Defending a Rare Earth
June 21st, 2009 | Author: Oxhorn
I recently read an article that decries the “rare earth” hypothesis, which states that the idea of life outside of Earth is unlikely. I want to support the rare earth hypothesis because I think it is most likely.
The main argument used for life on other planets is that the universe is so mind-boggling huge that there must be other life out there. I find this to be a weak argument, for just because the universe is huge is no reason that life must be there. To illustrate, the average beach has millions of grains of sand. But just because there are millions of grains of sand is no reason for us to believe that one must be a diamond. In order to believe that one is a diamond, we must have evidence.
The argument that has convinced me that life outside of Earth is unlikely is the long list of conditions for life to exist:
Planet Consistency
Even though there are billions of galaxies out there, and probably millions of planets, for life as we know it to exist, we need another “rocky” planet like Earth.
Distance
A planet needs to be the right distance from its sun—any nearer or farther from the sun would make Earth too hot or cold to support life.
Magnetic Field
The Earth has an iron core that generates a magnetic “shield” that emanates from the poles and surrounds the Earth and our moon. Without this shield, the radiation from the sun would irradiate all life on Earth.
Our Moon
We have a moon that is of the exact consistency, the exact size and the exact distance from Earth to keep us from spinning off into the galactic wilderness. It affects the Earth’s rotation, stabilizes our tilt which affects seasons, and is responsible for all tidal activity, keeping our oceans from stagnating, which is very important for advanced life.
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- The planet must be “rocky”, as opposed to being a gas giant.
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- The Earth’s field protects against solar radiation.
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- The moon’s pull affects Earth’s tilt.
For life as we know it to exist elsewhere in the universe, we are looking for a planet with a moon and within a solar system consisting of a sun—all of which are exactly like Earth. Earth is one fingerprint in the universe, and no two fingerprints are the same.
Finding one planet that meets some of these qualifications is no evidence that life ever existed there. For example, it has recently been discovered that Mars once had oceans of water. Water has long since been seen as the requirement for life, but there are many more requirements that are equally important. We have not found life on Mars, despite physically going there with the Spirit and Opportunity rovers, because Mars is too far from the sun, does not have a magnetic field strong enough to protect the surface, does not have gravity strong enough to attract an atmosphere, and a host of other reasons.
I think the desire on the part of many people for life to exist outside of the Earth is so strong that it has led to bad science and “demonising” of people who hold the rare Earth hypothesis. This attitude manifests itself in arguments by calling rare-earthers “arrogant”, “ignorant” and “self-important”.
I do believe in a rare Earth, but not because I think Earth deserves life, or that my life is deserving of some special status, or that I feel like we, as a world, have earned some right to be rare and unique. I believe in a rare Earth solely because I think it is true. It is unfair to the discussion to ascribe character defects to those who believe an opposing theory.
Frankly, this is science, and science is not concerned with hopes and wishes. Science is concerned with evidence. If we ever find evidence that life exists or has existed on another planet, then great! The Earth is not rare. But until then, we can only go by the evidence we have, and we have no evidence of life outside of Earth.
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Interesting stuff oxhorn, We should be glad that our planet is perfectly positioned in every way possible.
Very interesting article, Oxhorn, but I do have a bit of an issue with it. Science isn’t just about evidence… it’s also about hypotheses, theories, ideas, and even guesses.
This argument in particular can kind of be compared to the argument of a higher power. There is no evidence for or against either fact. You cannot KNOW there is or is not a god. Lack of evidence is just a weak an argument for as against.
Certain people believe the way you believe for this or other theories. Some people believe there is life out there because that’s what makes sense to them. That’s all you can do- believe. Until it comes, you cannot prove or dissprove. You can theorize. You can believe.
I just wish more people would see things this way… less people would be like those that bash the “Rare Earth” hypothesis, and there would be less bigotry in the world. It’s an unfortunate thing…
Anyways, kudos on a very good article here. I haven’t had a good time coming up with a reply to something like this in a long time. Great work!
great info there ox! i agree that the majotiry of planets cant sustain life, but rare doesnt mean 1 of a kind. but im sure if there is life out there they may have lived in a throw away society as we do and ruined their planet.
have you looked into the ancient sumarian tablets? they tell of an advanced race that showed us “how to live” while using us to help mine gold needed to apparently fix their atmosphere.
on anoher note have you got any new machinima coming up? i love your work
Hey Oxhorn!
