NASA: We'll find signs of alien life by 2025

[PWiz]

@Astudious But my entire hypothesis was based on NASA finding life in 2025. That result would confirm that life isn't a freak occurrence, and that abiogenesis is not what's rare. In any case, the coming years would certainly throw some light on whether the Great filter exists or not, and if it does, what its nature could be, such as what you have suggested about complex life evolution (as our scanning range increases). Better hold on to your ideas tightly until 2025!

 

[DennisN]

I'm getting some popcorn!
http://www.huffingtonpost.com/2015/04/08/nasa-alien-life_n_7023134.html

Interesting discussion to watch, I enjoyed it! I am also hopeful, but for some reason maybe not as hopeful as they are in the discussion, i.e. I think it may very well take longer time to find good evidence of life. But what do I know? They are professionals in this field, and I am not .

Note: I did not eat popcorn while watching it, I ate ice cream.

 

[mfb]

Just found a related article: Complex organic molecules discovered in infant star system: Hints that building blocks of chemistry of life are universal

 

[rootone]

I'm not very surprised to hear that C-N bonds can be formed naturally under conditions which might easily occur in protoplanetary nebulae.
From this it's not a great leap of imagination so speculate that given further ideal conditions, such as a watery planet, these cyanides and similar might get involved in reactions that produce some amino acids.
We know that amino acids play a significant role in the chemistry of life on Earth, but they are not self replicating molecules.
I think one of the big unknowns here is, what is the simplest self replicating molecule?, and what are there conceivable conditions in which it might naturally arise.
It sure won't be RNA, the chances of RNA spontaneously occurring seem to me unlikely in the extreme.
There has to be a precursor self producing molecule which could at least have the potential to produce a minimally functional string of RNA.

.. but then again just because RNA then DNA became the basis of Earth based life, we can't assume that is the only possible basis for it.
There could be entirely different complex self replicating chemistry arisen elsewhere, and we might not even recognise it as 'alive' until it's examined in depth,

 

[256bits]

Astro Chemistry has been studying interstellar chemicals. Finding organic molecules in the gas surrounding an infant star system was more proof confirmation of the models the scientists had/have been using.

Regarding gas-grain chemistry,

Aims.The production of saturated organic molecules in hot cores and corinos is not well understood. The standard approach is to assume that, as temperatures heat up during star formation, methanol and other species evaporate from grain surfaces and undergo a warm gas-phase chemistry at 100 K or greater to produce species such as methyl formate, dimethyl ether, and others. But a series of laboratory results shows that protonated ions, typical precursors to final products in ion-molecule schemes, tend to fragment upon dissociative recombination with electrons rather than just ejecting a hydrogen atom. Moreover, the specific proposed reaction to produce protonated methyl formate is now known not to occur at all.
Methods: .We utilize a gas-grain chemical network to probe the chemistry of the relatively ignored stage of hot core evolution during which the protostar switches on and the temperature of the surrounding gas and dust rises from 10 K to over 100 K. During this stage, surface chemistry involving heavy radicals becomes more important as surface hydrogen atoms tend to evaporate rather than react.
Results: .Our results show that complex species such as methyl formate, formic acid, and dimethyl ether can be produced in large abundance during the protostellar switch-on phase, but that both grain-surface and gas-phase processes help to produce most species. The longer the timescale for protostellar switch-on, the more important the surface processes.

http://adsabs.harvard.edu/abs/2006A&A...457..927G

Zeta Ophiuchi, runaway star from an extinct binary, heats up interstellar gas ( which can be studied ) as it plows through forming a bow.
http://apod.nasa.gov/apod/ap110204.html

 

[DennisN]

Just found a related article: Complex organic molecules discovered in infant star system: Hints that building blocks of chemistry of life are universal

I think this may deserve it's own thread, if there isn't one already (or what do you say, mfb?). I've also found the full report. But which forum does it fit in, I wonder? Edit: I guess Astronomy (Planetary Science)... I'll look for a thread, or start one, I think . Edit: I started a new thread here.

