Do you believe in life on other planets? (1 Viewer)

[Brad_W]

LOL

You're right about that! He had the whole, "hole in the Earth, nuclear warhead to blow up the planet" thing down pat!

 

[CharlesD]

Absolutely.

I would be surprised if we do not find evidence of some form of life elsewhere in the solar system (Mars, Europa). I have do doubt that life will be found in huge abundance throughout the universe. Complex life, life that we might recognize as "animals" or plants may well be rare, but I am equally sure such life exists out there. I would guess that there are at least 10s of planets in our galaxy right now with intelligent life on them.

Based on everything we know about our universe I think that it is only reasonable to believe in life elsewhere in the universe, and intelligent life cannot be ruled out. However based on the only life we know of (our own planet) the vast majority of life out there is probably simple unicellular life, and that not only is more complex life comparitively rare, but intelligent life even more so.

But given the size and apparent diversity of the universe, it is reasonable to beleive that there are 100,000s if not millions of Earth-like planets in our galaxy alone, and there is no reason at all to think that they do not support some kind of life.

The most unreasonable and unlikely conclusion, IMO, is that Earth alone supports life.

 

[Kenneth]

This same question was asked to an Astronomy professor at UNM when I was in high school. His response went something to this effect:
"There are two schools of thought concerning alien life ... either there is lots or we are the only ones. If our little planet is it, then that puts quite a burden on us since if we destroy our planet, then the universe would be empty. If there are lots then there is much less burden on us."
He then went on to describe our planet as kind of a galactic wilderness zone with "Danger: Immature Species - Enter at your own risk" signs outside our solar system
Personally I favor the universe is full of life theory. Even if you assume that the first generation of stars was a throwaway, because the heavier elements hadn't been created by the stars yet, the second generation of stars had a good chance to generate life and our sun is a third generation star. I doubt we would be contacted by Aliens in my lifetime because I would estimate that we would remain too dangerous to an Alien Species for many generations yet.
As to the question of whether we have the power to destroy our planet, I think it is relative. I don't think that nuclear weapons are our primary risk anymore. However, I don't think we fully understand the impact of global warming and our ability to make it worse or better. Man is like no species before us. We can exert a planetwide effect that no other species can match. Venus gives us a good example of what a runaway greenhouse effect can do. No one really knows how difficult it is to start that train rolling. Hopefully it is difficult enough that we will never find out. If we were able to initiate that level of change in our climate I don't think even the sturdiest life forms would be able to survive (but you never know).
Cheers,
Kenneth

 

[James D S]

John,
No offense taken. I realize how these conversations usually go.
Besides, the side you are argueing on is known for allowing passion into a logical debate.
Just ask Julie.
But, I'll still play along.
The problem with discussing things like this is that both sides have little proof. On the one side, here we are - the recipients of a series of events, of which, if any one were out of order or of a different duration, we would not exist. Surely, since it happened once, it could have happened again in an infinite universe (although there is little mention that even though the universe, until proven otherwise, is believed to be infinite, the amount of habitable planets most surely is not.)
Then you have the other side. All there is to go is the understanding of how life develops (albeit a series of intertwining complex theories, at best) and how improbable it would be to expect that series to recreate itself again, much less many times. They understand the significance of chance in our system.
It's a recipe for many a heated discussion born out of unrestrained passions.
I can understand wanting to believe we are not alone, otherwise, it would be a rather bleak existance being the only rock floating around in the cold of space with life.
Problem is, it doesn't make much sense to believe that for any other reason than it just makes you feel good.
I don't want us to be alone. But I doubt we aren't.
(On a side note, ealier it was mentioned that there exists life at volcanic vents in the ocean, of which, the species are capable of extreme temperatures. And it was later mentioned that there are fish in the water that are significantly biologically different in that land animals breath air. Newsflash - from the bioorganisms that inhabit that volcanic vent to the fish in the oceans to the human writing this post - they all breath oxygen ("breathing" used here to generalize the breaking down of oxygen) and are not as biologically diverse as appearances would leave you to believe. (The similarity between the DNA of a human and a gnat ranges around 95%) These are the results of what amounts to minor changes to DNA code. Right down to the little bacteria at the volcanic vent. Adapting is the easy part of all this. You're right, life will find a way. But that's obviously after the fact. You must first have life with which to adapt.)

 

[Steve Enemark]

A wise man once said (I think it was Arthur C. Clarke):
"Either we are alone in the universe, or we are not. Both possibilities are equally terrifying."

 

[James D S]

 

[Danny R]

they all breath oxygen ("breathing" used here to generalize the breaking down of oxygen) and are not as biologically diverse as appearances would leave you to believe.

As for how biologically diverse they are, I would say they certainly are different. After all, their discovery prompted a totally new Kingdom of basic life. Its hard to get any more diverse than that.