Me on the other side of the scale is more interested to find out if its life out there. We have found the ingredient for life on mars and looking back on our civilization its not hard to see that we did not happened accidentally.
I belive life on earth was planted here millions of years ago by an advanced race. There has been no “accidental” development of our race the last 2000 years.
Humans have gone from basic industrialization to hi-tech in under 100 years.
(Just think how our brain is programed from the start. And see other animals do the same things.)
I think its much better to have hope for inteligent life on other plantes/solar systems then to go out saying we’re the only one. Humans is not where they r today because we had no hope. We’re explorers of nature and we will find life on other worlds one day:) Or they find us.
I do not think we ever will agree on this but disagreements have always led way to larger discoveries:)
(The world is round, fusion, comedy, etc;)
Please excuse my English(and grammar;). not my main language here in Norway;) and no we do not got polar bears in the street!(Exept on Svalbard;)
And your movies kick ass! Allways laughts when watching them! Keep up the good work!
@Zero: Oh I wholeheartedly agree. The difference between hypotheses/guesses and fact, however, is that the scientist calls his guess a “guess”. In many of the articles I linked to in my own post, the authors were in abject disgust of anyone who held the rare Earth hypothesis.
Additionally, we can gauge the success of a guess based on the merits of that guess. If one guesses that there is life out there, I argue that he had better have a superior reason for that guess than simply “the universe is really big”.
@magz True, but the size of the universe does not necessitate that Earth ISN’T one of a kind, either. Seeing as how we have absolutely zero evidence for any life outside of this planet, I’m going to say that earth, as far as we know, is one of a kind.
Every ancient civilization has a creation myth about their own origin. We have no reason to believe that ancient Sumerians were visited by aliens in the same way that we have no reason to believe that the Norse gods are the offspring of maggots that crawled out of a dead giant’s armpit.
And yes, I am working on more machinima.
@gale We have found no ingredients for life on Mars. We have found evidence that water used to pool in lakes on Mars, but water is not the only ingredient for life. If it were, then any jar of distilled water would be alive.
You are free to believe in directed panspermia (that life was placed here on Earth by an advanced alien race) but that belief would be Faith, not science. There is no evidence that we have ever been visited by beings that exist outside of this planet, or that such beings even exist. The most we have is anecdotal evidence and modern interpretation of ancient stories.
Exploring is great! I hope we, as humans, get to explore all sorts of interesting things in space. I have no reason, however, to hope for any life outside of Earth. Why should I? What benefit would it be if there was life outside of Earth? It seems like an unnecessary exercise to me. If life is found outside of Earth, great. If not, great.
Hmm.
I think you’re pretty much right with your argument, but there is one thing I have to question (not necessarily to you just in general). Its that we are then assuming that all life is exactly like us and has evolved/needs the same as us.
Who is to say *this* is the only way life is formed or that life can exist. There is a lot to still figure out. I know its science fiction novel but there could be elemental ‘life’ such as found in the “Saga Of The Seven Suns” series.
There is one other factor that you have not mention and that is you are looking at humans beings are the only intelligent life out there but there may be other forms of intelligent life out there that do not require the same living condition that earth provides. Yes we don’t have proof of this but then again how would we know what to look for. On another note you make the greatest and funniest machinima out there.
sounds pretty convincing to me.
but, just because all the creatures on EARTH need to be at a right distance from te sun doesnt have to mean that other creatures cant live closer/further from te sun!
Imho your support of a rare earth theory stems from calvinistic values or some other moral and ethecal code that are form your psyche. By that, I do not imply that your arguments are invalid only that the reason you chose to support this side of the argument arent purely logical. Maybe you would like to check out the drake equation also some times refered to as the sagan equation , not that it gives any conclusive evidence just a better overview of the factors relative to this issue. There is also a documentary on the subject featuring several renowned scientists , if im not mistaken its “alien planet” or some such by discovery channel.
