Naked Science Forum
General Discussion & Feedback => Just Chat! => Topic started by: norcalclimber on 29/03/2010 23:51:18
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Warning: This is just for fun and to keep our imaginations fresh [:I]
What if life evolving in the Universe isn't rare? What if some unknown quantum property of the electromagnetic force actually causes life to evolve everywhere possible?
If the Universe is ~13.5 billion years old, how long before the first life showed up?
From various tests, scientists believe Earth is roughly 4.5 billion years old, and that life first appeared roughly 4.4 billion years ago.
Well that is only .1 billion years. But a star needed to form, and a whole bunch of other things, so let's just say that if life does evolve anywhere possible, that it had probably evolved by 12 billion years ago. (this is just for fun, don't get hung up on specifics please)
If life had evolved by 12 billion years ago, how long until advanced civilization evolved?
Again, let's just use Earth and say 4.5 billion years.
So perhaps advanced alien life evolved by about 7.5 billion years ago. All advanced life, would quickly realize that it is just "renting" the planet. Humans have realized it. Just like humans, aliens would have seen the need to terraform.
What is the best way to terraform as we know it?
Seed a planet with a bunch of organic carbon, amino acids, water, oxygen, etc., and basic life with photosynthetic capabilities.
The problem is, eventually, the terraformed planet may evolve advanced civilization as well.
Now this new life form needs to terraform. The new terraforming life form proceeds to terraform, and create new terraforming life forms. Pretty quickly(billions of years) the Universe would be covered with life [;D]
Could it be that the reason we are having a hard time proving abiogenesis is actually because it didn't happen on Earth?
Could myths like Noah's Ark actually have their roots in fleeing a dying planet and colonizing a new one from scratch?
Could the Hindu Vedas actually have more historical accuracy than is generally thought?
Could ancient UFO tales actually be true?
Do humans come from aliens [???] [???]
Will Gene Roddenberry be looked upon similar to Jules Verne, and we join a "Federation of Planets"?
[:o] [:o]
Sorry, got a little off track there.... but perhaps some of the "tin foil hat" theories aren't so unrealistic after all [;D]
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Isn't it thought that life began when some ' life stuff' hitched a ride on an asteroid and was planted here when it crashed ?
There is life elsewhere..I firmly believe it so (in my opinion)..there's just too many stars with too many planets out there for there to not be life.
I don't believe life elsewhere is rare..I suspect it's very common ...(in my opinion)
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You may be interested in the interview with Paul Davies in this month's Naked Astronomy podcast - http://www.thenakedscientists.com/HTML/podcasts/astronomy/show/2010.03.25/
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Isn't it thought that life began when some ' life stuff' hitched a ride on an asteroid and was planted here when it crashed ?
There is life elsewhere..I firmly believe it so (in my opinion)..there's just too many stars with too many planets out there for there to not be life.
I don't believe life elsewhere is rare..I suspect it's very common ...(in my opinion)
From what I have heard, amino acids could not have formed in early Earth's atmosphere. But I think it was in the '60s that a meteorite was found containing amino acids, and I know at some point meteorites have been discovered which contained water. From my understanding, the general consensus is that both water and amino acids arrived on Earth via meteorites.
I have also heard that DNA and RNA reaminatizes in a relatively short period of time.... so perhaps the amino acids in the meteorites is actually the remnants of DNA or RNA. I take a very Copernican view to life; I don't think life is rare, I think the Universe is probably filled with it. I suspect that there is possibly an aspect of the electromagnetic force and the unique element carbon which encourages life to develop. Perhaps carbon nanotube production is actually evidence of that force.... from what I have heard all we do is put a catalyst with the carbon and it arranges itself into highly accurate structures; seems kinda similar to life, IMHO.
But it seems to me, that if life on Earth did originate elsewhere... we have a few different possibilities as to how it came here.
1. A life sustaining planet(s) undergoes some catastrophic event which sends it hurtling through space, where eventually it crashes into Earth and seeds it with life, or the components for life.
2. Alien life decided Earth was a candidate for terraforming, and did so, adding amino acids, water, organic carbon, photosynthesizing life, etc.
3. Meteorites dropped off the water and amino acids, perhaps even basic life.... then aliens discovered it ~750 million years ago and took advantage to seed it with more complicated life (in order to stock the planet with an abundant supply of fossil fuels from the decay of large animals).
4. Alien life developed, realized they were "renting" the planet... learned that faster than light travel is impossible... decided the only way to allow life to survive was to "seed" big hunks of rock and send them hurtling through space to hopefully spawn life elsewhere. Not quite as nice an answer as actually sparing the species, but perhaps better than doing nothing but burn up as the sun goes red giant.
The interesting thing about the idea of aliens terraforming planets, and some of those developing life which then goes on to terraform planets.... is that eventually the percentage of planets with abiogenesis instead of being terraformed should be far less than the percentage with terraforming as the source of life. That seems to me to mean that it could actually be highly probable that Earth was terraformed, since we are such newcomers to the Universe.
BenV, thanks, I have the podcast downloaded and I will be sure to check it out today [:)]
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So I listened to the podcast, and I really enjoyed it a lot. Finding evidence of life evolving more than once would certainly be awesome.
