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Post by OziRiS on Jul 11, 2016 18:50:31 GMT
Sorry, of course you're likely right re: nanobots. The idea that's possibly a generation away is sending the simple bot that might build a transmitter or launcher when it reaches its destination. There's even the possibility that a nanobot network could be formed, so there would be an ever expanding cloud of communication extending from the Earth outward. And yes, power is just one of the hurdles to overcome. Building life on demand is quite a few generations away, if at all possible. Then again--there's always the possibility of a Technological Singularity outpacing our normal development, but that's real science fiction--for now. My personal opinion (based on absolutely no real data and displaying my own ignorance) is that abiogenesis in the accretion disk is a little less likely than inside the Earth's atmosphere, simply because the environment is so much more hostile. If life were possibly formed there, shouldn't we have found some evidence on Mars or the Moon as well? Instead, they appear to be sterile. In short, if extremophile life formed in the radiation/vacuum/really mean environment of the disk, what killed it off when the planets formed? From what I understand, at least one panspermia idea says it would have had to happen 13.8 billion years ago. How big was the universe then? Would that mean transmission of life was easier? As I said, it's a theory based on many different small pieces of individual evidence that have been put together to say, "Hey, this might be a possibility." We know for a fact that amino acids and other organic compounds can survive the vacuum and radiation of space, because we've found them in asteroids that have crashed into the Earth. More than any other discovery before, this was what really gave the theory of panspermia scientific traction. What we don't know is whether they formed in space, or were formed on planets and then thrown out into space by impacts during the formation of our solar system. We also know for a fact that amino acids and other organic compounds can form from nothing but pure chemistry with a little high voltage energy added. We know the chemicals and energy needed to do this exist on multiple planets and moons within our own solar system, but we also know the chemicals exist in the vacuum of space and the energy needed can be added by simple friction between particles in the accretion disk of a forming star. Life as we know it needs liquid water to form, but doesn't necessarily need liquid water to survive in a state of hibernation for prolonged periods of time (we've revived frozen bacteria that predate the dinosaurs). As a forming star heats up, water ice becomes a liquid at a certain distance and can quite possibly stay that way for millions of years, allowing simple cell structures to form inside asteroids. If those cells can survive frozen for hundreds of millions of years, those might be the ones that end up seeding planets later on. We've never encountered life that doesn't need liquid water, but we can't rule out the possibility that other liquids could be conducive to forming life as well (this is why Saturn's moon Titan is so interesting to many astrobiologists). Life might be forming in liquid methane, liquid nitrogen and so on and so forth. As for your question of why these things should be able to form in space but not survive planet formation, the simple answer would be that life is somewhat fragile. At least when it comes to severe and sudden changes in environment. If life arises in liquid water (or another liquid) in the goldilocks zone around a forming star in its early stages, most of it might be killed off the instant the infant star gets large enough for fusion to take place. At that point, the heat is turned up considerably in a very short amount of time and the location of the goldilocks zone suddenly changes by hundreds of millions of miles. Most of the liquid in the cloud evaporates and is blown further out in the disk where it condenses back into ice. Any life inside the previous goldilocks zone that relies on liquid to survive is instantly eradicated. Some asteroids that were previously in the outer part of the goldilocks zone, but now find themselves fortunately in the inner part and still have liquid may still hold life at this point, but now radiation is turned up, as well as the magnetic field of the new star. Any living thing on the surfaces of those asteroids might get killed off by that. Life inside those hunks of rock could survive, though. Whatever is left after that then has to survive planet formation, which again means heat from the impacts of asteroids slamming into the infant planets and moons thousands of times a day for millions of years. That again means liquid can't exist, so all life that depends on it and slams into these molten rocks won't survive. Once a solar system is finished forming (well, as "finished" as it can possibly be - nothing in the Universe is static) there may very well be little to no life left at all. The idea here is that life might not have as big a problem forming as we previously thought. It might form in more or less every accretion disk with the right chemicals present and those chemicals are simple and abundant throughout the Universe. In other words, the challenge for life may not be in its initial formation, but in its ability to survive and prosper in the long run. Again, all of this is just theory for now. It might turn out later on that the people behind it interpreted the evidence all wrong, but there are strong suggestions that at least some of it is right. The trick is figuring out which parts and scrapping the ones that are wrong as new evidence is found, but that's at least half the fun of doing science, isn't it?
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Post by The Urban Mythbuster on Jul 11, 2016 18:50:50 GMT
Should we change the name of this thread to 'Out of this World News'?
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Post by GTCGreg on Jul 11, 2016 18:52:17 GMT
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Post by Lokifan on Jul 11, 2016 20:45:07 GMT
Oh my yes. Great explanation. Still, showing my bias, if life was that easy to form, I'd like to think it was more resilient, given the time frames involved. Then again, we've only explored a miniscule part of our neighborhood.
