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| ▲ | spott 7 days ago | parent | next [-] |
| Extraterrestrial in this sense is “didn’t come from earth”, not “aliens!”. |
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| ▲ | jibal 7 days ago | parent | prev | next [-] |
| Mars is extraterrestrial. The sun is extraterrestrial. Even the moon is extraterrestrial. And this article isn't about "coming here". As for your claims about the motives of people seeking extraterrestrial life or even wanting there to be such life, they are beyond absurd. Likening it to religious faith: it is belief without evidence. |
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| ▲ | bluGill 7 days ago | parent | prev | next [-] |
| Forget about why would they - they can't get here. The speed of light is too slow. They can't even detect earth exists much less there is life (dinosaurs). detectable signals won't reach then for a long time if they even can reach them. |
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| ▲ | rolph 7 days ago | parent | next [-] | | The existence of radio waves was first proven by German physicist Heinrich Hertz on 11 November 1886. The first commercial radio broadcast was transmitted on 2 November 1920 that means intentional radio signal was underway about 100 years ago. so suppose that signal despite the "low" power is heard by someone that listens very closely. they tease it out of the noise, and right away know what it is, and try to send back. at most, they are about 50 radio-years away, if thier signal reaches us now. beyond that, no signal from earth has propagated that far. https://en.wikipedia.org/wiki/List_of_nearest_stars https://en.wikipedia.org/wiki/List_of_star_systems_within_45... https://en.wikipedia.org/wiki/GJ_3929 https://en.wikipedia.org/wiki/WISE_1534%E2%88%921043 | |
| ▲ | tzs 7 days ago | parent | prev | next [-] | | > Forget about why would they - they can't get here. The speed of light is too slow. They could get here in a generation ship. Heck, we could almost build a generation ship that could reach another solar system. First, there is the traditional generation ship where you set up a closed self sustaining ecosystem. I don't think we are anywhere near able to make such a closed system that would last for a trip to another star, but give it another few decades and there is probably a good chance we'll know how. Second, there is another kind of generation ship that is called a seed ship or embryo ship. Your ship just carries a small crew, plus frozen eggs and sperm. During the trip as the crew ages you use artificial wombs to make babies from the frozen eggs and sperm and raise them to be the new crew. Any people you will need other than the crew at the destination (e.g., colonists if this is a colonizing mission) also come from the frozen eggs and sperm. With enough automation the crew could be quite small. I once calculated the mass of high calorie density food that would be needed to sustain a small crew for thousands of years and it was actually small enough that I'd expect a civilization maybe a century more advanced in space than ours to maybe be able to manage. With that you don't need to solve the problem of making a closed self-sustaining ecosystem. | | |
| ▲ | inejge 7 days ago | parent [-] | | > With enough automation the crew [of a generation ship] could be quite small. Other than the engineering challenges, we don't have the faintest idea how a really long-term crew is going to work socially and psychologically in a constrained, isolated, artificial environment. The closest analog are the naval/polar expeditions, which were unisex and under military or hierarchical command, none of them longer than a couple of years. Some perished (Franklin), some pivoted (Shackleton w/Endurance), some failed with loss of life (Scott), some worked (Amundsen). But all had options unavailable to a ship in vacuum, and were on an incomparably shorter timescale. |
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| ▲ | HappySweeney 7 days ago | parent | prev [-] | | I would caution applying our current understanding and limitations onto alien civilizations. I don't believe they will break the light barrier, but they may develop telescopes that can detect life from light-years away, and the stupendous travel times are possible with suspended animation or by stopping the aging process. | | |
| ▲ | bluGill 7 days ago | parent [-] | | While we don't know everything, we do know what we don't know needs to be consistent with what we know. Relativity is well supported by experiments, so whatever this thing is we don't know will have all the things you don't like about relativity. telestope limits exist in theory not just our manufacturing abilities. |
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| ▲ | cookiengineer 7 days ago | parent | prev | next [-] |
| These nutjobs still don't want to grasp the reality that the UFO sighting at Area 51 was the radar test of the A-12 prototype, which was made out of shiny unpainted titanium and done in the salt desert due to its properties of absorbing electromagnetic waves. And then some people that saw this around Roswell were spreading the rumor of UFOs because at the time that was the trend on television. Always bet on stupidity, they'll say anything to get their 5 minutes of attention on TV / social media. I mean, there were even senate and court hearings over this. Over a rumor that was disproven decades ago. The US (and probably by extend our species) has a serious education and information validation problem. [1] https://en.wikipedia.org/wiki/Lockheed_A-12 edit: Downvotes without comments create the downvote paradox, and kind of prove my point |
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| ▲ | reactordev 7 days ago | parent [-] | | It wasn’t the A-12 but a precursor. The A-12 didn’t come about until the late 50s. The Roswell incident happened in the late 40s. There were a few experiments with supersonic jet propulsion around that time. There were also Generals who would gladly stoke the UFO flames to protect the secrecy of their anti-radar research. I know this because my family was involved. | | |
| ▲ | cookiengineer 7 days ago | parent [-] | | > It wasn’t the A-12 but a precursor. The A-12 didn’t come about until the late 50s. The Roswell incident happened in the late 40s. > There were a few experiments with supersonic jet propulsion around that time. There were also Generals who would gladly stoke the UFO flames to protect the secrecy of their anti-radar research. You're right with the timeline that the initial rumors didn't start with the A-12 radar tests, but they were reinforced by it. Initially, Project Mogul's crash of the balloon array triggered the rumors, but it's not as fancy and couldn't be interpreted as an "alien spaceship", even at the time. https://en.wikipedia.org/wiki/Project_Mogul | | |
| ▲ | reactordev 6 days ago | parent [-] | | Occam's razor... It's big business now to continue to believe, humans have a natural tendency to fall into cult traps. |
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| ▲ | p_ing 7 days ago | parent | prev | next [-] |
| Maybe they have a relativistic kinetic kill system and we’re on borrowed time. |
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| ▲ | reactordev 6 days ago | parent [-] | | Maybe they're make-believe because there's no evidence or fossil record other than giant feathered reptiles and things that came from the sea? Dig up a T-Rex skull and see if your 2,000 B.C. brain doesn't think "Dragons!" |
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| ▲ | decremental 7 days ago | parent | prev [-] |
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