We do not have evidence yet that we are not alone in the universe, although some people think there is evidence hidden in Area 51 in New Mexico. Many scientists and non-scientists believe there is a possibilty that there are other life forms in the universe.
Astronomers are constantly searching for clues of other life forms in the universe. They search by looking for radio frequencies in the far corners of the universe. We have found planets in the universe such as Kepler-452b that have the potential to sustain life but we have not been able to detect life there yet.