 

[Jimster41]

Sorry if it sounds like I'm shill for this guy. No agenda, I swear, though I have enjoyed his writing. I was looking for publications with his name in arxiv, found this, and thought of this thread.

http://arxiv.org/abs/1410.7374

Internalizing Null Extraterrestrial "Signals": An Astrobiological App for a Technological Society
Eric J. Chaisson
(Submitted on 27 Oct 2014)
One of the beneficial outcomes of searching for life in the Universe is that it grants greater awareness of our own problems here on Earth. Lack of contact with alien beings to date might actually comprise a null "signal" pointing humankind toward a viable future. Astrobiology has surprising practical applications to human society; within the larger cosmological context of cosmic evolution, astrobiology clarifies the energetic essence of complex systems throughout the Universe, including technological intelligence that is intimately dependent on energy and likely will be for as long as it endures. The "message" contained within the "signal" with which today's society needs to cope is reasonably this: Only solar energy can power our civilization going forward without soiling the environment with increased heat yet robustly driving the economy with increased per capita energy usage. The null "signals" from extraterrestrials also offer a rational solution to the Fermi paradox as a principle of cosmic selection likely limits galactic civilizations in time as well as in space: Those advanced life-forms anywhere in the Universe that wisely adopt, and quickly too, the energy of their parent star probably survive, and those that don't, don't.

 

[zanick]

I think its conservative to assume that there are several 1 in a million events or conditions that need to be possible. Just two of them, give odds of life happening once per solar system. three or 4 factors, make near once in our known universe. :) (not to mention trying to find it during that period that it exists as well . in 10 billion years, giving at least 4 billlion for life to form) that in itself might be more than one in million.)

 

[Snerdguy]

Life is inevitable. But detecting it many light years away in a manner that is irrefutable is far from our scientific abilities. Sure, we may find indicators such as methane and water and other chemical compounds that we associate with the existence of life. But, they can exist for other reasons. It might be safer to say that, in twenty five years, we may be able to guess with greater certainty that the conditions on a certain planet around a different star from our sun could be conducive to life. But, unless we can somehow go there and see life, it's just speculation.

The problem with detecting life anywhere is that it is fleeting. It starts at random and only lasts for a tiny fraction of the time that the universe exists. If you are looking for intelligent life, as we define it, its even more fleeting. Life starts when the conditions are appropriate and ENDS when those conditions can no longer support it. Stars and planets come and go, some form faster and others slower. But during the life of any star and it's planets, the portion of time when conditions support life is pretty narrow. Look at how many times our planet had abundant life, then lost almost all of it and then recovered only to almost loose it all again before we, the homo-sapiens became the dominant species.

Eventually, we and all life on our planet will cease to exist. But, the period of time this planet supports life is going to be very short in comparison to galactic time. So, "life" elsewhere has probably sparked and ended countless times before we even came to exist and that's why we may never encounter life outside of our solar system, let alone intelligent life. The environmental conditions and chemical reactions that bring about life happen frequently but for relatively short periods of time and space is vast. Life on our planet probably won't exist long enough and during the right period of galactic time for it to be detected by other life forms. Yes, I know. In our arrogance we think our species can go on forever. It's really just a delusion.

 

[rootone]

Sure, water, methane, amino acids, none of those are certain indicators of life.
If we were able to detect fluorocarbons, aromatic compounds, and stuff like that then some kind of life 'as we know it' might then look like the best explanation.

 

[mfb]

Life is inevitable. [...]The environmental conditions and chemical reactions that bring about life happen frequently

Please give a source for that claim.

But, the period of time this planet supports life is going to be very short in comparison to galactic time.

Life on Earth has been around for 1/3 of the age of the universe, and did not end yet. I would not call this "very short".

 

[Jimster41]

In my post 67, Chaisson, from Harvard Smithsonian Center for Astrophysics, who I believe was intimately involved with SETI - (in fact the paper referenced there was related to a talk he gave to SETI researchers) I'm pretty sure would agree that the physical conditions that drive the formation of complex biological systems are a direct result of the expansion of the universe and the 2nd Law, and as inevitable. It is the premise of much of his writing - and is outlined in the reference paper There are references in the paper that are likely relevant.

 

[Jimster41]

Here's figure from the paper, with caption:Figure 1 – Energy rate densities for a wide spectrum of systems observed throughout Nature display a clear trend across ∼14 billion years as simple primordial matter changed into increasingly intricate, complex systems. The solid black curve implies an exponential rise in system complexity as cultural evolution (steepest slope at upper right) acts faster than biological evolution (moderate slope in middle part of curve), which in turn surpasses physical evolution (smallest slope at lower left). The shaded area includes a huge ensemble of energy rate densities as many varied types of complex systems continued changing and complexifying since their origin; the several dotted black curves delineate notable evolutionary paths traversed by the major systems labeled. The energy-rate-density values and historical dates plotted here are estimates for specific systems along the evolutionary path from big bang to humankind, namely, our galaxy, star, planet, life, and society, as compiled in the bubble inserts (Chaisson 2014b). Similar graphs likely pertain to extraterrestrial life-forms, as all complex systems fundamentally hark back to the early Radiation Era, evolve throughout the Matter Era, and potentially enter the Life Era (left to right across top).

