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Extraterrestrial Life - Does It Exist?
Life on another planet? Not a hope
In my last hub, I crunched a few numbers and came up with results even I found difficult to believe.
I wasn't trying to prove the existence of aliens, I was merely trying to establish the feasibility of whether or not life was likely to be able to survive on another planet.
My findings - although not proven - suggested that there was a big enough pool of stars in the universe - indeed in our own galaxy - that extraterrestrial life was not only possible, but highly likely.
In this hub, I'd like to evaluate the possibility that alien life on other planets really could exist, even if as some say, it's a million to one shot.
The one in a million shot
We are pretty sure there's nothing living on Mars, but that doesn't rule out anything from outside of our solar system does it?
With some ten billion stars in our own galaxy, scientists have discovered that there are more than enough to choose from that might sustain life-bearing planets, despite the fact that approximately half of the stars out there are incapable of fostering complex life such as us and the wealth of diverse life that exists on Earth.
Out of the 10 billion stars estimated to inhabit the Milky Way Galaxy, minus the 50% that are incapable, 5 billion might be. Now using the ratio of 0.006 appropriate stars out of every 5,000 stars sampled (for an explanation on this number see Anybody there?), we are left with a staggering 30,000,000,000 stars that could have planets orbiting, capable of sustaining life.
So for me, the idea that there's life out there, is not only possible, but highly probable.
The fact is, when you have so many to choose from, the likelihood of finding one that fits the bill increases, so really, it would be foolish to consider life on Earth as a fluke; a one off. It's actually more likely that it's a natural part of the life cycle of some stars.
In fact, yellow dwarf stars like our own sun, Sol, aren't even that rare either and with the discovery that some binary stars and star clusters have also the possibility of having inhabited planets whizzing round them, that further reduces the likelihood that Earth and the life on it is unique in the whole universe - even in the galaxy.
I'm sorry to burst the bubble of those who believe that Earth is a one-off, but with all those millions of stars out there that according to our scientists, are likely to have have planets in orbit around them that are perfectly capable of sustaining life, that line of reasoning is looking far less likely.
Even if life on Earth is a one in a million shot, the number of possible star systems or solar systems still remains high enough to make it mathematically probable, not just possible.
Let's prove a point.
We can for the purpose of this argument, assume that in our galaxy, there are 30,000,000,000 stars that might have planets that are capable of sustaining life. If it's a million to one shot, then that still means that 30,000 stars out there in the Milky Way have planets with life on.
More than enough I think to make the argument go from unlikely to possible wouldn't you say.
If we expand that to encompass the entire universe, that would mean that out of the 50,000,000,000,000,000,000,000,000 estimated stars that could possibly support planets with life on, finding that million to one shot would still give a totally colossal 300,000,000,000,000,000,000,000 stars with planets that support complex life, possibly similar to that on Earth.
If that's too many to envisage, let's further reduce the number there to those that may have the ability to fly through space.
At a million to one odds that still gives us 300,000,000,000,000,000 species throughout the universe who are at least on a par with us space-travel wise.
To reduce it even further, lets try and find those rarer species that have not only got the hang of blatting round in space and have got intergalactic travel down to a fine art.
That still gives us 300,000,000,000 possible.
Visitors from space. Are they still so rare?
Using the one in a million theory, I have taken the number of possible stars that could have planets that sustain life, divided that number by a million to find those that could be advanced enough like us to get into space and then divided those by a million to find the proportion of those that could possibly be indulging in intergalactic travel and still we have a possible 300,000,000,000.
And it wouldn't stop there either.
Assuming I'm even in the ball park with these numbers, that means that 300,000,000,000 star systems have ships that can travel between galaxies.
It's likely that they'd have more than one ship wouldn't it?
So just imagine how many space vessels are actually cruising round the universe as you're reading this.
I mean we're talking about numbers that are so huge, almost anything is possible - isn't it?
Now perhaps the concept of aliens visiting Earth shouldn't sound so out there. There could be millions of ships of all sorts of shapes and sizes that zip about completely unseen by us simply because the universe is so vast.
I don't think so.
A needle in a haystack
People used to think the Earth was huge and as we have mastered travel, it appears to have shrunk. There's little on the Earth's surface that's not accessible to us and most of it we can reach in a day. In fact, in some cases, even going from one country to another can be done in under a day and sometimes there and back again in under a day.
Travel for us has seemingly shrunk our globe and made it manageable.
Could it be the same in space?
Right now, the moon seems unreachable on a regular basis, but as we discover more advanced ways of powering our space crafts then greater distances will not be out of the question.
If we can crack faster than light travel, then great, but better still would be the idea of utilising the fabled wormholes. They would give us some real potential to explore the galaxy, maybe even beyond that.
It seems really simple, right?
And it is. We just haven't discovered the methods yet.
We are still very much in our infancy as far species go and it's not beyond the bounds of reason to think that there may be other species out there that are much older and much more advanced than us; species that have the technology and the know-how to be able to bridge those apparently unbridgeable gaps between us and them.
Some may argue that with the universe being so huge, how could aliens even find us? It would be like trying to find a needle in a haystack - wouldn't it?
That's a good question, but when you think of the amount of noise that we make, the dozens of satellites that orbit the globe and the amount of radio noise that must therefore be spewing from our little blue rock, we probably stand out like a beacon. Not to mention the light.
To those alien species, we must appear like one of those little 'hot hatches'; the small car with the souped-up engine and a sound system that would happily deafen a stadium. You see them all too often as they bounce down the road with a bass speaker big enough to home an entire family, thumping in the back.
Compared to us, those sophisticated aliens would be like dogs or cats with much more sensitive listening equipment that could possibly spot us from the other side of the Milky Way - even above all the noise that other stars are making.
And people are surprised that they would single us out to come and have a look?
Still not possible?
I don't think that the possibility of alien life is out of the question. In fact, I think we'd be real nunbnuts to think they didn't.
I don't necessarily think they're all going to want to come and destroy us, but it's a possibility.
There are no facts, but what does seem likely, is that there really are those from other planets, perhaps even from other galaxies that have dropped in to have a look round. There are enough reports of strange-looking lights and things in the sky that cannot be explained and whether I'm just a hopeless romantic who wants to believe, I don't know.
All I do know is that with all those stars out there, the possibilities are starting to stack up against us being alone.