Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.

sgl_imaging_challenge_celestial_motion.thumb.jpg.a9e9349c45f96ed7928eb32f1baf76ed.jpg

spurius

Life in our galaxy

Recommended Posts

I really do believe there is life out there. Given the size of our own galaxy alone, it seems very unlikely that life hasnt formed somewhere. Apparently there have been like 800 exo planets discovered, albeit confirmed to be too hostile to support life as we know it. However these planets always seem to be very close to their parent stars, and often Jupitish in nature. Given the method used for finding these planets, we are only able to observe really big planets that are really close to their stars. Such methods are nowehere near good enough to detect other solar systems like our own as the planets are too far away from the sun to block out enough of its light from the point of view of an alien 50 light years away. 

Neither do I think we will ever detect alien signals. I have heard somewhere that the signal strength from our own voyager spacecraft are billionths of a watch battery. The voyager craft are mere light hours away, never mind light years. This rules out a hell of a lot of universe for which we will likely never be able to observe in anyway. I really do think there is life out there in our own galaxy. Maybe not life forms capable of building rockets, but alien life comparable to sharks or polar bears etc.

Thats my opinion anyway.

Share this post


Link to post
Share on other sites

NO doubt about it due to the scale of the Universe. I think there may even be life on Europa. Intelligent life should also exist somewhere but no where nearly as close as within our Solar System. 

Share this post


Link to post
Share on other sites

Paul Murdin's book Are We Being Watched is a good over view. He says he set out as a believer in the probability of complex life and ended as a doubter. I'm not a doubter. I think that doubts spring, like so many things, from egocentricity. 

For me, self replicating automata (living things), seem to be driven into existence by physics, chemistry and mathematical probability. I think the unvierse will be teeming with life.

Olly

  • Like 9

Share this post


Link to post
Share on other sites

My own thoughts are that planets and life is a function of the way the universe is built and the laws that define/control it but high inteligence does seem to require an odd set of events for example here on earth the oceans have been pretty stable for many millions of years and the best example of inteligence is probably the octopus however the constant changes on land with ice ages etc produced us.

I have no doubt that the universe is full of life even in places that would seem impossible (surface of the sun) all it needs is energy and a medium to exchange molecules and any realy advanced civilisation wouldnt let something like the speed of light stop them comunicating using the quantum world.

The big thrill for me personally is when i look up at the Andromeda galaxy i have no doubts that pairs of eyes are looking back.

Alan

Edited by Alien 13
  • Like 3

Share this post


Link to post
Share on other sites

I'm with Olly.

What form that life takes doesn't really concern me. Does all intelligent life evolve to become self destructive warmongers?? 

Perhaps it me projecting my low opinion of humanity on the Universe. Perhaps we'll never know.

To be honest I'd love to visit a world that resembles the prehistoric Earth. Fertile and green, teeming with weird and wonderful species. 

Sadly I'll have to make do with watching Avatar again :)

Edited by Paul M
  • Like 1

Share this post


Link to post
Share on other sites

My problem with this is that the approach is that there a lot of stars and so there must be life - most tend to mean intelligent life also.

We are actually on an odd, very improbable planet.

The cloud mix that out system formed from had to have the right mix and proportion of elements, the sun also had to have the right make up. The sun is both relatively stable and also a single star (most seem to be doubles at least).

You would seem unable to have life bearing planets around the young white stars as in the Pleiades, too much radiation and no heavy elements. We had to come from a cloud that had the waste from a nice supernova mixed in. So the cloud must have supernova waste, meaning there had to have been a suitably local supernova. How many do we know of that are local as in 10-20 light years from us. Not a lot as in zero, so they are not that common.

Our planetary system is also stable, so far - and it is not a lot - most others systems appear to bear little resemblance to our planetary system. A slight problem to planet hunters who assumed they would all basically match our system.

The Earth has a very odd satellite around it, far, far bigger in proportion to the parent body then anything else in the solar system. And the moon formed by an improbable set of circumstances it would seem - another protoplanet of just the right size, hitting the proto earth at just the right angle and with just the right velocity to throw off debris but not quite cause the complete defragmentation of the proto Earth.

