Since the first time we sent a probe into space we’ve been “aliens” on all of the worlds we’ve visited. We’ve had HUMAN ALIENS walking around the MOON. We’ve had ALIEN technology landed on the moon, Venus, Mars, a Comet, and I don’t know what else. We’ve actually sent a probe outside of out solar system……….. all of this is ALIEN to the worlds we visit. We are ALIENS.
Of COURSE aliens exist.