Seven Earth-Sized Planets

[stevebowers]

I particularly like the images of TRAPPIST-1d and TRAPPIST-1f. A dry, hot Hesperian world and an eyeball-Earth. The one image I disagree with is TRAPPIST-1g; that world is shown as a mini-Neptune, but there is a good chance that TRAPPIST-1g is the most Earth-like of the lot. Instead of having a dense atmosphere, it may have lost a significant amount due to flaring from the star; it should also be heated tidally by the proximity of so many other planets. So it could be warm, with a relatively thin atmosphere, and could be rotating due to spin-resonance. Probably not very Earth-like, but it should be terraformable using OA tech. (most of the others could be terraformed too, but with increasing levels of difficulty.)