As for needing oxygen... sure they need the element oxygen somewhere in the mix... oxygen, hydrogen and carbon are present in every organic molecule that we know of. But most archaea live in anaerobic (living in the absence of free Oxygen) locations. The oxygen they use for their metabolism is bound up in nitrates and other molecules and only facilitates the chemical reactions. Still, this metabolism is totally different than that found in most other life forms.

Adapting is the easy part of all this. You're right, life will find a way. But that's obviously after the fact. You must first have life with which to adapt.

From what I've read, the archaea found in vents might be very closely related to the original life on earth rather than adapted to those conditions from what we consider "normal" bacterium. After all, the conditions where they live now (extreme environments) used to be the norm on Earth long before algae and other animals showed up.

 

[James D S]

After all, the conditions where they live now (extreme environments) used to be the norm on Earth long before algae and other animals showed up.

Right. Life will find a way after all. But we are talking about the last step in a series of events that, for this planet, must happen in the order in which they did.

The fact that there is life in extreme conditions on this earth proves nothing. We don't need proof that life can exist in extreme conditions on earth. We are not looking for proof that life can exist at high temperatures, just the plausability that the set of random events that produced the earth can repeat themselves.

We're talking about billions of years of development.

The stage where life can exist and thrive comes last.

The fact that since life on earth can exist in "extreme" environments doesn't offer any support for life on another planet. Hot, cold, wet, or dry - these conditions are immaterial. In fact, they are quite trivial.

As the bacteria thriving around volcanic vents prove.

You are putting the cart before the horse.

 

[Julie K]

Just ask Julie.

?

Explain, please.

 

[Brian Perry]

One thing seems likely: there is currently no intelligent extraterrestrial life in our immediate (~10 light years) vicinity. And if there is intelligent life farther out there, it cannot be too far ahead of us technologically. After all, we humans are limited by the current laws of physics and the speed of light. An advanced civilization would presumably be able to overcome some of those communication limitations, and send a message. Of course, maybe they are sending us messages that we just can't decipher -- kind of like us trying to communicate with ants.

I'm not denying the existence of other life -- just making the point that we are very isolated.

 

[Kevin Alexander]

I can understand wanting to believe we are not alone, otherwise, it would be a rather bleak existance being the only rock floating around in the cold of space with life.

I can understand people feeling this way as well, but would it not be bleak also to know that we share the universe w/ sparsely scattered tiny organisms incapable of any possibility of intelligence on the level of humans?

When I would look through my beginners microscope at a tiny drop of creek water from the back of my house, I never felt some "connection" to the microscopic organisms that I saw. Too me, humankind represents intelligent life - we have the desire to live, love, learn, to express emotion, we have consciousness of being - all of these qualities separate us from everything else.

To me, no one-celled organism simmering in some primordal soup next to a volcano for billions of years could ever attain to the level of humankind. For that to happen is to say that we are accidents. Scientists have painstakingly tried to duplicate the conditions that they hypothesize were present in the primordal prebiotic "soup" and then send a flash of electricity thru it in an effort to produce sugars and protein (the building blocks of all cells). These experiments produced inconclusive results. The scientist was Stanley L. Miller, and his tests are well known from the early 1950's.

 

[Artur Meinild]

I don't see why there would NOT be life on other planets than Earth.

The remaining question is just: Is it so far away that we will never know?

Guess only time will tell...

 

[Dave Poehlman]

My $.02

The human race has thought itself the center of everything since the beginning of recorded history. Man once thought the Earth was the center of the universe. Then, when he realized the Earth revolved around the Sun, he said the Sun was the center of the universe. And so on and so on.. With each discovery, man's place in the universe is made more insignificant.

I think it is rather egotistical that man would think he is the only inteligent life in the universe. As with any other aspect of science, we should assume that our existance is perfectly normal as it is the only standard (to date) that we have to base our hypothesis on.

What evidence do we have that there is life on other planets? Well, the Earth of course. We should assume that life is an inherent property of matter and that, given time, this life would progress to intelligent life.

 

[Jack Briggs]

Go all the way back to Rain's post. It's the way the question is posed in this thread's title that presents a problem. It might be better phrased, "What do you think of the evidence for life elsewhere in the Universe?"

"Belief" implies faith.

I think we all want there to be life of any sort elsewhere. No one would be happier than I if such were confirmed. But the more we know about space, and about the galactic environment, the more obstacles there appear to be for life gaining a foothold.

There was an excellent, if depressing cover story from last month's Scientific American which pretty much demonstrated that the Milky Way Galaxy is largely inhospitable to the formation of life on planets circling other stars. Forget the galactic core, with its too-intense-for-life radiation. And too far out on the galactic rim, there may be a dearth of heavy elements necessary for the formation of life-bearing terrestrial planets.

