Why haven't we visited by aliens yet?

Question

I'm offering some theories, but would like to know more:
- We're the only planet with some sort of civilization
- Inhabited planets are too far apart for space travel, due to speed of light restrictions or something else
- Civilizations advanced enough to build ultrafast space ships also don't want to visit other planets (for moral reasons, or maybe they think it's too boring, or they developed an advanced cyberspace to simulate anything, including space travel)
- Civilizations across the universe evolved at about the same speed following the big bang, so other planets are still building better space ships like we do
- All civilizations that evolved to the point where they might soon build ultrafast space crafts blew themselves up with nuclear weapons etc.
- We've been visited by aliens but they (or we) keep it secret (or our memories of it will be erased after visits), or we are in fact alien descendants ourselves

Answer 1

Excellent question -- especially the details.

I would go with number 2, but I want to add a few things to it.

It is probable (but not definite) that civilizations evolve at different rates. The hominid species spent a good million years just running around like an animal before we developed the mutation that allows us to imagine the future and make decisions that are not instinctual. So, even if civilizations were to develop on many different planets, they could be seperated in TIME by a few million years easily.

On top of that, before you send out an expedition to a planet in search of life, you'd want to receive a signal from them. We've only been broadcasting into space for some 40 years now... and 40 light-years is pretty small in the grand scheme of things. Even if another civilization received our signals today, it would take them 40 years minimum to respond, barring some faster-than-light communication technology, and probably much longer to actually get here. With our current rocket technology (~40 miles/sec exiting Earth's sphere of influence), it would take us a good 4500 years just to get 1 light-year away. I think the nearest star is about 4 light years away -- so that's a long time!

Intelligent life is most likely out there somewhere (or were, or will be), but I doubt we'll run across one anytime soon. The distances and times are too great. However, unintelligent aliens (microbes, or maybe sea-creatures) we might find in the next 100-200 years on the various moons and planets in our solar system.

Answer 2

I agree with, "Civilizations across the universe evolved at about the same speed following the big bang, so other planets are still building better space ships like we do." I think this universe is far too large for us to be the only people. I hope that we can meet the others some day!

Answer 3

"Where is Everybody?" A famous question asked by Dr Fermi many years ago. It took us 3.6 billion years to develop into a thinking being. Time alone will preclude finding other beings with a higher cognitive ability. Will we find lower life forms on other planets? We,inadvertently,placed one on the moon and retrieved it during one of the moon walks.
There is a theory that alien viruses and bacteria which may be found in the upper atmosphere are responsible for some of the newer diseases. These are not cognitive creatures.
SETI is a vast waste of resources.
See the book listed below it has 50 reasons why know body has come-a-knockn.
See my blog: cosmicshootinggallery.blogspot.com there are other reasons we may never live to see another extraterrestrial species

Answer 4

Inhabited planets are simply too far apart for convenient, worthwhile travel. I'm not sure what the average distance the stars in our galaxy are spaced, but if 1 in every 1,000 stars has an inhabited planet (just a wild stab there, it's probably more like 1 in 100,000), the distance to the next planet with intelligence on it is hundreds of light years. A formidable obstacle to popping over for tea.

Answer 5

If ETs are advanced enough, they might be observing Earth right now, from a distance. If this is true, then they may have probes located at various points throughout our solar system and galaxy.

ETs aren't going to make it obvious that they are studying us because WE (human beings) might louse up their missions.

No one is sure how life got started here on planet Earth, but I'm sure if ETs had anything to do with it (via their space probes), then they have been observing us all along. We very well could be just one planet, among very many, where life has been seeded and ETs are just merely keeping record on how things are progressing on each of those planets.

Take the examples of what human beings are capable of today, through the means of technology, and imagine that in a thousand years what things we might also be able to explore from HUGE distances. Now, would this be no different than what ET is currently capable of?

Answer 6

I think that the supernatural phenomenon that we experience is partly due to US government experiments that is classified to the public. Another thing about documented experiences like "Fire from the Sky" and others like this give us pause to think maybe there are aliens out there. Why they don't make contact with us openly may be due to a fear or apprehension because as a general rule mankind from its inception (Cain v Abel) has been a violent and angry creation. I'm sure that would give any other creation a real hesitation to make contact. Another theory that I've heard is that all the "alien" stuff is demonic. This is doubt seriously, but it might be an answer in some cases.

Answer 7

I think the last one's the best answer. Not really the alien descendants, but the erasing the memory after visits one. Cause people who believe they've seen an alien or a UFO dont really keep them secrets. So I think if anyone was visited by aliens everyone would know by now...and most wouldn't believe it unless they saw it themselves.

Answer 8

We have visited Earth for centuries. Over the centuries, your planet was a curious place to visit once or twice and was not considered very interesting . Sure, your wars showed us how undeveloped you are as a species and your infantile,(in cosmic terms) dependence on god concepts does not bode well for you. We are now showing an interest in you because it is not often that we get to observe a species commit suicide. You are so close to maturing as a sentient species and it will be a shame to see you kill yourselves. There are just not enough of you becoming rational enough to force the issue. You let the least among you determine your fate, so be it.

Answer 9

We're simply too far away. And if they did come what is the probability that they would come now and not some other time out of billions of years?

They would have to be extremely close to know we are here. The probability that they are that close is near zero.

It is a long space-time journey for them. We'll have to give it time.

Answer 10

Take your p.c..: a million. they do no longer comprehend approximately our life 2. they at the instant are not to any extent further state-of-the-artwork of life than pond scum, and easily haven't any skill to even think of we exist 3. they comprehend pertaining to to the life of the image voltaic device, yet so some distance have only been waiting to discover Jupiter and Saturn and the solar 4. they damn properly comprehend that the trillions of miles are impractical to shuttle interior of their lifetimes.