walterpthefirst Posted July 26 Share Posted July 26 https://www.jpl.nasa.gov/news/nasas-perseverance-rover-scientists-find-intriguing-mars-rock Scientists caution that this is NOT a confirmation of past life on Mars (a 7) but is a 1, a possible signal that has been detected and must be thoroughly checked. Thank you, Walter. 1 Link to comment Share on other sites More sharing options...
older Posted July 28 Share Posted July 28 I think it is only a matter of time before we confirm that life exists outside our planet. We keep finding bits and pieces and at some time those bits and pieces will come together. One of the questions I get asked when I take my telescope to the astronomy club's public outreach events is if I think life exists out there. My answer is that there are somewhere between 100 and 400 billion stars in the Milky Way, and there are at least 100 billion galaxies, and we are finding more every day. And we have found more than 5000 exoplanets and some of those are in the so-called sweet spot that would be good for life. So in my mind the probability is high that there is some sort of life elsewhere. 1 Link to comment Share on other sites More sharing options...
walterpthefirst Posted July 28 Author Share Posted July 28 6 hours ago, older said: I think it is only a matter of time before we confirm that life exists outside our planet. We keep finding bits and pieces and at some time those bits and pieces will come together. One of the questions I get asked when I take my telescope to the astronomy club's public outreach events is if I think life exists out there. My answer is that there are somewhere between 100 and 400 billion stars in the Milky Way, and there are at least 100 billion galaxies, and we are finding more every day. And we have found more than 5000 exoplanets and some of those are in the so-called sweet spot that would be good for life. So in my mind the probability is high that there is some sort of life elsewhere. I'm in complete agreement, older. The crazy thing is that we'll probably confirm life in other star systems before we confirm it in our own solar system. I say that even though there are tentative hints of microbial life high in the atmosphere of Venus, the possibility of ancient microbial life on Mars and the possibility of life (microbial or complex) in the sub-surface oceans of Europa, Enceladus and other moons of the outer planets. Fact is, with the JWST we're better geared up to look for life on the planets of other stars than we are to look for it on the planets orbiting our sun. Venus To directly detect the presence of acid-tolerant microbes in the Venusian atmosphere you'd have to launch a probe that can stay aloft for weeks or months. That means some kind of balloon with its scientific payload suspended underneath in a gondola. Getting all that technology to work is a big, big ask. Mars We're already running into the buffers here. The rovers can only do so much and what they can't do in situ needs to be done on Earth. But NASA has to work within budgetary constraints and the kind of sample return mission they'd like to do is uber-expensive. A next generation copter to succeed Ingenuity, would allow us to roam far and wide and hover over terrain where no rover can go. But if anything suggestive of life is seen, we're back to square one again. How do you get a sample back to Earth for testing? Jupiter The JUICE and Jupiter Clipper missions might find evidence of life-bearing molecules on the likes of Europa, Ganymede or Callisto. But they can only do that via remote sensing. The same would be true for any future mission to the moons of the other outer planets. (None planned that I know of.) So, best case scenario, scientists would have to infer that some kind of life was responsible for the signals they were seeing. No kind of sample return is possible with current technology. All of the above have the additional problem that these are all environments that are either not very Earth-like or are very unlike Earth. Besides Mars, none of these candidates are in our Sun's habitable zone. But that situation doesn't apply when it comes to the JWST. Other Star Systems Here's where the JWST scores highly. It's designed to find the signatures of various molecules and chemicals in the atmospheres of exoplanets. Like this. Webb Discovers Methane, Carbon Dioxide in Atmosphere of K2-18 b - NASA Other positive factors are the sheer number of targets it can observe and the wealth of information we already have about these exoplanets' masses, orbits and parent stars. We will know where a given star's habitable zone is, how similar a given exoplanet orbiting in that zone is to Earth and we can therefore infer what its surface temperature and atmospheric conditions are likely to be. Should the JWST detect what look like biosignatures in the atmosphere of an Earth-sized planet orbiting in the habitable zone of its star this news will leapfrog any findings in our solar system. Ok, once again we will be forced to infer what we cannot directly test. But the case will be so much stronger because we will be looking at an Earth-like environment that appears to display just what you would expect to find there. Molecules of oxygen, methane, chlorophyll, ozone and similar. The signatures of biological activity. This is why I suspect we will find indications of life on far distant worlds before we find any on our neighbouring one. Thank you, Walter. 1 Link to comment Share on other sites More sharing options...
