Despite our best efforts, Earth is still the only known planet in the universe to harbor any kind of life. Though plenty of our attention in this hunt has been focused on studying potentially habitable exoplanets, this question is concerned with the likelihood of finding extraterrestrial life in our own cosmic backyard.

Will any conclusive evidence for extraterrestrial life, past or present, be discovered within our Solar System by 2050?

Resolution details:

• To resolve positive, a scientific consensus must be reached that life exists or has existed anywhere in our Solar System besides Earth, as judged by Metaculus admins. Resolves negative if there is no sufficiently strong evidence for such by 2050.

• The life in question can be related to Earth life, i.e. sharing a common origin with us, but must not have been placed there by humans. For example, if we find Europan life that turns out to have shared a common ancestor with Earth life millions or billions of years ago, that’s fine. But if we accidentally or otherwise contaminate Mars with our spacecraft, that won’t count.