There will be other factors and the probability is a product function so goes down fast, so the probability could easily be very very low for life.

One other aspect is that eveolution on the Earth seems to have taken significant steps after each ice age. Have you seen how difficult it is to get a cycle of ice ages? It was explained on one of the TV series and believe me it was complex, very, very complex and all depended on our slightly eliptical orbit (again just right) and the precession and one other perturbation that is thrown in. Somehow with those aspects just falling right then life and we eventually arose.

That is why to me although there are a lot of stars that the occurance of life could be one in a hundred billion or less may not actually unreal I would say.

When E-ELT comes on line then more and better data will be collected and hope spectroscophy to analyse exo-planet atmospheres.

  • Like 2

Share this post


Link to post
Share on other sites

We are as much aliens as any others out there in the cosmos.

No other civilisation has ever visited earth as far as we know though, so would we ever be able to conquer interstellar travel?

Share this post


Link to post
Share on other sites

I think  "it's life Jim, but not as we know it". And I think Spock was probably right. What amazes me is why do we always assume that life WILL be as we know it - we may not even recognise it even if it was standing in front of us.

One thing is for certain the Universe/Multiverses are vast and beyond our imagination and life could be everywhere. I think a planet that produces the diverse nature that we have here cannot be alone.

Share this post


Link to post
Share on other sites

So far as interacting with intelligent alien life is concerned I think it's a vanishingly small probability.

If it exists it's not just a case of where but also when.

Our paths have to cross in time and space!

Share this post


Link to post
Share on other sites

We barely have intelligent life on this planet...

There probably is some form of life out there given the endlessness of it but we can't even communicate with any other creature on this planet with its vast supply of lifeforms (that doesn't involve a rolled-up newspaper or bribing with treats that is).

I doubt we will ever know, we'll self destruct long before we get a chance to find out.

  • Like 2

Share this post


Link to post
Share on other sites

According to Drake' s equation, the universe should be teeming with life. Never been provern,nor disproven.

Edited by LukeSkywatcher

Share this post


Link to post
Share on other sites

I have often wondered if there is a blueprint for life across the universe. As physics follows certain rules and laws I wonder if the same is true for biology. Can life only begin across the whole universe as it did on early earth (regardless of what it evolves into further down the line ) therefore making life only possible if the conditions are the same as they were on earth 3.8 billion years ago. If that is the case it must narrow down the odds of life forming somewhere quite dramatically.

Share this post


Link to post
Share on other sites

We have a problem in that we struggle to classify life on Earth that we can study as much as we want. Identifying more exotic life that may not conform to our definitions will be difficult.

Scientists still don't really agree on whether a virus is alive or not and that uses DNA / RNA much like we do.

Sent from my iPhone using Tapatalk

Share this post


Link to post
Share on other sites

One thing nature likes is diversity. Wherever there is a possibility of life, there will be.

Share this post


Link to post
Share on other sites

Ronin gives a good over view of what special circumstances created us, but that is just us. I think it dangerous to extroplate from 'life here' to 'life in general.'  For instance, we evolved at a certain rate, not a constant one but a variable rate whose history is tolerably well known to us. This produced us. Well of course it did, what would you expect it to produce? But a very different kind of evolution might occur. A very fast or a very slow rate. This would produce a different kind of life.

Some thoughts on 'intellegence.' 

1) In it's original meaning it meant 'awareness of.' But 'awareness' is a can of worms. The word cannot be separated from the being who is aware. That is us. We are aware of certain things and not others. DIfferent beings might be aware of quite different things and our awareness might not overlap with their awareness. We would, in this case, be mutually unaware of our respective intelligence.

2) We like to think that intelligence means being aware of reality, of the truth. But what we are really aware of is our perception of reality. For example, we perceive time as having a past, a moving present and a future. However, plenty of evidence from physics makes us doubt that this is the whole story. If another form of intelligence did not perceive time in this way, did not, for instance, perceive a present, then when would they talk to us?  :grin:

I said originally that our problem was egocentricity and I stand by it. We anthropomorphize. Above all, we anthropomorphize 'intelligence' which isn't surprising because it is a human word made by humans for thinking about humans*.

