What are the teachings of the Buddha about aliens or other planets that have lives?
Is this the only place that can have life or human beings?
Is it possible to be born a Buddha in some other universe or planet?
The Buddha talked about the "world Systems" and other humans in them. This is a fascinating topic for myself as someone interested in astronomy. Here are some links speaking about world systems and related topics.
The Dhamma is sort of like the laws of mathematics and physics that govern this universe, universal to all sentient beings, everywhere. This is why we spread our metta out into the universe. I usually go one step further and spread metta out to the multi-verse.
What Buddhists Believe Venerable K. Sri Dhammananda Maha Thera: Other World Systems
http://www.budsas.org/ebud/whatbudbeliev/300.htm
The Buddhist Concept of World Bhikkhu T. Seelananda
http://bhavanasociety.org/resource/the_buddhist_concept_of_world/
The Buddha once explaining the world system said, ” Monks, as far as sun and moon revolve and illuminate all directions by their radiance, so far does the thousand-fold world system extend. And in that thousand-fold world system, there are thousand moons, a thousand suns, inhabited planets…. This thousand-fold world system is called culanikā-loka-dhātu or Minor World-System, which is the smallest unit in the universe (But all these change takes place, transformation takes place. When seeing this the instructed noble disciple is disenchanted, dispassion..)
I also find this sutta fascinating in which the Buddha appears to be speaking about a black hole..
http://www.accesstoinsight.org/tipitaka/sn/sn56/sn56.046.than.html Andhakara Sutta: Darkness
"There is, monks, an inter-cosmic[1] void, an unrestrained darkness, a pitch-black darkness, where even the light of the sun & moon — so mighty, so powerful — doesn't reach."
The traditional Mahayana cosmology allowed for multiple parallel universes, each with at most one Buddha at a time, six realms each.
In the pure land system, a pure land is like a parallel universe where you can be re-born, so yes, you can be re-born in a different world, far from Earth, in the traditional cosmology.
The various Mahayana sutras often go on at length at the great number, size, tininess and so on of the various places and inhabitants of the universe.
The story of Mahā-maudgalyāyana has a science fiction feel to it.
yes its called UTHURU KURU DIWAYINA means the land of short human beings. they were good human beings on earth. after their death they are born in that land. today we called them aliens. they are good people and do not want to harm earth. there are three other places where the human beings are.its called PURWA WEDEHA, UTHURU KURU DIWAYINA AND APARA GOYANAYA..