus I had prayed to, it was my prayer, though I had no such words. They filled my eyes with tears and my heart with inexpressible joy.” -Ursula Le Guin
If you were to rewind the Solar System to the very beginning, with only imperceptibly different initial conditions, how often would Earth emerge looking like it does today: teeming with life? And how often would the other worlds — Venus or even Mars — emerge overflowing with stable, long-term life either instead or in addition to Earth?
While we’ve often assumed that Earth had the right conditions for a likely life-rich outcome, we’re quite possibly biased by where we’ve come of age, and by the fact that we only know our own Solar System in detail. But as exoplanet data continues to improve and pour in, we have a whole world of other possibilities we should remember to consider.