If they are warmongering, they would probably wipe us out - since their technology would be far superior. If they were to be peaceful they may just observe us. they may even be walking among us now. I might even be one (you never know).
We won't know until we can all see them.
So...one theory is that cells came to Earth from comets or from aliens seeding the planet...the operative term is theory.
E.T. was a botanist on his home planet before he came to Earth.
Sodium chloride is formed.
It would take you apprxamently 12,740 km to get through.
No one knows.
Is there any reason to think that aliens are all cereal killers?
Uh... No.
I dont think it is likely to happen.
Aliens are more advanced then us if they came to earth but if they found out to late that the only way to kill them is to shoot them in Head then it is a fair fight.
It would get to hot. We would die.
Depends if they can cloak their ships or if they can use stealth or not. Etc etc.
If you find something that looks alien, it is more than likely going to be fake. Aliens have never landed on earth and people on started seeing UFOs and aliens in the 1950s when Sci-fi came out introuducing the possibility of aliens however all recorded alien finds have been proved as fake.
No, it is not true that Martians are aliens. The term "Martian" refers to beings or things that come from or are associated with the planet Mars. While the possibility of life existing on Mars is still being explored, there is no confirmed evidence of aliens or extraterrestrial life on Mars or any other planet.
We won't know until we can all see them.
I would hope we would try to greet them as friends until proven otherwise. The fact is that if aliens have the technology to come to earth, I don't think we would have much hope of winning a war with them.
If the earth got pulled in closer to the sun, or if the sun expands significantly, then the earth will get much warmer. That said, nothing like that is going to happen for a couple billion years yet.