here is an idea on how to journey to Alpha Centauri, using ion engines propell the ship to near the speed of light stop at Alpha Centauri then head back again. Now of course there are some problems with that. First ion engines take a long time to speed up, now if you had nuclear engines as well as ion engines you could zoom forward with a short burst gaining a lot of speed. Now another problem is how to get enough energy, solar panels is the best option but how would you get enough energy the answer of course is a laser. The laser would have to be extremely powerful in order to reach the ship, and it would need to be orbiting the sun in a perfect alinement in order to reach the ship and, the ship would have to have spare solar panels. the laser would be inside a space station pointing at the ship well orbiting the sun .

aliens

Here are some theories about aliens and where we would find them, what solar bodies in our star system to be exact. To have life you need liquid, it doesn't have to be water, but some type of liquid. the planet also needs molecules that are capable of long mollecular chains carbon is very good for this so is silicon although the molecules are somewhat crystalline, but if the temperatures where higher it might be possible. The solar bodies that are most likely to have life are listed with an explanation of why life may exist. Europa because we think it has oceans beneath the crust and under water volcanoes that release minerals . Titan because it has lakes of methane and methane clouds (stinky*) and methane is made out of 1 carbon atom and 4 hydrogen atoms, which means long mollecular chains are possible. I also think Jupiter may have life, of course we know that Jupiter doesn't have liquid, but scientists think that many miles below all the gas there are lakes of diamond which is made out of carbon, and as we all know carbon is capable of long mollecular chains. It also makes sense because the pressure is so high, and high pressure causes the ability to move easier in higher gravity. The sun, of course there is only helium and hydrogen plasma there, but it might be possible for a conscious to form. it would be a different kind of life then the life here but still a type of life. Finally there is mars I don't think there is life there today, but judging by the geological formations water was probably present, which makes me think there was once life there. Carbon is also present and we all know what carbon is capable of. I also think it a possibility that mars seeded* earth considering it would have to have been a big disaster to knock all the water off maybe a little chunk landed on earth meaning that were Martians, so Martian fears you had better hide because we may all be Martians.

* if any one doesn't know methane is what makes farts smell so bad

* seeded means life on one planet is sent on to another planet in some way causing there to to be life on that planet too. The life would have most likely been Bacteriel because i don't think a complex organism without a spacesuit and food would survive