Brothers and sister, I would just like to say that we need to properly define terms here. People are often mislead by the term "life" when refering to life on other planets.
For example, when scientists discuss the finding of "life" on other planets they usually refer to "microscopic lifeforms" and not mammals of large beings.
With that in mind, is it possible that life exists somewhere else in this large universe Allah created? I don't see why not. Animals? why not.
However, I don't think people can make claims about there being intelligent beings like us with "souls" and "free will" living on others planets because, Allah mentions that the Prophet PBUH is the last and final messenger sent to Al-Alameen (everything in existence).
Please explain to me how the message of islam is supposed to reach them? the prophet muhammad PBUH was the last messenger, no more after him, so how will the message reach them without a messenger?
Allah mentions in the Quran that there wasn't a nation except that Allah sent them a messenger. So how would Allah send the Prophet muhammad PBUH as a messenger to earth when... lets for argument sake there is a planet 3 billion light years away and the message of islam is supposed to reach them?
All of the logic to me says that there doesn't seem to be in any likelihood "aliens" and by aliens I mean beings like us with "free will" and "souls".
Could there be animals like elephants, birds, bees or something that looks like them or some other type of creation that we havent seen? It could be possible however, I dont think there can be beings like us, the logic speaks otherwise.