A new study suggests that, without plate tectonics and the right balance of carbon dioxide and oxygen, advanced alien civilizations may be exceedingly rare.

No near neighbors: Closest technologically advanced aliens may be 33,000 light-years from Earth

Source: space
Source Link: https://www.space.com/space-exploration/search-for-life/no-near-neighbors-closest-technologically-advanced-aliens-may-be-33-000-light-years-from-earth