My objections are the following: First and foremost your “lfe as we know it ” hypothesis. Chances are that life if found is not going to have a similar genetical or even molecular structure it is also quite possible that it will not be based on carbon. Thus little green men are more or less out of the question.
My second objection is to your diamond on a beach analogy, quite simply diamonds arent formed the same way sand is thus making finding a diamond on a beach a paradox.
friendly regards from another part of our rare planet
I wouldn’t be so quick to say there is no life in universe. Scientifically, we cannot disprove it, we just do not know. It seems extremely unlikely from out point of view (just trying to find a distant planet that humanity would be able to populate is enormous task), but then again, we can’t just assume hydrocarbon & oxygen are the only way to go as last three commenters mentioned.
What I see as the biggest problem is, that even if we assume that there is a similar planet with just the same luck Earth has had, and a civilization comparable to ours, then vast size and dynamics of the universe obliterate chances of our two races finding each other to nothingness, hence making these arguments pointless. We can never prove, that Earth is rare, but that alone does not prove it isn’t: dead end.
Still… it creates rich spot for articles and discussions
– hope my English and point were both understandable, as I’m still learning.
That’s true. However, you seem to be missing the point of that maybe by some chance if there are living entities on other planets and in other galaxies, then what if they aren’t like us? What if they can handle the extreme temperatures and lack of water. Maybe they don’t need a sun. Because they are living doesn’t automatically make them built exactly like humans. They could be more or less resistant to water or heat then us. And for the Gravity, well maybe (not likely but maybe) they have found someway to get around the lack of gravity where they are, OR maybe they themselves are able to get around their no gravity problem.
@sheldon & @Miyu: The only life is life as we know it. We have no evidence for or can even imagine life existing in any other way than as it does now. To argue for life as we do not know it is akin to arguing for Blue that might be Orange. Sure, there could be life out there that does not exist as we exist, which is why I wrote the qualifier “as we know it”. But until we find evidence for such a life, or come up with a working theory for how such life could exist, we are not talking about science, but fantasy.
And in defense of my analogy, a diamond doesn’t have to have been formed on a beach. It could have been dropped there (much like directed panspermia, eh?)
@Mr42: Yes, we cannot disprove that life is not out there, until we travel to every planet that exists and physically check for life. We can, however, prove that life is not on Mars, nor on the moon, nor on any planet we have visited with a satellite or probe. All evidence we have points to the universe being devoid of life, with one sole exception–Earth. To believe that life exists outside of Earth, despite the complete lack of evidence, takes faith. And faith is not science.
I completely agree with you, but there are more factors than just the ones you stated. For one the parent star for a planetary system must be unique, you hit at this briefly but I feel there is more to be said. The planet star must be a specific type, more importantly it also must be a single star system. The reason is that the different types of stars have their own radiation levels as well as temperature levels. Now you see why it must be a single orange star, any more would create too much radiation and temperature for any planet orbiting close enough to support life.
I do disagree with your statement about faith not being science. Mostly because my stand on science is that it requires more faith than any other religion. There are scientists who believe that there are miniature black holes all around us and because they devour all light, we cannot see them. They have no proof of their existence yet they staunchly defend their beliefs. The same is with dark energy, the only proof that can be found is an unknown force that is acting on the galaxies and other astronomical phenomenon. What is preposterous is their inability to accept that there may be a completely reasonable explanation for anything that happens in the universe. Instead they cling to their archaic theories and stretch them to unbelievable proportions to make them fit.
You know how when you play a video game and the outside of a dungeon looks much smaller on the outside in relation to what is on the inside? From a lore perspective the only true answer is that is must have been a wizard that did it. The same could be said with the universe, you could attempt to believe a string of very thin theories that resemble a fishing net more than a reasonable explanation for the creation of the universe. Or you could resign to accept that there must be a greater power that created all that we see, essentially just say “God must have done it”. Because in the end with everything that must fall into place for their to be life on a planet, it was either God who did it or one very improbable occurrence that is unlikely to repeat itself.