humans from space

it was reported a while that an astorid crashed into earth and all of a sunden life began, if the astorid did have are dna wud it be possible that other planets have other humans on, wot i am saying was there a planet already like earth full of humans b4 this one,

any thoughts

Well, the theory involves bacterial scale life.
It would mean life on Earth has the same origin as life on another planet... just as Humans have the same origin as Spiders, Squids and Dinosaurs.

Life "elsewhere" would evolve according to the circumstances on that world.
It would have all sorts of variety, as life on Earth has, but not necessarily similar to Earth life.

IMHO, the main weakness in Alien Sightings is that the Aliens are so similar to Humans... bigger heads or something, but still essentially Humanoid.
I don't think Alien life will mimic us so closely.
(EDIT: I'm sure Alienologists will have a good explanation for the similarity. Good for them)

[edit on 5-1-2007 by emjoi]

Originally posted by sonicX007
it was reported a while that an astorid crashed into earth

Happens all the time. You may find this article interesting. Not to mention scary as hell.

and all of a sunden life began

Well, not quite. More like all of a sudden life (or rather a lot of it) ended. You may have heard about the famous Dinosaur Killer asteroid that basically transformed planet Earth, bringing an end to the Cretaceous period and creating the conditions for mammals to become dominant among the higher animals.

But some people do believe that life originated from outer space. The theory is called panspermia. It's not very respctable. It was championed by a British Astronomer Royal, the late Sir Fred Hoyle, but he was rather keen on crackpot ideas and had pretty much disgraced himself as a scientist by the time he dropped off the perch.

if the astorid did have are dna

...it would almost certainly have vaporized and reduced to its component molecules on impact. But I suppose there's a faint chance it would survive.

wud it be possible that other planets have other humans on, wot i am saying was there a planet already like earth full of humans b4 this one?

I rather doubt it. In fact, I think there's more chance of an eight ball giving birth to a crippled archangel under water.

[edit on 5-1-2007 by Astyanax]

Originally posted by sonicX007

it was reported a while that an astorid crashed into earth and all of a sunden life began, if the astorid did have are dna wud it be possible that other planets have other humans on, wot i am saying was there a planet already like earth full of humans b4 this one,

any thoughts

I doubt we would find asteroids/meteors with DNA, however, complex organic chemicals have been found in the cosmos outside of earth. It is not impossible that complex organic compounds were seeded onto earth from elsewhere.

These basic compounds may have been the source of the materials for the first replicators that provided the basis of DNA-based life. Once evolutionary mechanisms act on the first imperfect replicators, it is unlikely that evolved life would be the same - similar in their solutions to filling niches but different (i.e. if we placed bacteria on another earth-like planet and waited 4 billion years we would see some convergence in forms but not the same species due to the random nature of mutation).

There is some preliminary evidence that the enantiomeric bias (levo-amino-acids) may have been due to cosmic properties.

So, it is one possible partial route to abiogenesis.

But as Astyanax notes, cosmic bodies also have a history of culling life on earth by invoking major extinctions events.