Are we alone?

[trini123]

Check this out. Scientists feel we may find another earth like planet within a year. Is that a smart thing to be doing? What is the liklihood we're going to be smarter that them? Who knows this 2012 doomsday may come true afterall. We can't even get along on this one planet, what makes ppl think we'll get along across planets.



http://ca.news.yahoo.com/s/capress/1...h_like_planets

[Sirius]

Modly note: Moved to the Science & Environment board.

Personal note: Great topic. Will respond to it shortly.

[Sirius]

This is a great topic and one I have been following for some time now. We are living in some very - VERY - interesting times. This response may be a little bit on the lengthly side, but I hope some forumites take the time to read it through and lend their opinions. Surely I can't be the only space geek in here!

Up until relatively recently, the search for exoplanets (i.e. planets beyond our solar system) has resulted primarily in gas giants. Some of these gas giants have forced us to rethink planetary formation as we have found many being many times the size of Jupiter and extremely close to their stars, thereby earning the name "Hot Jupiters". This leaves us an interesting prospect: Consider the moons of our gas giants right here in the Sol system. Ice moons - most popular example being Europa. In fact, it is suspected that Europa has a liquid ocean beneath its ice sheets, heated by geothermal activity. If Jupiter were closer to the sun, these ice moons may have instead turned out to be rich with liquid water and perhaps even forests with life as we know it.

Maybe James Cameron wasn't so far off when he invented the moon of Pandora, orbiting a gas giant over at Alpha Centauri. Perhaps George Lucas wasn't so far off when inventing the forest moons of Endor and Yavin IV seen in the Star Wars films. No real surprise though; science fiction has in the past had a habit of turning out to be science fact.

Now let us make a detour from gas giants and their moons. It has only been in recent times that we have had the capacity to identify smaller worlds. We have now identified a handful of "Super Earths", that is, rocky worlds in the vicinity of 5-8 times the mass of the Earth. Interestingly enough, a handful of these are possibly capable of sustaining life! We now have more powerful telescopes. For instance, the Kepler space telescope is currently hunting for Earth-sized worlds orbiting over 100,000 of the nearest stars. By sheer statistics alone, we may well find more than a handful lying in a habitable zone - that is, the sweet spot where it is not too hot and not too cold, where liquid water may persist on the surface and give rise to life as we know it.

Now does this mean that if we find a habitable world it holds life? Well, maybe but then one has to consider whether that life evolved into complex life, and then if any of that complex life became a technological one like our own. Given that the Universe is something like 13.5 billion years old and our solar system only about 4.6 billion, then yeah...we might very well find civilizations far in advance of our own. However, within our local interstellar medium it would appear we are largely alone, or they are simply not contacting us. Why should this change?

We may be able to identify a habitable world, and through atmospheric analysis determine that life may be present, but what about beyond that? It would take an interstellar probe to pay a visit to confirm that. Currently, we are not building one so there will be some R&D time involved with such a project, not to mention scalping the billions of dollars in funding that the worlds superpowers prefer to throw behind military campaigns. The vessel, if built on nuclear pulse propulsion as proposed back in the 60's would still take 40-50 years to reach even the nearest star, and another 4 years for its findings to be received on Earth.

As it stands, there are currently 423 planets listed in the Extrasolar Planets Encyclopaedia (http://exoplanet.eu/) dated Jan 8, 2010. New worlds are turning up at such a high rate that they only ever make the news anymore if it is a particularly unusual find. We may find out within the next few months or years that there is no shortage of Earth-like planets out there. Rest assured though, the chance that we will make contact with any lifeforms living there in our lifetime is very, very slim indeed.


One more thing: Is it a smart thing to be doing? Certainly. One of the flaws of the human race is its arrogance. Perhaps what is needed to unite this planet and work towards a brighter future for all is the reality check that we are not special...that we are just another speck in the Universe surrounded by millions or billions of other like specks. That the differences amongst ourselves are meaningless in the grand scheme of things. The day we discover any evidence that life may exist elsewhere in the cosmos will be a turning point in the way we think as a civilization.

We may find actual life closer to home though. Fossilized life and present-day microbes on Mars is a distinct possibility. Complex life living in the oceans beneath Europa's ice sheets is an equally distinct possibility. The Curiosity rover launching in 2011 is tasked with the search for life on Mars. NASA is also brainstorming on constructing a melt-probe to explore Europa's oceans. We may find habitable worlds out there, but we may find life right here.

[Randall]

Where's that equation for extraterrestrial possibilites....brb i'll get it

[Randall]

Ah here it is

The Drake equation (sometimes called the "Green Bank equation", the "Green Bank Formula" or – erroneously – the "Sagan equation") is an equation to calculate the potential number of extraterrestrial civilizations in our galaxy, the Milky Way. It is used in the fields of exobiology and the search for extraterrestrial intelligence (SETI).

