Do you believe in aliens?

[Trunksee]

I have never understood why people think life must be carbon based. On any planet there may be a form of life completely different than earths. If you want to base it off another human type life form, the chances are slim to none, but life will surprise everyone. I d put money on theres life out there, but maybe if the do come here they are trying to figure out the fragile carbon based life form.

[Deleted]

Somewhere in the universe, yes, odds are there are intelligent aliens. But as in UFO's floating around in Earth orbit and giving farmers rectal probes, no, afraid not.

[traen]

Well ok since we are talking about an alien life form composed of the very same "materials", aka hydrogen oxygen carbon etc etc, we then need to talk about the perfect balance our planet somehow manages to sit in.

A slight, minuscule change in the rotation or inclination of our planet would have made it impossible for life to evolve this far.
The perfect balance between the elements, of our planet's temperature make it that ONLY in a planet with EXACTLY the same characteristic as ours we can have life AS WE KNOW IT (very important)

Of course we can have different scenarios but that would be fantasizing wouldn't it.

This goes to counter everyone that says SO MANY STARS THERE MUST BE LIFE.
How many planets hit that particular balance that make life possible? That particular set of range, temperature, atmosphere and so on that would allow for life to be created as we know it?
That makes our planet not unique but certainly extremely rare.
And there the chances are already diminished greatly.


Not saying I don't believe there isnt life around the universe, I just hate people that think their way is the ONLY way.

Some people also don't understand that most of the stars they talk about are gathered close to the center of galaxy. Where any human-like life form can't exist. It took 3.5 billion years for Earth to produce humans.
Most stars that exist in the universe don't even live so long. Just in 5 billion years our own star will enter the red giant phase and the Earth will be swallowed by the Sun.
But the life on Earth will die much earlier. Just 1-2 billion years later (2 times less than it took Earth to get birth to humans) the sun radiation will become so hard that nothing would survive due to extreme temperatures.

It takes so much time to develop life, you need so precise combination of temperature, pressure, combination of elements etc etc, and the planet lifespan is so short, that makes the probability of another life existence in the universe EXTREMELY low. Even considering the amount of stars in the universe.
The chance for a sort of bacteria to appear is considerably higher. But I don't think that when people say "aliens" they mean bacteria.

Also even if some rational beings ever appeared somewhere in the universe, we would never hear about them because of the speed of light limit. Due to universe expansion we are moving further and further from other galaxies and the chance to ever meet something lowers.
The hypotetical "we think that there is life on planet X" would not be very useful if the planet X is 15 billion light years away.

[Deleted]

This is a statement which you make without proof. Ofcourse a planet needs a certain set of parameters, if you will, that allow life to flourish. However, the inclination or rotation speed is not something that will change things as much as to make life impossible. The key elements needed to make life are present in many places in the universe. We've already found traces of aminoacids on asteroids. I think the most important part for a planet is to be in the habitable zone of it's host star. This means that water should be in the same state as it is on earth, it seems water is a key part of life. The amount of planets existing in the universe is so great that there are abount to be a couple with the perfect set of parameters.


This is an important statement, because the amount of planets in the universe is so large that there are bound to be plenty that have approximately the same parameters as earth.

The last important thing to take into account is time. Life is present on this planet for a couple of billion years, bacteria etc. Intelligent life, with means to send signals into space is only very young. Let's say that we will be around for another 10 million years and then are wiped out for some reason (not a crazy assumption imo). This means that for about 10 million years other civilizations could hypotheticly detect our presence. Our signals travel with the speed of light, so in a spherical shell with thickness 10 million lightyears aliens can detect our signals, while we are still alive. The universe is ~13,5 billion years old, so it's radius is about 1000 times bigger than the radius of our signal sphere.
The chances for 2 civilizations to be able to communicate are a lot smaller than for 2 of them being present at the same time in general. The chances for 2 civilations to have existed in the universe but not at the same time is even bigger.

Do I think that alien life has existed, exists or will exist? Yes, I do.
Do I think that 2 civilizations are present at this time? I'd like to think so.
Do I think that we will ever detect a signal from another civilization? Possible
Do I think that we will communicate with them? Nah, they will have to be pretty close to our planet in order to do so.

You're absolutely right. They don't affect the presence of life itself, but they would affect life as we know it. A colder climate, less resources, less time to lose ourselves in philosophical and scientific studies, would have kept us locked in a particular stage of evolution for a long long time or maybe we wouldn't have survived who knows.
It was only marker lets say to describe the extremely fragile balance we luckily find ourselves in.
Well I don't know the exact mathematical definition of "extremely rare" but that's a statistic we could check if we could count out the planets standing in the habitable zone (there is a scientific term for it I cannot remember).