 

[mfb]

That does not look like mainstream science.

 

[Jimster41]

@mfb I'm genuinely interested that you would say that. But I'd be appreciate a more specific justification of that claim.

http://en.wikipedia.org/wiki/Eric_ChaissonIf projecting Evolution through "Society" is discomforting... I recommend this one:

https://www.amazon.com/dp/0262600692/?tag=pfamazon01-20

A link to more info about Prof Jablonka. I'm only about halfway through that one. It's quite dense. But very good.

http://en.wikipedia.org/wiki/Eva_Jablonka

 

[mfb]

@mfb I'm genuinely interested that you would say that. But I'd be interested in a more specific justification of that claim.

Which claim?
"Person A says X" means at least one person says X, but it does not make that idea mainstream.

You can make log-scale plots of everything, that does not mean there would be some deeper connection between the plotted curves. And it certainly does not mean all those curves would have to exist at all.
US funding of science correlates with deaths from hanging, strangulation and suffocation
Divorce rates are linked to margarine consumption?
Age of Miss America is linked to Murders by steam, hot vapours and hot objects?

Also, the plot is a completely arbitrary selection with questionable values. Supernovae do not fit in at all, stars are not represented accurately there, and various other objects would have curves that do not follow the plotted pattern at all.

 

[Jimster41]

Just in case you didn't drill through...

I just want to be clear. This is not mainstream...?

Eric Chaisson
From Wikipedia, the free encyclopedia

[...] (removed by mfb, see below)

 

[mfb]

Please do not copy Wikipedia articles like that, that violates copyright. I removed the 1:1 copy.
Mainstream researchers can hold views that are not shared by the majority. That does not mean those views have to be wrong, but it is good to be skeptical (and if the opinion is not mainstream, that's exactly what is happening).

 

[Jimster41]

Sorry for plagiarizing wiki.

 

[Almeisan]

Ugh, this went ugly.

Mainstream opinion is historically known to be wrong a lot of the time.
Disregarding science because it does not look 'mainstream' is wrong. Any new discovery is not going to be mainstream when it is first discovered/proposed.
Apparently that guy is a 'mainstream scientist', the work discussed is in his field, it is not like he is publishing in something he wasn't trained.
If his crazy idea is 'wrong', and most cracy ideas are, it should be pointed out in a scientific debate. Crazy ideas proposed by trained scientists putting out thorough new ideas being examined closely by peers is how science moves forward. If tomorrow everyone stopped proposing new ideas, science is dead.

And wikipedia articles are not copyrighted. All you need to do is put a link to wikipedia and indicate any changes you made.

 

[Jimster41]

Ugh, this went ugly.

Mainstream opinion is historically known to be wrong a lot of the time.
Disregarding science because it does not look 'mainstream' is wrong. Any new discovery is not going to be mainstream when it is first discovered/proposed.
Apparently that guy is a 'mainstream scientist', the work discussed is in his field, it is not like he is publishing in something he wasn't trained.
If his crazy idea is 'wrong', and most cracy ideas are, it should be pointed out in a scientific debate. Crazy ideas proposed by trained scientists putting out thorough new ideas being examined closely by peers is how science moves forward. If tomorrow everyone stopped proposing new ideas, science is dead.

I appreciate the job the moderators are trying to do. I can understand that PF has a pretty tough problem in trying to provide a stable lucid source of reference for participants, like me who are coming from all angles, bringing confusion, and being confusing. A conservative perspective is reasonable. And I'll own up to the fact I have been influenced by the writings of this guy (no-one to blame but myself). I've come to realize how much recently, largely due to conversations I've had here, and so I'm revisiting my understanding from as many angles as I can find. Frankly, I had sort of assumed his ideas were widely accepted. So I have to be open to the realization that may not be true.