In debating the abundence of life in the Universe I feel the need to evoke the Copernican Principle. There will be nothing special about our position.

Olly

* Edit; and our close evolutionary cousins...

Cachou%2C%20Xmas%20Eve%20web-S.jpg

Edited by ollypenrice
  • Like 1

Share this post


Link to post
Share on other sites

I for one find it to be depressing thinking that we are alone in the universe. The thought of no other life or intelligent life is sad!

I'm still that wide eyed dreamer as I was during my youth and that's the way I will always look at it

  • Like 1

Share this post


Link to post
Share on other sites

It would be stubborn to think we not the only carbon based life form in the universe or made we should think out the box and not all life would or is carbon based

Pat

Share this post


Link to post
Share on other sites

The trouble with speculating about the existence of extraterrestrial life is we still don't know exactly how it got started here.  It was probably random chance - hundreds of millions of years of carbon-based chemicals swilling around in the water, forming, breaking, constantly creating new random patterns, until one of those random interactions stumbled across a self-replicating form.  Then evolution took care of the rest.  But we don't know how rare that random self-replicating form was.  It could have been a once-in-a-galaxy fluke.  I'd like to think it wasn't, but there's no way to know until we actually discover alien life.  Titan, Europa, and Enceladus seem good places to look.  If we find life there and confirm that it had completely independent origins (none of this panspermia stuff), then it would indicate that molecules randomly finding self-replicating forms isn't rare.

  • Like 1

Share this post


Link to post
Share on other sites

The trouble with speculating about the existence of extraterrestrial life is we still don't know exactly how it got started here.  It was probably random chance - hundreds of millions of years of carbon-based chemicals swilling around in the water, forming, breaking, constantly creating new random patterns, until one of those random interactions stumbled across a self-replicating form.  Then evolution took care of the rest.  But we don't know how rare that random self-replicating form was.  It could have been a once-in-a-galaxy fluke.  I'd like to think it wasn't, but there's no way to know until we actually discover alien life.  Titan, Europa, and Enceladus seem good places to look.  If we find life there and confirm that it had completely independent origins (none of this panspermia stuff), then it would indicate that molecules randomly finding self-replicating forms isn't rare.

That still leaves us with many millions of life forms. I personally "feel" that we probably won't find life in our solar system, but geez, thats one very small part of our galaxy, which is one very small part of the universe. Maybe universal evolution has evolved to keep lifeforms far enough apart because they can't survive together. 

All speculation of course, but it's just how I think on this subject........can'y wait to be proven wrong though. :D

Share this post


Link to post
Share on other sites

We don't even know that life first evolved on Earth, it could just as easily been seeded here by meteor impacts of debris from Mars, Venus or even on Theia. It would have been tough surviving that but some very basic forms of life have be shown to be incredibly hardy and even able to survive in space if sheltered from solar radiation. Think microbes in rocks.

Sent from my iPhone using Tapatalk

Share this post


Link to post
Share on other sites

That still leaves us with many millions of life forms. I personally "feel" that we probably won't find life in our solar system, but geez, thats one very small part of our galaxy, which is one very small part of the universe. Maybe universal evolution has evolved to keep lifeforms far enough apart because they can't survive together. 

All speculation of course, but it's just how I think on this subject........can'y wait to be proven wrong though. :D

I don't know if we'll find life in our solar system or not.  Just saying that if we do, if we find life having started independently in wildly different environments, it would give us a good deal more confidence that life is abundant in the galaxy.

  • Like 2

Share this post


Link to post
Share on other sites

I have often wondered if life could exist in a completely different timescale, we can recognise life on earth because its lifespan is comparable to our own but what if it was a few micro seconds or millions of years it wouldnt register as life to us.

Alan

Share this post


Link to post
Share on other sites

I have often wondered if life could exist in a completely different timescale, we can recognise life on earth because its lifespan is comparable to our own but what if it was a few micro seconds or millions of years it wouldnt register as life to us.

Alan

Maybe the planets are the intelligent life forms and we're just the fleas on it's back :D

  • Like 2

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.