Michelle D’urbano
VENUS and Mars are the closest we will ever come to controlled experiments for Earth. Take three rocky planets, two roughly the same mass, one about one-tenth of that mass. Add water. Make one of the big planets a little closer to your star and the small one a little further out. Now wait 4 billion years and observe.
This is a golden age of comparative planetology. Spacecraft within our solar system, combined with new awareness of exoplanets, are bringing the diversity of planets into focus, which also gives us a new understanding of our home world. As a comparative planetologist, I …