That said, I like the way you put it... and so far his thinking seems particularly "right" in my travels... partly because it is so gestalt. And as I am reading his second book... I am finding it even more, interesting, and frankly, lucid. One thing I like about him, he's not afraid to ponder and talk about the squishy side of things, biology, history, society, culture etc. In other words he's a cross-disciplinarian , which is refreshing. Surely an understanding of the world must be consistent with their complex "facticity", if not explanatory.

 

[D H]

That does not look like mainstream science.

Just in case you didn't drill through...

I just want to be clear. This is not mainstream...?

Eric Chaisson
From Wikipedia, the free encyclopedia

mfb was a bit waffly in writing "That does not look like mainstream science". I'll be less waffly: That is not mainstream science.

Just because someone has a PhD does not make what they write mainstream science. Just because they get that writing published in a peer-reviewed journal does not make what they write mainstream science.

There oftentimes are large lags in science between when a concept is first introduced, then refined, and finally accepted as "mainstream". I'll use a specific example, dark matter, to illustrate. Jan Oort and Fritz Zwicky first puzzled over what appeared to be a missing mass problem in the 1930s. Vera Rubin used much better instrumentation in the 1960s and 1970s to show that there was indeed a missing mass problem. The concept of dark matter didn't become mainstream until the mid 1980s or so. A number of people have proposed various solutions regarding what dark matter actually is. While the concept of dark matter most certainly is mainstream science, not one of those proposed solutions is mainstream science.

 

[Jimster41]

I'm good with that Sir. Makes perfect sense.

Is there a policy here I may have missed regarding discussing non-mainstream science. Seriously. I didn't read all the FAQs and rules...

 

[Evo]

I'm good with that Sir. Makes perfect sense.

Is there a policy here I may have missed regarding discussing non-mainstream science. Seriously. I didn't read all the FAQs and rules...

It's at the beginning of our rules.

• We wish to discuss mainstream science.That means only topics that can be found in textbooks or that have been published in reputable journals.

https://www.physicsforums.com/threads/physics-forums-global-guidelines.414380/

 

[Jimster41]

I can imagine that the first paper which was based on a talk Chaisson gave to the founders of SETI, arguably doesn't qualify

How about this one... that describes in more detail the derivation of the plot.
https://www.cfa.harvard.edu/~ejchaisson/reprints/unifying_concept_for_astrobio.pdf

A unifying concept for astrobiology
E.J. Chaisson Wright Center, Tufts University, 4 Colby Street, Medford, MA 02155, USA e-mail : eric.chaisson@tufts.edu

Abstract: Evolution, broadly construed, has become a powerful unifying concept in much of science – not only in the biological evolution of plants and animals, but also in the physical evolution of stars and planets, and the cultural evolution of society and its many varied products. This paper (1) explores the bulk structure and functioning of open, non-equilibrium, thermodynamic systems relevant to the interdisciplinary field of astrobiology, (2) places the astrobiological landscape into an even larger, cosmological context, (3) defines life, complexity and evolution writ large, (4) claims that life depends ultimately on the expansion of the Universe and the flow of energy derived therefrom and (5) proposes a quantitative metric to characterize the rise of complexity throughout all of natural history. That metric is neither information nor negentropy, for these inveterate yet qualitative terms cannot be quantified, nor even defined, to everyone’s satisfaction in today’s scientific community. Rather, the newly proposed metric is normalized energy flow, a revision of a long-cherished term – energy – that is physically intuitive, well defined and readily measurable. All ordered systems – from rocky planets and shining stars, to buzzing bees and redwood trees – can be best judged empirically and uniformly by gauging the amount of energy acquired, stored and expressed by those systems. Appeals to anthropism are unnecessary to appreciate the impressive hierarchy of the cosmic evolutionary narrative, including a technological civilization that now embraces an energetic agenda designed to better understand, and perhaps to unify, all the natural sciences. Received 10 June 2003, accepted 24 June 2003Is the "International Journal of Astrobiology" Reputable...?

http://journals.cambridge.org/action/displayJournal?jid=IJA

 

[Evo]

The Journal has been declining since 2011, it's impact factor has dropped to 0.826.

 

[D H]

This is a bit out of order response; I want to address this first remark before I delve into the body of the discussion.

And wikipedia articles are not copyrighted. All you need to do is put a link to wikipedia and indicate any changes you made.