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Post by The Urban Mythbuster on Jul 11, 2016 20:55:41 GMT
Oh my yes. Great explanation. Still, showing my bias, if life was that easy to form, I'd like to think it was more resilient, given the time frames involved. Then again, we've only explored a miniscule part of our neighborhood. I think this might be intended for a different comment.
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Post by OziRiS on Jul 11, 2016 21:44:10 GMT
Oh my yes. Great explanation. Still, showing my bias, if life was that easy to form, I'd like to think it was more resilient, given the time frames involved. Then again, we've only explored a miniscule part of our neighborhood. Be as biased as you like, but it's apparently a good enough theory that people who are smarter than you and I combined find it worth exploring.
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Post by Lokifan on Jul 11, 2016 23:27:38 GMT
Oh my yes. Great explanation. Still, showing my bias, if life was that easy to form, I'd like to think it was more resilient, given the time frames involved. Then again, we've only explored a miniscule part of our neighborhood. Be as biased as you like, but it's apparently a good enough theory that people who are smarter than you and I combined find it worth exploring. And I encourage such people to continue in their fine work. I also reserve the right to poke any holes in it I see, and will be thoroughly delighted when I'm found completely wrong. I am the first to admit (as I did earlier) that my opinion is basically uninformed, but I still like asking questions. Origin stories are sometimes hard to wrap one's head around. This is why I'm so excited to see the various Martian landers go poking about. I'm still hoping one will find clear cut evidence of life, thus raising even more questions. TUM: Yes, sorry; the comment was for Oz, not the guinea pigs.
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Post by silverdragon on Jul 12, 2016 6:06:03 GMT
For once, a short post.
Hey we are here, deal with it.
I have concentrated a whole two-page essay into that short term. There IS life on this planet. Other planets, if they have crossed over from the dinosaur age to maybe even small mamalian type animals, the odds of that happening without interference from their galaxy crashing into another one is major. So any planet that has life, is expected, possibly even a najority of cases of "M" type planets, but ha sit evolved into intelligent outward looking race?. We just dont know.
To find out is where science starts...
We are at the start of that, we only have a half-century of history of exploration, yet the universe is billions of years old.
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Post by OziRiS on Jul 12, 2016 10:07:09 GMT
Be as biased as you like, but it's apparently a good enough theory that people who are smarter than you and I combined find it worth exploring. And I encourage such people to continue in their fine work. I also reserve the right to poke any holes in it I see, and will be thoroughly delighted when I'm found completely wrong. I am the first to admit (as I did earlier) that my opinion is basically uninformed, but I still like asking questions. Origin stories are sometimes hard to wrap one's head around. This is why I'm so excited to see the various Martian landers go poking about. I'm still hoping one will find clear cut evidence of life, thus raising even more questions. TUM: Yes, sorry; the comment was for Oz, not the guinea pigs. Silver makes a good point that I was actually about to make myself. You asked earlier in this exchange why we haven't found evidence of life anywhere else if it forms so easily. Well, we haven't been looking for that long. We've found organic compounds spewing out of ice geysers on Saturn's moon Enceladus and there's evidence that there might be a vast liquid ocean under the crust of Jupiter's moon Europa, but that's about as far as we've gotten at this point. We haven't really actively looked for signs of life anywhere but on Mars and we haven't explored enough of that planet yet to definitively say there isn't or never has been life there. But we've found evidence of ancient oceans and there may even still be water under the surface, so that's a good sign. Same goes for Venus. There's granit on Venus. A lot of it! Granit requires liquid water to form, so we have reason to believe that early in the history of our solar system, Venus looked a lot like Earth and may even have been home to life for a while. It's not likely that we'll ever find out, because Venus is such a hostile environment today and has been for so long that any evidence of early life may be gone for good and even if it's still there, it's a difficult place to explore, but it seems the conditions were there at one point. That means there are two planets other than Earth in our own cosmic backyard that may have had life at some point in the past and at least two moons - possibly more - that may still have life on them today. But consider the effort it's taken for us to just figure out what kinds of life have lived on Earth before us. We've had to dig most of the evidence out of the ground. How much digging have we done on other worlds? It may turn out that we're both partially right. That primitive life - or at least the main ingredients to make it - can form in the accretion disk of a forming star and that it actually is resiliant enough to seed multiple planets and moons. We haven't explored nearly enough to know for sure yet, but at least we have some working theories to go off that are rooted in scientific evidence. Depending on how many resources we're willing to dedicate to exploring the possibilities of life elsewhere, the next hundred years of space exploration may become very exciting.