This equation was devised by Dr. Frank Drake (now Professor Emeritus of Astronomy and Astrophysics at the University of California, Santa Cruz) in 1960, in an attempt to estimate the number of extraterrestrial civilizations in the Milky Way with which we might come into contact.

The Drake equation states that:
where:
N = the number of civilizations in our galaxy with which communication might be possible; and
R* = the average rate of star formation per year in our galaxyfp = the fraction of those stars that have planetsne = the average number of planets that can potentially support life per star that has planetsfℓ = the fraction of the above that actually go on to develop life at some pointfi = the fraction of the above that actually go on to develop intelligent lifefc = the fraction of civilizations that develop a technology that releases detectable signs of their existence into spaceL = the length of time such civilizations release detectable signals into space.[2]


Some computations of the Drake equation, given different assumptions:
R* = 10/year, fp = 0.5, ne = 2, fl = 1, fi = 0.01, fc = 0.01, and L = 50,000 yearsN = 10 × 0.5 × 2 × 1 × 0.01 × 0.01 × 50,000 = 50 (so 50 civilizations exist in our galaxy at any given time, on average).

But a pessimist might equally well believe that life seldom becomes intelligent, and intelligent civilizations do not last very long:
R* = 10/year, fp = 0.5, ne = 2, fl = 1, fi = 0.001, fc = 0.01, and L = 500 yearsN = 10 × 0.5 × 2 × 1 × 0.001 × 0.01 × 500 = 0.05 (we are probably alone).

Alternatively, making some more optimistic assumptions, and assuming that 10% of civilizations become willing and able to communicate, and then spread through their local star systems for 100,000 years (a very short period in geologic time):
R* = 20/year, fp = 0.1, ne = 0.5, fl = 1, fi = 0.5, fc = 0.1, and L = 100,000 yearsN = 20 × 0.1 × 0.5 × 1 × 0.5 × 0.1 × 100,000 = 5,000.

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


What do i think? I think they've already found them and are now easing it into public digestion. But then i believe lots of strange things..

[trini123]

Sirius: that is a long post. Very good. Let's hope the life forms of the other planet are also not hostile. Suppose they are smarter than us and hostile? Yikes. Then again they might be friendly & easy going. Nobody knows - they might show up on Dec 21, 2012 (is that the "date"?) 122112/121221/211212

[Sirius]

Well, a reasonable expectation I think is that any alien civilization we encounter will not be all that different from us. That is, I wouldn't expect them to come bearing gifts but not looking to wage war either. I think any advanced civilization would have gone through similar trials and tribulations to us. They must have their internal differences after all, and one does not grow as a society without learning harsh lessons along the way. In similar fashion, to become a space faring civilization they must have achieved a certain level of maturity.

Science fiction is all well and good but at the end of the day, why would any civilization travel across the vast distances of space, maybe even hundreds of light years, just to wage war?

[Randall]

Well i don't think you should dismiss the possibilities of hostile actions.
Trials and tribulations aside, if they come looking for something and we're in the way...well you know. What we consider to be a hostile action may not the same to "them".


That being said, there may be many types as per the Drake equation, some being hostile and some not, you really can't tell.

But we do know that the numbers point to there being many civilizations and none at all out there.

Ahh life as a semi smart monkey, this is frustrating indeed.

Well, a reasonable expectation I think is that any alien civilization we encounter will not be all that different from us. That is, I wouldn't expect them to come bearing gifts but not looking to wage war either. I think any advanced civilization would have gone through similar trials and tribulations to us. They must have their internal differences after all, and one does not grow as a society without learning harsh lessons along the way. In similar fashion, to become a space faring civilization they must have achieved a certain level of maturity.

Science fiction is all well and good but at the end of the day, why would any civilization travel across the vast distances of space, maybe even hundreds of light years, just to wage war?

[snowbird]

Nice piece Sirius, as to ...

One more thing: Is it a smart thing to be doing? Certainly. One of the flaws of the human race is its arrogance. Perhaps what is needed to unite this planet and work towards a brighter future for all is the reality check that we are not special...that we are just another speck in the Universe surrounded by millions or billions of other like specks. That the differences amongst ourselves are meaningless in the grand scheme of things. The day we discover any evidence that life may exist elsewhere in the cosmos will be a turning point in the way we think as a civilization.

...I concur; either that, or some natural catastrophe that puts every single one of us at risk.

[sylvestter]

that equation is hurting my head....

great post sirius.

there is no way that we're alone in the universe, in my opinion anyway...

[trini123]

...
Science fiction is all well and good but at the end of the day, why would any civilization travel across the vast distances of space, maybe even hundreds of light years, just to wage war?

A civilization might do this if they have grossly abused their existing planet - depleted it resources, made the environment toxic, killed off many of its species, changed its climate by pollution.... Does any planet come to mind?