In my heart of hearts, I hope there is life elsewhere. There may even be technological sentient life--but it almost certainly won't be as abundant as the Star Trek television universe would lead you to "believe."

 

[Ryan Wright]

I doubt we would be contacted by Aliens in my lifetime because I would estimate that we would remain too dangerous to an Alien Species for many generations yet.

How would we be too dangerous for an alien species? If we're being contacted by them, then we're talking about a species who has gained interstellar travel, or has a unique method of communication. A species who, by far, would be superior to our own. The concern would not be for them - it would be for us. At this point in time, if an alien starship landed on our planet, we would be nothing to them.

 

[Kenneth]

How would we be too dangerous for an alien species? If we're being contacted by them, then we're talking about a species who has gained interstellar travel, or has a unique method of communication. A species who, by far, would be superior to our own. The concern would not be for them - it would be for us. At this point in time, if an alien starship landed on our planet, we would be nothing to them.

Technologically it is unlikely that we would pose much of a threat. However, it is likely that our fear factor of the visitors would put them in some danger if they were not constantly on guard. Biological weapons (used intentionally or unintentionally) might be devasting to them. Consider the plight of the Native Americans in North and South America who were virtually wiped out by disease when the Europeans "discovered" the New World. I would suspect that biological elements from either us or the aliens could have devasting effects on each other, unless extreme cautions were taken.

Earthlings wouldn't make attractive contact possibilities to an advanced civilization. We are still very planet centric and we would be highly suspicious of any sort of visitor, IMO. Until we turn our unified energies outwards there would be little benefit to an alien culture who contacts us. Once we turn our collective energies towards the stars then we might make a more attractive contact possibility.

Kenneth

 

[Steve Owen]

What I find interesting is that in recent years we've been discovering that that Link Removed are far more common than previously thought. We're just now discovering the methods to determine which stars have orbiting planets and the more we look, the more we find. It may take a few more (tens of) years, but we might start to get a better picture of, statistically, how many stars have planets. Based on what we've leared so far, there may be billions of planets out there.
Based on what we know about life on earth, over the course of time that the solar system has been around, we know of at least 4 places in our solar system were conditions are or could have been hospitable enough to sustain life (Venus, Earth, Mars, Europa). That would lead me to believe that of those stars with planets, there a fairly high probability that during at least some stage in their history that they could have sustained life.
The implications are staggering. Personally, I believe that the universe is filled with life. Intelligent life is probably rare and the chances of it co-existing in time with us is slim. I thought the most facinating question that came out of "Contact" was the one about getting through the age of technology. I hope that we humans can last long enough to be around for a while, but I have hard time believing that we won't do something to wipe out our species in the next couple thousand years or so (man made virus, ultra-weapons, etc.). Human intelligence has existed for an extremely short period of time when measured on the time line of biological history on this planet.
All speculation of course, but the rate at which we're finding planets gives me hope that we're not alone. I suspect that we'll have proof of life outside of earth in my lifetime.
-Steve

 

[Kevin Alexander]

Sure they do. "That's silly and completely unreasonable" is an opinion. It's not a flame. Please, don't be so quick to take offense. Being offended at every little thing is what ruins society, let alone forums like these. Personally, I think it's silly and unreasonable that you would find offense in either of these words.

Was it really necessary to bring that back up? We dropped it, so let's move on.

 

[Bob McLaughlin]

Yes, I believe there is life other planets (or moons,etc.).

To me, the question is somewhat like asking if I believe there is water on other planets. Or mountains.

In other words: if the molecular and elemental conditions are right, water will exist. Obviously, life is (likely) rarer than water, but given an entire universe and a lot of time, it had to have existed somewhere else other than Earth at some point, if not now.

Life is special, but I don't think it's unique.

 

[Jack Briggs]

Again, all this talk of belief. Presently, there is no evidence to suggest life exists offworld. We want it to exist, but wanting it and believing in it do not make good science.

There might be life elsewhere in the Universe. The indirect confirmation of planets orbiting other stars is encouraging. But the sequence of events needed for the formation of life might be exceedingly rare in the Universe. A planetary system needs to be located in the life-friendly zone of the galaxy, and it needs a so-called "good Jupiter"--i.e., a massive gas giant located far away from the system's temperate zone and able to suck away comets and asteroids from the habitable zone. Then there's the issue of a large-enough moon orbiting the potentially life-bearing planet.

One could go on and on.

As for "UFO"s--that's another topic and a can of worms at that. The "alien abduction" myth has so permeated our society that we are all "infected" with its tenets. Therefore, "hypnosis" is of little value in "recovering" suppressed "memories."

The evidence for UFOs is even less encouraging than that for intelligent life elsewhere in the Universe.