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tv   World Stories  Deutsche Welle  February 20, 2021 8:15pm-8:30pm CET

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kremlin critic i like say the valley faced 2 separate court verdicts and last go 1st one court dismissed his appeal against a jail sentence for breaking provisions by traveling to germany then he was found guilty of defamation in a different case. you're watching the news live from berlin that remember you can always get more information on our web site. on our spicer actually which. country. and how many push. us turn out in the morning climate change isn't often stores places one place to wait for just one week. before it can really get. we still have time to ask i'm going. to. say.
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if we just take the time to observe that nature provides us with a fascinating spectacle. he's the planet of life running crawling all flying life abounds everywhere. but for all this beautiful diversity to have proliferated earth has had to provide a favorable environment for around 4000000000 years. leading. then with the conditions which enabled the blooming of life on earth and could these conditions be present elsewhere resulting in alternative ecosystems.
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in an attempt to answer these questions scientists who scour the cosmos for signs of life. they've built giant telescopes with which to probe the universe and listen to the whispering of the stars but space has remained resolutely silent and. scientists have sent probes to the very edges of our solar system but all they've sent back has been images of planets inimical to life over the last 25 years however astronomers have discovered thousands of incredibly diverse planets in our galaxy alone. so many strange worlds with no sign of life not one other planet similar to our own so could it be that earth really is unique.
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all living things on earth are made of the same building blocks long carbon based molecules scientists now think that a large proportion of these molecules came from outside planet earth. comets and asteroids could be the missing links of a long chain the chain began with the simple molecules found in the early cloud dusts and culminated with the building blocks of life from which life on earth 1st sprang the chain leading to life. may let me check out when it all but this carbonaceous material that ended up going to earth oceans that adventure all whole series of changes of particular temperatures particular events a particular star very particular radiation that. our own son the to hear.
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this organic matter was constantly altered on its long journey towards our planet its final composition the product of a singular history which scientists are now attempting to reconstruct. to understand what happened to these comments during their transformation and journey through the solar system louis don't decoy and click why don't they have
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taken an original approach which doesn't require long and costly interplanetary travel more a trip in a test tube. or just a joy there's the idea of a journey which is quite poetic but it's framed in a very scientific context sure paroles trying to figure. out here in their lives our tree and must say the scientists simulate the formation of a comet and its journey to earth and all just one so how do we do this comets are made of ice and dust we make some ice so we're going to glass of course was it always shows 3 molecules likely to be and such eyes water and methanol and ammonia the water 1st yeah tell me when i have the methanol. we're ok. these icy material is similar to that of which the newly formed comets were composed next the artificial comets long journey is simulated in fast forward.
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also we know that a week in the lab represents a 1000000 unit was already. operated i thought to tell me when you switch it on then i'll do the compressed air in the experiment begins in the chemical reactor there's a vacuum very close to that of interstellar space and the temperature is minus 200 degrees celsius. or not for me we made the ice we can see a bit here the sort of growth on the edge of the window. the r i c s bathed in all true violet light simulating solar radiation which breaks up the molecules. for all these 1st stage produces simple molecules which can then recombined to make more complex molecules this astonishing experiment is successful . in the class warfare and what we're going to do now is it warm the system a little dizzy with the ice. then begins the 2nd part of the
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experiment the comet leaves the outer region of the solar system and approaches the woman's zones with earth its. know what if the 2 like that can see the ice disappearing after a moment you can see bubbles forming itself so we're approaching a phase where the water is close to leaving the ice once we lose the water because we see a wide use film on the surface of the fuel that's new molecules that are form of fossil is such as at the end we have tiny droplets on the surface of the window which are quite visible to the eye and they constitute the organic matter that's been formed from the initial ice it was a radiator and then lot more md. 80 how deep your shellfish. the temperature in the reactor is now around 20 degrees celsius the artificial comet has finished its transformative journey. there are 5.
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at the end we get thousands of different kinds of molecules if we start with just remark your through the water methanol and ammonia or if we apply energy to earth and we form thousands of other molecules on. the experiment was a success. in this small chemical reactor there are now simple organic molecules similar to the building blocks from which life sprang forth. among these molecules homages of mind there are amino acids the base of all proteins found in every living creature. also in these droplets there are sugars essential for the construction of d.n.a. . the sewerage lot of old molecules like theirs ended up on earth have been in fact what we call meteorites are pieces broken away from comets and asteroids that came in our atmosphere and left their extra terrestrial organic material on the surface of primitive earth as us or for us that difference.
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having traveled from the outer reaches of our solar system the soul gannett matter ended its journey in the oceans of primitive earth. now we need to know what the environmental parameters were which allowed this matter to keep reassembling until it formed a living organisms. this is the next step of these groundbreaking experiment. be organic matter produced by the artificial comet is placed in an environment close to that of primitive earth. this could have been us all are pushing through and with this experimental approach we can change the environmental conditions like we can change for example the water. temperature of what we can change the wavelength of the imaginary sun that we're using you're going to music is a 6 time of a toilet what's very important for determining the various parameters of this or are they limited or not to suit are they unique to earth or could there be other
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environments elsewhere in our solar system or exoplanets for example or things like that dies off. panic molecules are present throughout the universe but the presence of the basic ingredients of life may not in itself be enough for life to exist. to go from the inert to the living may require a very specific combination of environmental conditions that we're only just starting to piece together.
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was last. our planet clearly provided the conditions necessary for life to arise very early on liquid water has been present on earth for 4400000000 years and the most ancient traces of life date from frequent 8000000000 years ago. on a geological time scale life appeared very quickly. what then was this particular medium which allowed the 1st living organisms to appear so quickly biologist put if you can see on lopez garcia here in mexico is studying the amazing adaptability of life in environments very similar to those of primitive earth. while she wound. it's crazy to nip if i think i'm i could be smaller but it's a pretty big if and deep it's going to be hard to get malice cannot kill any lovely . person it smells of sulfur so i love it shall we go event oh yes.
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horrific house you own and moreira are exploring the crater of the volcano as children in mexico. fumaroles boiling cauldron it's hot mud and springs the geothermal activity is evident everywhere here. gas rising from the bowels of the earth bubbles up through the acid lake. the 2 violet just 1st time is to measure the parameters of this extreme environment before looking for signs of life. what is it hot really hot yes. that's why there were up to 9092 sets still going up my 405000 or
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6.7 degrees or it comes out again it must be seriously hot inside that i must so i'll tell you. sit on the on if you ignore the plants at the edge of the craters this is like some environments of primitive earth with lots of volcanic activity and hydrothermal like to protect what is most hydrothermal activity was a constant ancram an ever. sit by. same yes 96.6 so we take a sample they're going to show duties that we have their cell phone on. these hydrothermal environment is very similar to that in which life 1st appeared and it
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doesn't take the 2 biologists long to find organisms which appear to thrive here. or i was a beautiful crazy well take a sample here chose to leave that by the way. it. was. despite these conditions which to us seem extreme there's abundant microbial life here the 2 scientists find and observe many varieties of bacteria organized into communities. they live so i get each month to add these organisms aren't primitive organisms yet from the microbial diversity we find here and in other ecosystems we can deduce the characteristics of the 1st living organisms.
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studying environments like these folks panic crater scientists can easily imagine the types of environments which were favorable to the formation of life on earth. yet there's a lot of hot water vapor or not i don't we can hear the water but we can't see it. on the other show we go to the like look at down over there. 4000000000 years ago the chemistry of life may well have begun in small puddles swept by a backwash book with deep with as many hypotheses about the origins of life suggests that one of the that there were tides leaving little legs small ponds which let the organic moloch.


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