slashdot.org/article.pl?sid=02/09/25/2329240&mode=thread&tid=160
Public Terminal Log in 56 Create a new account Related Links 57 New Scientist article 58 More on Space 59 Also by chrisd This discussion has been archived. Change The Fine Print: The following comments are owned by whoever posted them. This report is interesting, but I'd like to see the scientific article. There are alternative explanations, I'm sure, and I'm interested in seeing whether they've been adequately ruled out. Re:Life in the Atmosphere of Venus (Score:4, Informative) by 109 Hittite Creosote (535397) on Thursday September 26, @07:00AM ( 110 #4334815) The article should appear in an ESA special publication (ESA SP-518). Although New Scientist mentions ESA's Venus Express mission, it doesn't say whether the mission would have the necessary equipment to check for life. If they are absorbing UV, that would explain the presence of mysterious dark patches on ultraviolet images of the planet. Whenever there has been a possibility of life before, it has always been microscopic bacteria frozen in rock or ice. Nearly undetectable, and certainly nothing that would visually incite people. Huge swarms that discolor the atmosphere under ultraviolet light? If true, I'd bet that these images become more popular than Cindy Margolis. Wonder how many movies about vixens from Venus we 'll get if this turns out to be true. Insert a probe into the atmosphere (either from the orbiter or as a separate vehicle). This probe could use one or more of several techniques (parachute, winged design (no retro-thrusters at this stage as this may contaminate the samples)) to perform a fairly slow and controlled descent. The probe fills a small canister with gas (possibly several compartments from different altitudes) and propels it back up into orbit before the pressure and gravity gets too high 4. Dock the canister with the orbiter and send it back to earth. Just keep those pesky imperial units away from the project and you should be set. The probe could continue to send back data to the orbiter as it goes down, but it's probably too much to ask for a soft landing. And in one case, the plastic (probably not a thermoplastic, but still) lens cap got in the way of the soil sampler so the data sent back was an analysis of something the Soviets had put there in the first place. It's much easier to propel the canister from a decent altitude than if you wait until you're in deep. Gravity, pressure and heat all combine to make it unnecessary difficult (and expensive, since all propellants and other resources has to be brought along for the ride) to do launches from the surface. Or, just get the orbiter there and launch disposable probes into the atmosphere that can analyze the gases as they tumble down through the soup and relay back the results via the orbiter. This could be done as a cheaper and faster precursor to the "bring 'em back alive" mission, to help develop the technology, methodology and focus of the mission. It's much easier to propel the canister from a decent altitude than if you wait until you're in deep. Gravity, pressure and heat all combine to make it unnecessary difficult (and expensive, since all propellants and other resources has to be brought along for the ride) to do launches from the surface. Which means that getting stuff out of its gravity well is an incredible hassle. If you need an Ariane or a Proton to get an object off Earth, you're going to need another Ariane or Proton to get it off Venus again once you've landed it there. And the super-dense atmosphere is going to cause even more problems. No, launching from Venus is a problem that can happily wait until nuclear rockets or antigravity are feasible. Besides, if there is life on Venus, I'd much rather study it in situ than bring some back here. In the solar system alone, we've got Earth, Mars, Europa, Titan and now Venus. Of course, there's only evidence so far of life on one, but the very fact that scientists are even considering it is a testament to life's tenacity. Can someone who knows more than I tell us all how easy it'd be for UV light to penetrate to the required depth? Take this with a grain of salt - we know so little about our own solar system that we must treat all discoveries as hypotheses - nothing more, nothing less. They've known for some decades that bacterial spores are found throughout the Earth's atmosphere, including at very high altitudes. The Earth has a "dust tail" produced by the solar wind that very slowly strips off the outer atmosphere and blows it outward. This tail is something that interferes with some kinds of astronomy, so they must take it into account. The dust tail includes gases and fine dust particles, including things the size of bacterial spores. We've also known for decades that many such spores can survive indefinitely in space. Bacterial spores from Earth have been contaminating the outer solar system, probably for several billion years. Some of them will get picked up by meteoroids and comets and carried back to the inner solar system, so Mercury and Venus have also been colonized by these bacteria. And, of course, their descendants will have re-colonized the Earth. The solar system is a pretty messy place, when you look at it on a microscopic scale. One article I read back in the 70's did a rough calculation on a larger scale. We've made more than a dozen orbits since bacterial life arose here, spraying spores most of that time. The author calculated that by now the entire galaxy has been contaminated several times over by Earthly spores. Of course, we don't know how many could survive interstellar space for the required millions of years. I suspect Slashdot exaggerated the content of the posted article just to get page hits. Also, New Scientist is not one of the more reputable science news sites on the net (even though /. Oddly enough however it is believe that the smell produced would actually be a pleasant one to humans. Life Again (Score:2, Insightful) by 243 HeLLaCooL75 (608002) on Thursday September 26, @04:13AM ( 244 #4334198) This is getting so old. Assume that the number of bacteria double once every month; Wait 8 years and the mass has multiplied by 2^(12*8) = 8e28 times. I don't know how much a bacterium weights, but if we guess that it's one microgram, we'll have a mass of 8e19 kilograms. Obviously, the bacterial growth would run out of energy from sunlight before this, somewhere between the 7th and 8th year. Since all of that mass would be from atmospheric gasses, you would have chemically transformed 16 tonnes of atmosphere per square meter. Therefore, you would have transformed the entire atmosphere into bacteria. In any case, this illustrates that exponential growth can be remarkable. Remember that the observations were only about a certain area in the Venus atmosphere (70C etc), which might have the optimal conditions. At the altitude where life is suspected the temperature is about 70C and about 1 atmosphere. There are gases there which are not naturally found together. The article suggests something is actively producing them, quite possibly, life. The speculation is on the basis of finding two chemicals which don't typically persist for long in each others presence, Hydrogen Sulphide and Sulphur Dioxide. The evidence that life has fostered on the Earth's Sister Planet is a dire and grim proposition for the future of the human race. If we don't strike now, these phosphate-producing bacteria may, in billions of years evolve to a spacefaring race with religious viewpoints opposing The One True Way. We must strike now, to wipe out these bacteria before it is too late! It's the only chance that we have to eradicate these monsters before they can oppose Earth and America and Christianity! Illudium 239 Explosive Space Modulator (Score:1) by 294 Surak_Prime (160061) on Thursday September 26, @06:41AM ( 295 #4334751) Marvin probably could have told us about this a while back if WE weren't obscuring his view! President Bush Gave Speech this Morning (Score:1) by 300 espionage_7 (605753) on Thursday September 26, @08:58AM ( 301 #4335432) President Bush Gave Speech this Morning about the possibility of life on venus. In his speech...
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