older Posted July 28 Share Posted July 28 4 hours ago, walterpthefirst said: How do you get a sample back to Earth for testing? What if we figure out how to do the testing there? 4 hours ago, walterpthefirst said: Molecules of oxygen, methane, chlorophyll, ozone and similar. The signatures of biological activity. My "what if" is that we presume certain elements are required for life or are signatures thereof. But what if our presumption is wrong? What if there are "things" that can reproduce themselves in some alternative environment? Link to comment Share on other sites More sharing options...
walterpthefirst Posted July 28 Author Share Posted July 28 1 hour ago, older said: What if we figure out how to do the testing there? Indeed. What if? I assume that you're referring to a robotic mission with such capability, older? 1 hour ago, older said: My "what if" is that we presume certain elements are required for life or are signatures thereof. But what if our presumption is wrong? What if there are "things" that can reproduce themselves in some alternative environment? Oh I agree. But the scientists responsible for future missions already have their "follow the water" policy in place. Which means that if there are "things" out there, based upon different chemistries we might never detect them. A case in point being the critters that might be floating in Venus' upper atmosphere. That planet was written off as a candidate for life due to its high temperatures and extreme acidity. Then what happens? Phosphine, a gas associated with living organisms here on Earth, is tentatively detected. Who knew? Thank you, Walter. Link to comment Share on other sites More sharing options...
older Posted July 28 Share Posted July 28 7 hours ago, walterpthefirst said: Indeed. What if? I assume that you're referring to a robotic mission with such capability, older? Yes. When we look at what can be done with today's remote systems, I would think it would be possible to construct a testing device that could be operated from Earth. To stray a bit from the topic, I sometimes think that we are in Plato's cave; our perception of the universe being limited by what we can observe. A blind person is not going to be able to fully comprehend a sunset. What is on the other side of a black hole? If we can make a Mobius band, could the universe be a Mobius sphere? 1 Link to comment Share on other sites More sharing options...
walterpthefirst Posted July 29 Author Share Posted July 29 9 hours ago, older said: Yes. When we look at what can be done with today's remote systems, I would think it would be possible to construct a testing device that could be operated from Earth. The expense, danger and logistics involved in putting human boots on the Martian ground will probably mean that we're going to go with remote systems for the foreseeable future. I remember the heady days when NASA was planning to be on Mars by 1978, using NERVA rockets. And here we are, almost half a century later, with a manned Mars landing still a remote possibility. NERVA - Wikipedia So, yes, remote systems it will have to be. 9 hours ago, older said: To stray a bit from the topic, I sometimes think that we are in Plato's cave; our perception of the universe being limited by what we can observe. A blind person is not going to be able to fully comprehend a sunset. What is on the other side of a black hole? If we can make a Mobius band, could the universe be a Mobius sphere? This thought had crossed my mind too. 1 Link to comment Share on other sites More sharing options...
pantheory Posted August 4 Share Posted August 4 According to my readings, they can't rule out non-biological causes as yet. But it's something we've been looking for ever since we first went to Mars. My own hypothesis is that when we find life on Mars, the moon, or the moons of Jupiter etc., it will be related to the first life on Earth. I believe life existed in the planetary cloud that created our solar system and such microbial life preceded the creation of the Earth and sun, therefore was not first created on Earth, or even necessarily in our solar system first as is presently believed. As to the first men on the surface of Mars, my bet is still on Musk first 60/40. Link to comment Share on other sites More sharing options...
pantheory Posted August 9 Share Posted August 9 On the topic of Mars and the future of life there, whether native, from Earth, or bio-engineering it for Mars, scientists are now developing more realistic and less costly methods of warming the planet which is a part of terraforming it (making it more Earth-like). https://www.sciencedaily.com/releases/2024/08/240807225455.htm Link to comment Share on other sites More sharing options...
pantheory Posted August 12 Share Posted August 12 The study, link below, found a number of liquid water reservoirs on Mars. So far they haven't found any liquid water reservoirs less than about 5 miles deep below the surface as yet. Depending on the geography and geology, however, I expect they will eventually find at least some liquid water reservoirs much shallower. Pumping down heated atmospheric gas can also turn sub-surface ice reservoirs into liquid water. And of course all know based upon studies and aerial observations, that there is plenty of water and some atmospheric gas CO2 frozen in the polar ice caps of Mars. The area of the south polar ice cap is a glacier area about twice the size of Texas. To use that water, you'd have to truck or train it away, or build a pipeline and pump it to your place of need. There could be no canals at present , because with such a thin and cold atmosphere, liquid water could not flow for long and would quickly evaporate or turn into ice. https://www.bbc.com/news/articles/czxl849j77ko Link to comment Share on other sites More sharing options...
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