Originally Posted by Paul Markham

Yes there is life in the Universe. Odds are many types of life. For life forms to evolved along the same lines as humans and animals inhabiting Earth would need a repeat of the exact same events, chemicals, atoms, etc. The odds on that suddenly make it a far more less likely occurrence.

Atmosphere, gravity, evolution, food, land, sea, etc. on Earth may be unique to the Earth, scientists accept this. So there's a problem when an alien life form lands on Earth.

They also accept there's a problem flying life forms around our Solar system, let alone our Galaxy. Zero gravity isn't something we could cope with for long and if we did, when we landed on another planet, we would have to cope with the gravity there. Things like Space suits can't protect against gravity. Maybe a space traveler will be bouncing around in a lower gravity, or squashed lik a bug against a wind shield with a too high gravity.

Then there's the problem of getting a life form from A-B. Stop thinking in terms of getting a man on the moon and start thinking of something 100,000 times greater. Food, air, fuel, equipment, gravity, etc.

These rules not only apply to us, they apply to every living creature in the Universe. They will have evolved over millions of years for life on their planet, not for space travel or living on another planet. .