Your third point is right on the spot. We as humans occupy only an insignificant amount of time considering the life of our planet only.
The chance of us encountering an alien race in and around our state of evolution nearly outweight the massive amount of planets in the universe

Still though, I'm a dreamer and I like to "believe" we could meet someone one day. It makes me feel happy.
I guess that makes me ignorant doesn't it

[capitano666]

I have never understood why people think life must be carbon based. On any planet there may be a form of life completely different than earths. If you want to base it off another human type life form, the chances are slim to none, but life will surprise everyone. I d put money on theres life out there, but maybe if the do come here they are trying to figure out the fragile carbon based life form.

If there are indeed other life forms out there (which is already purely hypothetical) it is of course almost sure that they are completely different, (even though you may argue that some features, like the presence of eyes, would probably beneficial for them too and work in a similar way as ours).

Regarding the carbon, while it is not impossible to have life based on something else (I'm sure everyone has heard hypothesis about silicon based lifeforms) you have to take into account the fact that carbon is stunningly common in the universe because of how it is formed inside stars.

http://en.wikipedia.org/wiki/Abundan...n_the_Universe
From the table here we can see that the most commonly found atoms are, in order: Hydrogen, Helium, Oxygen, Carbon, Neon, etc... Helium and Neon are noble gases; Hydrogen, Oxygen and Carbon are the elements on which life (as we know it) is based; Hydrogen and Oxygen are the atoms that make water, in a ratio of 2 to 1...stunningly surprising that water is essential to life (as we know it), isn't it?
(water has of course other important features aside from being common and simple, like the fact that it is polar. But I digress.)

[zorkuus]

I have never understood why people think life must be carbon based.

Carbon is an element which can bond with the other common elements. Silicon can do this too but it has more restrictions on the type of enviroment a lifeform based on it could live in. For example oxygen and/or water would be deadly to silicon based life. It isn't just random chance that we happen to be carbon based life, there are good reasons for it.

[Deleted]

Well ok since we are talking about an alien life form composed of the very same "materials", aka hydrogen oxygen carbon etc etc, we then need to talk about the perfect balance our planet somehow manages to sit in.

A slight, minuscule change in the rotation or inclination of our planet would have made it impossible for life to evolve this far.
The perfect balance between the elements, of our planet's temperature make it that ONLY in a planet with EXACTLY the same characteristic as ours we can have life AS WE KNOW IT (very important)

Of course we can have different scenarios but that would be fantasizing wouldn't it.

This goes to counter everyone that says SO MANY STARS THERE MUST BE LIFE.
How many planets hit that particular balance that make life possible? That particular set of range, temperature, atmosphere and so on that would allow for life to be created as we know it?
That makes our planet not unique but certainly extremely rare.
And there the chances are already diminished greatly.


Not saying I don't believe there is life around the universe, I just hate people that think their way is the ONLY way.

Okay, I totally get you. So the point you're making is that IF it's possible there's life somewhere else in the universe, it needs to have developed life EXACTLY the same way with the same conditions as Earth did? Think about the asteroid that made the dinosaurs go extinct, think about it if that wouldn't happen. We probably wouldn't be here. So you're saying intelligent life will never develop elsewhere because the planet is not called 'Earth'? That's pretty narrow-minded tbh.

Look around you, all the diversity that has taken place what we call life. Then look into the skies. Probably no planet is the same, neither will some planet will be exactly the same as Earth. But life here on Earth proved that whatever conditions are there, life will evolve in some way to survive it. Atleast if it's not too hot and not too cold. So that's what the planet hunters are looking for atm. Just not too hot, not too cold. And ofcourse our planet is unique in it's own way because of all the specific conditions all the animals here on Earth can thrive on. But don't forget there are some other possibilities to build a planet

[Raegwyn]

as far as i know they have found bacteria and microcreatures on mars, so thats actually proof that there are aliens.
so from all planets we have reached which are 2, we have 2 with some sort of life on it. now lets add 100000000000000000000000000000000000000000000000000000000000000000000000 more planets and see if there is intelligent life on just one of them. if not that doesnt matter because the universe has much more than that small number. its mathematically impossible that there isnt intelligent life on other planets alone because of the almost infinite amount of planets.

[Deleted]

There's a higher chanse that there is a planet with life somewhere, than that there isn't, so yes.

[Raegwyn]

There's a higher chanse that there is a planet with life somewhere, than that there isn't, so yes.

exactly.
if you take an infinite number you can divide it infinite. so everyone who thinks the universe is infinite also thinks there are infinite planets that fit exactly the conditions of earth. and for real, the universe is almost infinite... how big is the chance that there arent 100000 planets that look exactly like earth with exactly same conditions?

