A team at the University of Washington and the University of Bern has computationally simulated more than 200,000 hypothetical Earth-like worlds all in orbit of stars like our sun. As they report in a paper accepted to the Planetary Science Journal and submitted Dec. 6 to the preprint site arXiv, on these simulated exoplanets, one common feature of present-day Earth was often lacking: partial ice coverage. About 90% of these potentially habitable hypothetical worlds lacked partial surface ice like polar caps.