On a trip to Jamaica I saw a lake that was turned deep red by bauxite extraction by Alcan. The lake was toxic - I would never forget that. My thoughts were "My god what a mess".

[snowbird]

that equation is hurting my head....

great post sirius.

there is no way that we're alone in the universe, in my opinion anyway...

I agree with your opinion...... I mean, if we are alone......what's the point? No this thing is definitely bigger and better than all of us.

[curious55]

Here is an interesting article.... Believe it or NOT

The Greys made contact with a world governmental body for the first time in 1933 in Germany. However, they were turned away by the German government because it had already committed itself to involvement with the Giza intelligence. A renegade group of human extra terrestrials that were headquartered under the Giza plateau in Egypt. They were predominantly Pleadians. They were on their own, doing their own thing. Ashtar, Commigal, and even Jehovah were a part of the group, for some time. They came down here and played God with us. People worshipped them because they had technology which they used it as their power, big time...

to read more , here is the link.. http://www.subversiveelement.com/AliensGreysAgenda.html

[curious55]

And on the other side of the coin there are GOOD Aliens...... an article from the same website.

Edgar Cayce has said in his teachings that Arcturus is one of the most advanced civilizations in this galaxy. It is the fifth- dimensional civilization that is a prototype of Earth's future. Its energy works as an emotional, mental, and spiritual healer for humanity. It is also an energy gateway through which humans pass during death and rebirth. It functions as a way station for nonphysical consciousness to become accustomed to physicality. The Book of Knowledge: The Keys of Enoch describes it as the mid-way programming center used by the physical brotherhoods in this universe to govern the many rounds of experiments with "physicals" at this end of the galaxy.

http://www.subversiveelement.com/AliensArcturians.html

[eMJayy]

I believe that there's life everywhere in the universe. If life can exist in so much variety and with such resilience on this tiny spec of the universe, it absolutely must exist elsewhere because of the sheer size of the universe we live in. There are millions of stars in our galaxy and probably billions of galaxies out there. And on top of that, new stars and solar systems are being created everywhere in the universe every second of every day. As far as I'm concerned, our own existence is the proof that life exists elsewhere.

I don't think it's reasonable to assume that alien biology is going to be anything like ours. Based on what I've learned and observed after studying human and animal biology, the only thing we would be guaranteed to have in common with other forms of life is that our biological features would be very organized and logically linked to the environment around us. That's a consistent feature of life on earth. Other forms of life aren't guaranteed to use DNA as the means to encode their genetic structure. They may have evolved from a totally different genetic system and all their subsequent biological evolution would be influenced by this. And even if they used something like DNA, it's extremely unlikely that they'd have the exact same base pair structure (A, T, C & G) or even the same number of bases. Their cell structure would probably be vastly different from anything on earth. There's actually a huge amount of divergence when it comes to cell biochemistry here on earth, making it extremely likely that alien life will have totally different variations in their biochemistry. We like to assume that life must require oxygen because we do. Yet, when you actually look at the exact mechanism in our biochemistry that uses the oxygen we breathe, you realize that oxygen can easily be substituted. In fact, many bacteria don't use oxygen at all and, instead, utilize other electron acceptors. Our mitochondria, the part of our cells that use the oxygen we breathe, is actually a remnant of a type of bacteria that used to live in symbiosis with the eukaryotic cell. If photosynthetic organisms hadn't been pumping out oxygen into the atmosphere, we would have been breathing something else entirely, or might have evolved a system that didn't require us to breathe at all.

Intelligent life (as we define it) has only existed on this planet for perhaps a few million years (I'm being generous) out of 3.5 billion years. So if this planet was visited or observed in the past by intelligent beings from another world, they would have found no evidence of intelligent life on the planet for eons. When we eventually find life on another world, it's entirely possible that we might observe it at a time long before intelligent life actually emerges. I also think it's important to remember that intelligence has nothing to do with emotion, so we should not expect other intelligent beings to possess this human trait. And if we ever encounter any intelligent beings that don't possess emotions, we should consider them to be dangerous, because they would only be capable of acting in their own self-interest.

As far as alien visitations to earth is concerned, I do believe that there have been real UFO and 'grey' sightings, but I don't believe that alien visitation itself is the true explanation. My personal belief is that authentic UFO sightings are actually the result of time-traveling humans who are using the technology to investigate their ancestry without interfering with us. When I delved more deeply into the subject a few years back, everything seemed to logically point in that direction. It's a mistake, in my view, to make the assumption that any creature that presents itself to us must come from our period of time. And it seems illogical to me for us to assume that a creature that makes an appearance in the form of a humanoid with 2 eyes, nostrils, mouth, arms, legs and walks upright could be anything but a human being from a population of humans that have evolved many millions of years beyond us today. The probability that we would ever meet a creature that resembles us physically but isn't from earth is astronomically low. If we did, it would actually mean that the humanoid form is a necessary feature for intelligence to evolve, which is highly implausible.