Aliens, Exist or Dont

[Green Baron]

My view on this is somewhat classical (Edit: no offense):

 

"Do aliens exist ?" is a question of belief and not sciency at all until aliens have been discovered. There is no way to define an experiment and prove the existence or non-existence of aliens(tm).

All that speculation about aliens has actually harmed real science. Some people start looking for intelligent aliens as causes for phenomena and stop to explore natural causes, including possible forms of basic life on other bodies. This is almost becoming a new form of mysticism.

 

My vote is on the third option.

 

Edited March 17, 2017 by Green Baron

[Wjolcz]

I feel like discussion about whether there are other planets with life is a bit pointless. We can't say yes and we can't say no for sure.

But if you ask my personal opinion then yes, there has to be life somewhere out there. It would be a waste of space if there isn't any. Shame any radio-operating civilization isn't closer (like 100 light years from us). Would be fun to listen to them and learn.

[kerbiloid]

16 minutes ago, Veeltch said:

Shame any radio-operating civilization isn't closer

Shame to us for still wasting energy spreading around radio waves, instead of targeted signal delivery.

Spoiler

(poll) Do aliens ex-sist?

sist - "to stop or suspend (legal proceedings)"

No, they are innocent.

 

[The Raging Sandwich]

It might be possible, but I would need to see evidence. They could be life like us, requiring the perfect conditions for them to live, or they could be like extremophiles and live in just about any condition, but we wouldn't know about them for a LONG time if they were small like the ones on Earth. 

[Wjolcz]

BTW if we're talking alien life we need to take a look at what happened on our planet. And if Snowball Earth actually somehow triggered the explosion of multicellular life then Europa and Enceladus should be prioritized, instead of Mars, when it comes to search of ETs.

[kerbiloid]

15 minutes ago, Veeltch said:

And if Snowball Earth actually somehow triggered the explosion of multicellular life then Europa and Enceladus should be prioritized, instead of Mars, when it comes to search of ETs.

Though Europa and Enceladus are snowballs, while the life explosion happened after.

[Val]

In my opinion it's extremely:

• unlikely that there's not alien life out there.
• likely that it's too far away to have ever visited earth or even be detected from earth.

[Mr. Peabody]

I know this is going to touch off a hotbed, but this whole assumption that there might be life on other planets is built on the belief that life evolved in the first place. If life evolved on earth, maybe if evolved somewhere else too. I'm not saying it didn't, because that's not scientific, but speaking scientifically evolution is a theory, not a fact. And there are a lot of problems with the theory. We can't say for sure that life evolved. It might have, who knows? But we also have to consider the possibility that life was created some other way that we haven't thought of yet. I'd need to see convincing evidence first before I conclude that there is alien life, but if there is one of Jupiter's moons is the most likely place.

[Gaarst]

1 minute ago, The Dunatian said:

I know this is going to touch off a hotbed, but this whole assumption that there might be life on other planets is built on the belief that life evolved in the first place. If life evolved on earth, maybe if evolved somewhere else too. I'm not saying it didn't, because that's not scientific, but speaking scientifically evolution is a theory, not a fact. And there are a lot of problems with the theory. We can't say for sure that life evolved. It might have, who knows? But we also have to consider the possibility that life was created some other way that we haven't thought of yet. I'd need to see convincing evidence first before I conclude that there is alien life, but if there is one of Jupiter's moons is the most likely place.

Theory does not mean hypothesis, scientifically. A theory is pretty much a fact.

[razark]

Evolution's not involved here.  We're dealing with abiogenesis.

[Mr. Peabody]

6 minutes ago, Gaarst said:

Theory does not mean hypothesis, scientifically. A theory is pretty much a fact

Definition of theory: a supposition or a system of ideas intended to explain something, especially one based on general principles independent of the thing to be explained. You cannot say scientifically that life evolved.

 

9 minutes ago, razark said:

Evolution's not involved here.  We're dealing with abiogenesis.

Definition of ambiogenesis: the original evolution of life or living organisms from inorganic or inanimate substances.

"to construct any convincing theory of abiogenesis, we must take into account the condition of the Earth about 4 billion years ago" So you see, ambiogenesis is based on the theory that life evolved.

[adsii1970]

Just now, razark said:

Evolution's not involved here.  We're dealing with abiogenesis.