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Post by mrfatso on Jul 12, 2016 14:03:29 GMT
I was listening last week to a intresting episode of 'The Infinte Monkey Cage' with a professor Brian Cox, they were talking about the way the Universe and one of the points that came up from a chemist on the panel was that given our knowledge of the formation of the universe and the chemical elements that are formed in it seems inevitable that the kind of organic chemicals we find in space would form.
If you model how given a soup of Hydrogen, Helium, Carbon etc in the abundance a found in Interstellar clouds will react they will form those molecules just by the chemical reactions that would occur.
I also have to agree with OziRis finding life on other planets, or even past evidence of it is really tough, I Doubt we could find any on Venus the surface has been too heavily reworked by the conditions on it, but Mars is a good candidate. We have sent robot probes, we might find something with those but they are still quite primitive and have not spent that much time searching.Sending an ice boring or possible something to melt down through the ice on Enceladus would be an intresting possibility.
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Post by the light works on Jul 12, 2016 14:19:02 GMT
the darker side of Silver's "we're here now, deal with it" is that besides looking for life on other planets, we have sort of an obligation to make an effort to see that there's still life on our planet in a few generations.
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Post by silverdragon on Jul 13, 2016 9:31:24 GMT
"Shotgun".
A theory to be explored?.. or just the dragon "science fiction-ing" in a possible answer that may or may not fit the actual truth.
Think of the process of a scatter shot in a shotgun round, you spray out a number of pellets "in the general direction of", and hope one or two of them hit the target.
If you take a planet sized round and explode it, hand-grenade style, all the pieces fly off... If you consider our own galaxy as maybe a shotgun sized piece of that hand-grenade shot, some of the pieces landed on earth, some on all the other planets, they all maybe carried "life" that was present on that original planet sized round, some of it germinated in a "friendly" atmosphere, earth, some of it fired off on the planets closer to the sun, some of them froze their cubes off in the gas giants of the outer areas of the solar sytem, some, or most of them, flew right past, maybe even now are still travelling, in deep freeze suspended animation, until they meat another body, planet, solar system... Whats to say that hasnt happened?. It did here on earth.
We know, or have postulated, that the earth and moon were formed by a large object hitting earth some time in its galactic history. We know also that there are several deep craters in the earth that were formed by large celestial objects crashing into the earth.
We have not yet discovered which of them contained the possible "seeds" from elsewhere that created the amino acids that we suspect created life.
Thinking on, how do we know that the earth wasnt positively targeted by something shooting some kind of life-in-suspended-animation with all the possible developments in a form of code, call that code "DNA", to create an intelligent life form.
"We simply just do not know"
And that is where science begins.?...
Of course you then have to wonder how the hell the intelligent life form that targeted the solar system themselves "evolved", but that is an entirely different book, one that I didnt write yet.
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Post by silverdragon on Jul 13, 2016 9:34:24 GMT
Ditto to that.... I hope I am one of many here that agree that is the basis of becoming a member on this board, we all reserve the right to be completely wrong on anything and would be delighted to be proven such as it expands our own knowledge base.
Failure is not only an option, but the process of finding out why, is entirely welcome here.
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Post by GTCGreg on Jul 13, 2016 12:20:00 GMT
As someone, I don't know who, once said; "Failure is the first step on the road to success."
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Post by WhutScreenName on Jul 27, 2016 16:29:28 GMT
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Post by GTCGreg on Jul 27, 2016 17:57:03 GMT
I thought it wasn't PC to use the term "dwarf" anymore. It's now "the size challenged planet, Ceres"
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Post by silverdragon on Jul 28, 2016 6:52:20 GMT
How do they know what the surface is?.. it may be liquid, it may be gas, has anyone got anything on the surface makeup of ceres?..
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Post by WhutScreenName on Jul 28, 2016 13:21:39 GMT
How do they know what the surface is?.. it may be liquid, it may be gas, has anyone got anything on the surface makeup of ceres?.. All I've got is this bit from the article.
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Post by silverdragon on Jul 29, 2016 10:09:28 GMT
How do they know what the surface is?.. it may be liquid, it may be gas, has anyone got anything on the surface makeup of ceres?.. All I've got is this bit from the article. Any kind of "atmosphere", and I am guessing it may also snow a lot.... those volcano's may be making their own atmosphere slowly, and it is carrying "wind" born ice around.
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Post by mrfatso on Jul 29, 2016 16:17:41 GMT
Ceres is a carbonaceous asteroid, meaning that it is made from frozen gases like hydrogen, helium nitrogen and oxygen with other trace elements and molecules in similar abundance to the conditions in the early Solar System. It is also the only body in the asteroid belt has enough gravity to form a spherical shape, and heating in the interior due to that gravity has probably produced the energy for these cryovolcanoes.
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