I asked my dog and son for the true answers, and learned much:

1. we did not come here, we were here FIRST and forgot!

2. we are here to take care of things. (Feeding and playing with our (dog) superiors should be our highest priority!) <<oddly, the dog and kid AGREE on this!>>

3. Life is cyclic and never ending. When we go, it is back to the beginning when everything was new so we can restart the game.

The third stone from the sun
Humanoids
Out beyond the sea

Likely.

A quadrennial hit perhaps.

1. I don't know, neither does anybody else. Evolution seems like a useful working hypothesis at the moment.
2. I don't know, neither does anybody else. Seems to me the only lasting impact our lives can have is the genes we leave behind and the way we affect the lives of those we meet along the way.
3. I don't know, neither does anybody else. If I had to guess, we will be snuffed out with our sun. If we do manage to escape our solar system then we will disappear when our galaxy collides with Andromeda. Will we ever manage to go intergalactic? Pretty unlikely, but one can hope.

RE: #3 - actually when a galaxy collision is not like a car collisions, more like when two swarms of mosquitoes collide. It may be that none of the pieces actually HIT each other, but the orbits are likely to be perturbed a bit.

IF we are still around then, it should make the night sky WAY romantic!

I suspect that part of our purpose here is to figure out things like that.

On a galactic scale, even a mild orbital disturbance could be enough to send the earth crashing into the sun, so I wouldn't count on coming out of it unscathed. But yeah, it depends... we could be on the far end of the galactic disk from the collision zone when it happens.

As for the night sky... it's already WAY romantic, we just can't see it anymore because of all the light pollution. The tragedy is, most people have no idea what they're missing. Anyway, I wouldn't expect that to change too much until mankind adopts a widespread anti-light-pollution policy.

The old earth and sky will pass away; everything will be made new.

I have no origin or destination... I just am...

It doesn't have to be that way. Christ came to give abundant life.

Arcane:
My theory, as a Biochemist Catholic is: God created the Proton, Electron and Neutron. They combined creating the elements on the Periodic Table of Elements. Then science as time continued eventually chemicals merged creating organic chemicals from Earth's atmosphere and background from the time. This then created the first living organism which is believed to be one of the ancestor's of many of us and other creatures. Whether this organism went through the process of meiosis or mitosis, when it was divided I considered it the "Adam and Eve" division.

Carl Sagan says things like sex feel good because our genes are "selfish" (although he says that's not the 100% correct word) and they want to stay alive. This begs the question, do we mate for our own survival, or is the gene using us to keep itself alive? I say it's trying to keep itself alive, but like mitochondria, we have a symbiotic relationship in which case it needs us as much as we need it.

Scientists are actually currently working on this. There are a million ways that people the Earth itself will die. The sun is enlarging in order to prepare for it's dwarf stages, and in it's enlargement process it's believed to swallow the Earth. If humans don't make it by then, that's the end of the Earth and us. However there's no doubt that perhaps another planet exists which is like the Earth we live on and another similar creature has emerged that's like us. The Universe is quite large after all (and there are those who believe in Multiverses).

Firstly, our galaxy will Collide with Andromeda before our sun dies. Secondly, in the collision it is unlikely that our planet would collide with anything, or even have its orbit significantly changed. What would happen, is that clouds of gas and dust would collide, starting a massive chain of star formation, and if this occurred close enough to our beloved earth, then Earth would be bathed in lethal radiation, killing just about everything (except maybe cockroaches).
In any event, I think it is extremely optimistic to say that the Human race would survive that long. And if they did surely, they would come up with a way to survive (we're talking millions of years in the future).

In any event my answers to the questions are:

1) God created Adam and Eve, from whom all mankind is descended. I don't know how he did it, and it isn't really necessary for my salvation that I do.
2) We are mortals on earth in order to prove ourselves, and to learn and grow in ways that are only possible with a body. (I believe our spirits existed long before our bodies did).
3) I believe the world will become increasingly more wicked, and there will be many natural and man-made disasters. And then Christ will return and rule the righteous on Earth for a thousand years, after which all mankind will be judged, and I won't get into all the details.

How do you know?

Nothing's gonna change my world...

Evolution does explain how it works but it doesn't explain where it originated from and most religions can't describe who|what God really is|was but Alien theory makes sense: ancient stuff + accurate predictions that match even modern science + DNA(including Junk DNA) is just like computer program who is just waiting to be either decoded or activated. And Aliens are not perfect creators unlike God(s) so this fact alone should rise questions.
http://www.youtube.com/watch?v=5Svj4g3qgBg
If you won't search for real truth you will be left with fake truth.

But if we were created (or modified) by Aliens, this only moves the same questions to an earlier point. Where do the Aliens come from? Where they created by a supernatural being or did they evolve?