[Deleted]

Some form of alien life (bacteria or similar) - yes probably, universe is a big place.

Multi cellular aliens (plants, animals) - no but I wouldn't be too surprised if they exist, it's possible

Intelligent aliens capable of reason and building even stone tool - no! Universe is too small and far too young for that. Maybe only if parallel realities and multiverse etc. exists.

[zorkuus]

as far as i know they have found bacteria and microcreatures on mars, so thats actually proof that there are aliens.

That isn't proof, because such an discovery hasn't happened to begin with. Where do people come up with this stuff?

the universe is almost infinite

The number 1 is as far from infinite as is a googlplex so your argument does no favors for itself.

[Deleted]

Okay, I totally get you. So the point you're making is that IF it's possible there's life somewhere else in the universe, it needs to have developed life EXACTLY the same way with the same conditions as Earth did? Think about the asteroid that made the dinosaurs go extinct, think about it if that wouldn't happen. We probably wouldn't be here. So you're saying intelligent life will never develop elsewhere because the planet is not called 'Earth'? That's pretty narrow-minded tbh.

Look around you, all the diversity that has taken place what we call life. Then look into the skies. Probably no planet is the same, neither will some planet will be exactly the same as Earth. But life here on Earth proved that whatever conditions are there, life will evolve in some way to survive it. Atleast if it's not too hot and not too cold. So that's what the planet hunters are looking for atm. Just not too hot, not too cold. And ofcourse our planet is unique in it's own way because of all the specific conditions all the animals here on Earth can thrive on. But don't forget there are some other possibilities to build a planet

That's a fair point, although mind you my post had a mocking tone mostly, directed to who was abusing statistic and scientific "evidence".

But yeah, when it comes down to out there, who's to put limits

[Woeful]

I think that the point has been made. The universe is so vast that the odds favor a huge variety of alien life forms. In fact the universe is also so vast that Carl Sagan predicted at about 10,000 worlds would be circling at the exact orbit, with the exact chemical make up to form life like Earths.

Another factor. Time: Assuming that all life forms have an extinction rate. (A rate when they die or mutate to another form),. The odds are small that an alien life form exists at the same time.

[Shinz]

That isn't proof, because such an discovery hasn't happened to begin with. Where do people come up with this stuff?


The number 1 is as far from infinite as is a googlplex so your argument does no favors for itself.

You my good sir are very very wrong, they did go to mars to fin life with the Titan rover and if you go to my post about it and Europa a few pages back you will find more info I do not care to type again. It is a controversial issue and I understand why you think they did not find life but if only microbes react in the mineral bath and it reacted with Martian soil I think they discovered life, not intelligent life but life none the less.

[s_bushido]

Some form of alien life (bacteria or similar) - yes probably, universe is a big place.

Multi cellular aliens (plants, animals) - no but I wouldn't be too surprised if they exist, it's possible

Intelligent aliens capable of reason and building even stone tool - no! Universe is too small and far too young for that. Maybe only if parallel realities and multiverse etc. exists.

Did...did you just call the universe "too small?"

[Fahrenheit]

Watch this. After viewing it, how can anyone not think that "Yeah, there has to be SOMEONE else out there"

[Maxilian]

Not really no. En what do you mean by aliens anyway? Developed like us or something else?


Pretty much this

Aliens = anything that is from another planet (or just something that´s not from earth).

[Deleted]

I do believe, however, believing the fact that something isn't proven or can't be proven is a theory not yet in practice.
So far, I believe in Extra terrestrial life-forms, as much as I believe in chance calculations.

rng is rng, right?

[Deleted]

Some form of alien life (bacteria or similar) - yes probably, universe is a big place.

Multi cellular aliens (plants, animals) - no but I wouldn't be too surprised if they exist, it's possible

Intelligent aliens capable of reason and building even stone tool - no! Universe is too small and far too young for that. Maybe only if parallel realities and multiverse etc. exists.

switch alien for life.

so from your statement I do not live in a modern apartment building built by people using all sorts of tools, from Hammers, to welding torches. I am not actual sat on my leather chair with reinforced plastic arms, legs and using my computer which has has been made using some of the most advanced tools that have been made on the planet. These parts where obviously not transferred from another part of the planet on ships, and trucks all of which where made with advanced materials.

No I am sat somewhere in a mud hut in my furs keeping myself warm by the fire which I found after the sky-gods where angry and demanded a sacrifice by making the tree at the center of my gathering explode in noise and light.



Our very existance in the current form that we are in proves beyond any shadow of a doubt that there is Intelligent Life capable of reason and building even stone tool