Are there proof of aliens or life forms in galaxies?

#7

Aliens, UFOs, little green men: Whatever you call it, life that did not start on the Earth has yet to be found, but a number of respected scientists speculate that extraterrestrial life exists. Some such as Frank Drake have even attempted to estimate the number of civilisations in our galaxy based on what we know about the Universe and life on Earth.
Scientists have also identified places in the Solar System such as Jupiter's moon Europa that have the potential to support life. Future missions to these places may find some form of life.