On Earth, life thrives in some of the most seemingly inhospitable environments. Single-celled organisms like bacteria teem in the hot springs of Yellowstone National Park, where temperatures reach nearly 200

This image was taken near the closest approach point, at a range of 560 kilometers (335 miles) and is the highest resolution picture of Europa that will be obtained by

Results assuming undetected contacts with technoemissions over the past 65 yr. (a) Minimum number nmin of undetected past contacts required to achieve a present-day detectability of at least 95%, as