How so? More complex life comes from simpler forms. bacteria with chloroplasts develop into algae, algae develops into water-based plants, and so forth. But I believe if we are going to find life in the universe we must abandon the idea that all life can only exist within the "Goldilocks zone" around stars. We must have a vision of a diversity of organisms that includes life base off other elements than carbon (₆C, ₁₂C, ₁₃C). Even sci-fi has everything looking incredibly hominid AND carbon based - except two episodes of ST-TOS, three of ST-TNG, and one in ST-V. Theoretically, there is no reason why life cannot have evolved in different environments and around different elements, such as silicon (₁₄Si) or maybe even one of the metals.  Even in the average biology class, we see the definition of "organic" is being forced to expand to include the bacterium and other life forms that have developed along deep ocean vents...

http://www.pbs.org/wgbh/aso/databank/entries/do77li.html

And since 1977, we've learned some of these actually do not "feed" off traditional food sources, but off of hydrogen sulfide ( H₂S). As our knowledge about these forms of life using alternative compounds for nutrition...

http://www.amnh.org/exhibitions/permanent-exhibitions/rose-center-for-earth-and-space/david-s.-and-ruth-l.-gottesman-hall-of-planet-earth/why-is-the-earth-habitable/life-that-lives-off-the-earth-s-energy/life-at-the-hydrothermal-vents

We must be open-minded in our search for extra-terrestrial life and must not only look for the obvious signs of an advanced or advancing civilization, but look for the simple forms, too.

[razark]

19 minutes ago, The Dunatian said:

Definition of ambiogenesis: the original evolution of life or living organisms from inorganic or inanimate substances.

By one (rather inaccurate) definition.  Abiogenesis is the arising of life from non-life.  Evolution is a process that affects life forms.

If you're talking about a scientific theory, you need to use the scientific definition of theory, not equivocation.

 

15 minutes ago, adsii1970 said:

How so? More complex life comes from simpler forms.

True.  So you follow the simpler forms backwards, and you get to the point where they crossed from weird chemistry to life forms.

[Mr. Peabody]

3 minutes ago, razark said:

Abiogenesis is the arising of life from non-life.

So basically your saying that spontaneous generation happens?

[adsii1970]

3 minutes ago, razark said:

True.  So you follow the simpler forms backwards, and you get to the point where they crossed from weird chemistry to life forms.

[Edited by adsii1970 for relevant content I want to comment on]

Exactly. To a point. My main idea is we need to look for life on the macro and micro-level. With NASA and the ESA, that's exactly how things are being done on Mars and Venus, and will eventually do it on Europa, should we ever send a lander there.

Everybody is focusing on finding our contemporary equivalent to higher organized/evolved/advanced life than ourselves. to be honest, what if (and no snickering) if we are the most advanced in our part of the galaxy? I just fear we are in such a rush to find E.T. that we forget to stop and smell the cosmic flowers, so to speak...

[razark]

Just now, adsii1970 said:

Exactly. To a point. My main idea is we need to look for life on the macro and micro-level. With NASA and the ESA, that's exactly how things are being done on Mars and Venus, and will eventually do it on Europa, should we ever send a lander there.

And should be done anywhere we ever look.  I completely agree with you on that.  Microbes are probably the most abundant type of life likely to be out there.

 

7 minutes ago, The Dunatian said:

So basically your saying that spontaneous generation happens?

Yes, I am.  But not in the outdated, disproven sense of "maggots come from rotting meat" sense.

[Green Baron]

1 hour ago, razark said:

Evolution's not involved here.  We're dealing with abiogenesis.

Oh, but yes, evolution is the process of adaptation through variation and selection and does not depend on how it started in the first place. It's a natural thing that happens as soon as conditions are right, much more than a theory, like e. g. general relativity it has proven itself correct in many ways. It is - once it has started - an inherent path to success, seen on a species level.

But it needs very much time, energy and favourable conditions, seemingly over billions of years for the development of the variety of spheres to support higher lifeforms like those on earth. Simple microbial life didn't take long to emerge on earth, just a few hundred million years after solidification of the crust. And it can have astonishingly robust forms. So, yeah, why not microbes.

But it took another >3 billion years of +/-stable conditions until the first complex biocenosis'.

We had that discussion in the Fermi thread (artificial influence on evolution is not involved here).