But what if the conditions for abiogenesis only occurred in the early stages of our planet? What if life did evolve more than once, perhaps even dozens of times? From what I have read, the reason we believe life showed up on Earth 4.4 billion years ago is because it looks like it was covered in organic carbon by 3.8 billion years ago. What if dozens of different very basic life forms evolved and killed off each other throughout that time? Perhaps the first couple billion years of life on Earth was actually a battleground between basic life?
Or there is another possible route; maybe life did evolve more than once, but then evolved symbiotic relationships, which over time encouraged a "sharing" of genes which would make it seem as if both had a common ancestor?
It seems to me that there is a rather limited number of elements available as possible arrangements of particles. I don't see why life should be any different, so maybe we should expect all other life to be made up of the same basic components?
This subject got me thinking about how water and amino acids possibly arrived on Earth. The general thinking seems to be meteorites, but I just had a different idea.
We believe Earth is 4.5 billion years old, and the moon is too. We believe the moon was created from a dust cloud formed when a massive object slammed into Earth. Then shortly after this a bunch of water/amino acid laden meteors slammed into Earth. By 4.4 billion years we have life on Earth.
What if Earth was covered with life before the collision? What if Earth was covered in water, and life, and then a massive collision vaporized all the water...generated so much heat the land turned to molten lava? Would Earth spin at a very fast rate after a collision like that? Would Earth's iron core generate a massive magnetic field spinning so fast? Would that magnetic field keep all the vaporized water/life from blowing away in the solar wind? The "light" stuff would have been ejected farther, and would coalesce into the Moon, the denser stuff coalescing into Earth. The vaporized water would carry with it a whole bunch of carbon and amino acids, and maybe even some incredibly hardy bacteria? If any life at all survived something like that, it would have an incredible advantage with Earth starting out as a blank slate.
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It may well be possible that Earth was terraformed by aliens. I have a friend who is convinced that homo sapiens came from another planet - he points out the anomaly between ape-like human-type creatures and modern homo sapiens.
Where did we come from?
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It may well be possible that Earth was terraformed by aliens. I have a friend who is convinced that homo sapiens came from another planet - he points out the anomaly between ape-like human-type creatures and modern homo sapiens.
Where did we come from?
Definitely descended from apes, some further than others [:)] ...
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Good grief. When I saw your photo transformation I thought you had warped Dubya into Prince Charles. It was only then I read that it was intended to be an ape.
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Good grief. When I saw your photo transformation I thought you had warped Dubya into Prince Charles. It was only then I read that it was intended to be an ape.
Me too. But I didn't think it appropriate to make disparaging comments about His Royal TwitHighness.
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Chimpifying Charlie doesn't make a lot of difference ...
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http://morph.cs.st-andrews.ac.uk/
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I think that god is a spaceman. He came down and kicked life off. He then came back some time later and saw early man and that his evolution had come to a halt so he did a bit of artificial insemination and kicked it off again...read missing link. This is why the early bible stories talk about the sons of man and the sons of god.
The virgin Mary was indeed a virgin as he came down again and did a bit of artificial insemination again to put his son on earth. When he was killed, down came the space man and resuscitated him taking him off in his space ship. I think the bible says he went up on a cloud.
All this is very jolly but the question comes.....who created the spaceman?
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... god is a spaceman ... The virgin Mary was indeed a virgin as he came down again and did a bit of artificial insemination again to put his son on earth.
Ahh the De Burghian hypothesis ... [xx(]
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I bet Chris didn't do too well in his physics exams: a light year (http://en.wikipedia.org/wiki/Light_year) is a measure of distance not "time".
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He was too busy eyeing up ladies wearing clothes that are coloured in the higher wavelengths of the visual spectrum.
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Come on RD, I was expecting an answer to my last post!
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I found this thread while searching discussions for terraforming.
There are many things important about earth that make it habitable by the life that is here.
Not only that but also in just the right lifespan of our sun, and our planet core's temperature.
I have no doubt that life occurs naturally in the universe. But, if it is possible to terraform a planet, and an advanced enough civilization had overcome certain unimaginable challenges that we think may be impossible at our technological level, then it seems obvious that seeded life would be far FAR more prevalent than naturally evolved life.
Because imagine that perfect planets like earth aren't very common, and certain aspects of earth cannot be overcome with technology, like orbit distance, a perfect moon, planet size (gravity), planet type, age of its sun.
What things could be overcome? What if its possible to melt a planet, so that when it cooled it would give the planet a defensive electromagnetic field.
What if the planet didn't have enough water/carbon/iron/whatever, but other planets in the solar system did, and you could take the material from those planets and transfer them to the other planet.
Even though the process of developing a life-friendly planet may take millions of years, it still seems that terraform-developed life-sustaining planets would be much more common than naturally occurring ones, and thus earth more likely to be developed and seeded than naturally occurring.
It seems logical to develop this technology and investment effort for redundancy. We acknowledge now that life on earth could be extinguished at any moment without warning, with cosmic forces such as gamma ray bursts, and the inevitable aging of the star which limits every planet's life-sustaining capabilities. We don't even have the technology to start such an investment, yet we're already contemplating ways for how it might be possible to accomplish.