life beyond earth?  

evil alien conquerors is a funny cheesy movie-u should watch it for kicks.

WEll, in order for us to "attack on us and destroy earth"...they must first get here. And this is the problem with the idea of us having been visitied by alien civilizations..the limits of physics. The universe is an unimaginably big place. the nearest star to us is still over 4 light years away, and it isn't a very likely star system to develop life. It is actually a system of 3 stars orbiting ech other fairly close together, 3 rather hostile stars. It is unlikely any planet orbiting around them could develop life.
And it only gets further away from there. Lets say there is a star similar to ours, lets say close (in astronomical terms) to us. Lets say the star is a mere 50 light years away from us. Lets say somehow a civilization managed to develop over time on this planet. even if they were advanced enough to have developed mthods of travel in space that allow them to travel at .25 c or in laymen's terms, 1/4th the speed of light...it would STILL be a 200 year long trip one way for them. More than likely if there is even another civilization in our galaxy, it is probably more to the order of tens of thousands of light years away from us. It is also very likely that given the age of the galaxy, billions of years old, that a civilization may have already come and gone and we would never even have known about each other.
We will most likely find in our life time that Mars has some form of microbal life in its soil. We will prbably even find microbal life or even simple higher life in the oceans of europa. But the likely hood of uis ever encountering another civilization out there are pretty close to zero.

I've wondered the same question so many times. Unfortunately, Nobody knows for sure if there's life in other galaxies. We don't even know if there's another form of life in our own (Milky way), let alone the entire universe. The Universe is literally crammed with thousands of galaxies and it would take thousands of years to find out about that. We'd need more complex technology to figure out this Mistery.

If aliens ever visit earth, the first thing they will have to fight is the bacteria. We are able to survive because we have developed a certain kind of immunity to it. They are not equipped to deal with it. Therefore, your fears are baseless. They would annihilate themselves, if they ever step here.

I think in the future not very far away, the scientists will detect some planets with similarities to the earth, in a solar system also simliar to ours, and possible sustain life as we know it. The reason for that is because there are many solar systens identical to ours, and if that planet was liquid water, and O2 or CO2, the life could be identical to our earth, like animals, wales, fishes, ect...

Depends of the stage of evolution of that planet, we can across with other people (like similar to our past or a civilation more advance), with more or less similar to our stature or structure.
Having a life with a strange configuration with the same intelegency as we, i think is unlikely because they have to have :

- arms and legs, eyes, brain
- living in community
- doing things like houses, eat, kill animals, ect...
- If they have a tecnology society they have to build citys, having a well sustain life using the resoures of the planet.
- if they go to the space they have to have specialized worklabor - yes, if they build the so call UFOs...:)

The so call aliens that many people see i nmany places, we dont know for sure if they are real or visitors of another planet...
The UFOs that we see, are more logical they are alien probes (only cameras or computers) with no aliens on bord - because if we go tho vistit another place or planet just for studing or another reason, is more safe to send robots or androds (like the green men that many people see).

The ligths that many people see on the naked eye, have 2 origins :

- they are real aliens spacecrafs (or similar - like living things in the atmofere ?)
- They are secrets projects or other militar operations...

The two of these are happening in the world right now, for sure...thats leads to the final conclusion that are alien(s) aircrfats fying over the earth for studing, or there aren't any aliens (yet) and these are all types of our military aircraft, or spacecraft (satelites, rockets, all sortes of machines).

When you speak in terms of attack and destroy, it's clear you aren't ready to see them. Intelligence leads capability for the most part.If you are an alien culture with the great scientific ability to travel the light years to get here, what purpose would you have to destroy and attack?? They have already solved most of the problems we have today.