Applying simple probabilities is in my eyes not the correct way to address the question of higher life elsewhere due to the problem of the long time spans and stability of conditions. It all boils down to do i believe in aliens or not.

Edit: But until proven otherwise science should concentrate on natural causes for observed phenomena.

 

Edited March 17, 2017 by Green Baron

[Green Baron]

1 hour ago, The Dunatian said:

So basically your saying that spontaneous generation happens?

Traces of the origins are lost. But at some early point there must have been a transition of some sort. Not like *snip* and there they sit but the forming of the basis, self replicating chemistry if i may say so, is not as strange as one might think.

Quick search example: http://www.nature.com/nmeth/journal/v11/n5/full/nmeth.2893.html

or : http://www.nature.com/nrg/journal/v16/n1/full/nrg3841.html

Subject to debate, don't believe every word ;-)

Sorry for straying ot ...

Edited March 17, 2017 by Green Baron

[Nuke]

life is consistent with known laws of physics. if the universe has a path to entropy it will take it. life is a very good path to entropy. we do have a qualitative answer to the question 'does life exist in the universe'. still we need more data points before a quantitative answer is possible.

[Green Baron]

1 hour ago, razark said:

*snip*

Evolution is a process that affects life forms.

*snip

A, now i see your point. I would say it, in respect to the forming of life, evolution starts with self replicating chemistry. The urge and ability to adapt is built-in from the very beginning. But i am ready to accept different opinions.

[razark]

21 minutes ago, Green Baron said:

A, now i see your point. I would say it, in respect to the forming of life, evolution starts with self replicating chemistry. The urge and ability to adapt is built-in from the very beginning. But i am ready to accept different opinions.

Yes, the line between non-life self-replicating chemistry and life is probably a very fuzzy one.  Perhaps someday, we'll have the opportunity to examine it.

My distinction between abiogenesis and evolution was because this thread was concerned with "Has life begun to exist elsewhere?" and not "What form of life would exist elsewhere?".

[gogozerg]

Every time this subject shows up, igniting people's souls and beliefs, I don't know how I feel...

 

Before looking for alien life forms, we should agree on what "life" means. On Earth.

No, really, I think there's a fondamental flaw in this quest.

Are we just looking for self-reproducting objects emitting vague random signals? Definitely not people's dreams.

Or maybe "conscious" beings for other worlds, same as us or more advanced? So childish. Our own science seems to tell us that "consciousness" is a meaningless overrated phenomenom.

In a way, aliens are right here, in our courtyards. Ever talked to a tree?

 

[WinkAllKerb'']

12 hours ago, Val said:

In my opinion it's extremely:

• unlikely that there's not alien life out there.
• likely that it's too far away to have ever visited earth or even be detected from earth.

yup this +

@the same time
@not at the same place
@with the same darwin tree
@same perception/concept and tek approach

mostly & like some said too

Edited March 18, 2017 by WinkAllKerb''

[kerbiloid]

One more, and very realistic, case is always omitted.

Aliens are. They are friendly. They are conceivable. We can easily contact with them.
But they are such jerks, that we would happily miss them.

10 hours ago, razark said:

the line between non-life self-replicating chemistry and life is probably a very fuzzy one.

And probably exists in our imagination.

2 hours ago, gogozerg said:

Before looking for alien life forms, we should agree on what "life" means.

A thermodynamic self-reproducing process accumulating the (thermodynamic) information.
We really know only one kind of this enough complicated to really discuss - chemical hypercycles of carbon-based molecules.
But a set of mathematical formulas also could be treated as a life. See Daisyworld.

Edited March 18, 2017 by kerbiloid

[magnemoe]

23 hours ago, adsii1970 said:

Exactly. To a point. My main idea is we need to look for life on the macro and micro-level. With NASA and the ESA, that's exactly how things are being done on Mars and Venus, and will eventually do it on Europa, should we ever send a lander there.

Everybody is focusing on finding our contemporary equivalent to higher organized/evolved/advanced life than ourselves. to be honest, what if (and no snickering) if we are the most advanced in our part of the galaxy? I just fear we are in such a rush to find E.T. that we forget to stop and smell the cosmic flowers, so to speak...

Then we are able to search for oxygen and methane at earth sized planets we will get an good answers about how common life is