Wikipedia articles most certainly are copyrighted. From http://en.wikipedia.org/wiki/Wikipedia:Copyrights, "The text of Wikipedia is copyrighted (automatically, under the Berne Convention) by Wikipedia editors and contributors and is formally licensed to the public under one or several liberal licenses. "

PF doesn't comply with those licenses. For one thing, we serve ads. For another, when we find some unapproved PF mirror site, we don't approve. In fact, we strongly disapprove.

Our general response to anything that looks remotely like a copyright infringement is to apply surgery. That includes material from wikipedia.

Mainstream opinion is historically known to be wrong a lot of the time.
Disregarding science because it does not look 'mainstream' is wrong. Any new discovery is not going to be mainstream when it is first discovered/proposed.

PhysicsForums primary focus is mainstream science. That's who we are. We've tried, multiple times, to allow and even encourage speculative discussions. The general consensus was that we need a personal theory forum like we need a computer virus. See https://www.physicsforums.com/threa...y-forum-like-we-need-a-computer-virus.765736/.

There are plenty of sites on the internet that take alternate views. You are free to participate in them. You are free to participate both here and at those other sites. All we ask is that you obey our rules at our site, and don't insist we be just like those other sites.

Is there a policy here I may have missed regarding discussing non-mainstream science. Seriously. I didn't read all the FAQs and rules...

You can find the rules in a number of places. At the top right of every PF window, there's a link to "Terms and Rules" under INFO. At the bottom, you can click on ABOUT. Our ABOUT page contains a link to "Terms and Rules", and also other useful information. Finally, at the very bottom, there's a "Terms and Rules" button. We try to make it easy.
Now, back to the main subject.

I've come to realize how much recently, largely due to conversations I've had here, and so I'm revisiting my understanding from as many angles as I can find. Frankly, I had sort of assumed his ideas were widely accepted. So I have to be open to the realization that may not be true.

I would venture that very little of astrobiology has made its way to "mainstream science". Yet. There's too much extrapolating from a sample size of one from within another sample size of one. Only one of the eight planets appears to bear life, and of that life, only one species has developed the capability to escape the planet. There is so much we don't know (yet). What science does know is that what it thought it knew about planet formation 25 years ago has been turned topsy-turvy, and regarding life beyond the the, science knows that it's currently clueless. Most astrobiologists take the "we are clueless" perspective -- and they want to get out of that category.

Saying that "we'll find signs of alien life by 2025" is a bit of an aggressive claim given that cluelessness. Should they look? Absolutely. Will they find something by 2025? Who knows.

 

[mfb]

Mainstream opinion is historically known to be wrong a lot of the time.

Still much less frequent than non-mainstream options.

Disregarding science because it does not look 'mainstream' is wrong.

It is wrong if you do science. We do not do science here! We discuss science. See the forum rules.

And wikipedia articles are not copyrighted.

They are, they are published under the Creative Commons Attribution-ShareAlike 3.0 Unported License and (usually) the GNU Free Documentation License. See Wikipedia:Copyright and Wikipedia:Citing Wikipedia for details. Just adding a link to the article somewhere (which was not present) is not sufficient, and incorrect citations frequently lead to various legal issues (mainly for images).

Can we get back to the topic of extraterrestrial life?

Edit: D H was faster (and more detailed).

 

[D H]

@mfb Us being the first and only intelligent organisms to develop in the galaxy does not seem very probable either. Where are you getting at?

Doesn't seem far from speculation. I mean only one planet with intelligent life in 40 billion?

What makes you so quick to reject the null hypothesis? Everything we've seen so far (which admittedly isn't much) is consistent with the null hypothesis.

 

[PWiz]

What makes you so quick to reject the null hypothesis? Everything we've seen so far (which admittedly isn't much) is consistent with the null hypothesis.

I don't want to drag this too long, so I'll summarize it real quick.

I'm not jumping to any side. It's all "if this happens, then..." etc.
If we don't find life for a long time, the probability of abiogenesis being rare in the universe continues to grow. If we find traces of complex life which existed in the past (in the coming years), then the probability of some "Filter" existing in the universe grows (since its proves abiogenesis is common but complex life progressing to become an intergalactic species is not). If complex life still in existence is found (intelligent extraterrestrials), then the probability of other complex species existing who have not yet come into our contact grows.

Basically, we don't know how abiogenesis works, and we don't have enough evidence to comment on it right now. I'm keeping all my options open and playing in the probability playground, waiting for something to roll my way. And about the null hypothesis, I don't think our sample space is large enough as of yet to dismiss these things, so in other words, the stamp should read "No correlation observed (subject to change)."