• Content Count

  • Joined

  • Last visited

Posts posted by MBobrik

  1. One with a six-seven digit budget could probably build a more or less autonomous robot that generates a random pattern and then imprints into the crop. But that would ultimately count as "caused by people" anyway.

    Extraterrestrials, as the question tries to lead us ? No, unless they have the same motivation as human pranksters, and no interest in actual communication. But then, occam's razor.

    Extraterrestrials with psychology that causes them to consider "paint geometric shapes over the first suitable big surface" as their first choice of communication ? Maybe, but by finding suitable crop fields and waiting with painting until no witness is around they would demonstrate they got a lot of knowledge about humans. Enough knowledge to realize that human psychology is different and this is not the best way to communicate with us. And someone building interstellar spaceships is bound to be smart enough to figure out.

  2. Dude, they tried it in a B-36. The 48 tons of shielding deemed necessary for an operational aircraft was *with* shadow shielding the crew cabin and using the aircraft structure and fuel tanks as additional protection. With the experimental aircraft, they used the water coolant tanks for the reactor as well (as the X-6 was to have been air-cooled).

    Actually, It was only 12 ton and its design was far from optimal ...

  3. Aviation accident investigation delves into what caused the accident, why the accident occured, are there any underlying design or operational flaws, and how we can prevent further accidents. The ultimate goal is to save lives, but the number of people dead in any given accident does not by itself govern its severity. Investigations need to performed objectively and scientifically, otherwise there's no point.

    Are you implying I that said they should be not ? Surely, when investigating causes of an accident, the number of people killed is not relevant. However, when evaluating the overall safety of that given means of transportation, the number of people who got killed using it is the most important number.

  4. I assume the focus on accidents rather than the deaths those accidents cause is because each incident is a separate fatal breach of safety, while deaths are

    totally dependent on how many souls happen to be on board.

    Accidents vary in severity. Counting accident like accident seems absurd to me. I don't think that 'accidents' of four small business jets, like bumping into the terminal at say 1 mph, emergency landing because of drunk passenger brawl or such can be lumped together as '4' accidents, and meaningfully compared to '3' accidents involving obliterated airplanes and three digit body counts.

  5. Deaths are not considered the defining variable when if comes to aviation safety by experts.

    I am not buying that. to be a little over the top, this would be like saying that four crashed paragliders with the worst injury being a broken leg are worse than MH370, MH17, QZ8510 put together.

  6. Except that they were never able to lift enough shielding mass to produce an aircraft capable of carrying a useful payload. They only ever managed to shield the flight crew from the reactor, and only ever pulled the control rods when it was already in flight. Who wants to service an aircraft that is spraying neutrons at you? Who wants to live under a flightline with a lightly shielded reactor flying overhead every half hour? What would reactors at full takeoff power do to an airport?

    A hydrogen tank and all other machinery between the reactor and the crew/ payload would provide more than adequate shielding for the crew. Ground facilities could be protected by an *external* shield. And the runway would have to be from materials that are resistant to secondary neutron activation, there should be no human nor animal outside within several miles distance from the airport while this thing is taking off. But once in air, and over ocean, the inverse square law will offer enough safety. Surely it would leave a trail of ozone, nitrogen oxides, and traces of carbon 14 in its wake but if the traffic is sufficiently low this would not be a serious environmental problem. If it were to crash, reactors running on high enriched uranium are small and opposed to all other reactors uses, run briefly. They therefore won't accumulate large amounts fission products. the worst thing that would happen is a local spot of radiated water that dissipates quickly into irrelevance.

    Concerning construction and operation, it would presumably operate like SR 71 except it could fly higher because its engines don't need oxygen. Then, at some point, external air would be replaced with hydrogen, and it would continue nerva-style.

  7. Combine this idea with the autorotation idea before, maybe we can have a capsule with the cake inside with those wings, and launch it self out of the tungsten rod shield using explosive on impact and let the capsule rotate down slowly.

    Small objects with high surface/weight ratio aren't subject to very high temperatures.

    So, as a special challenge, one can make the cake exactly thin enough to get baked during reentry but not burned.

  8. That could be a good measure of "hidden" progress in rocketry. Hidden because no one is actually doing this stuff so we can't directly compare. But we could use (realistic) contemporary apollo style mission cost estimates compared do the inflation adjusted cost of the actual apollo program as a measure of how or whether our technology has advanced from 1960's. The only problem I see in this, is, that today's project costs tend to be extremely underestimated, so we would have to adjust for that.

  9. Who here is saying we shouldn't or aren't "building Rome"? Advocating for a practical approach to increasing our capabilities in and knowledge about space is not the same thing as advocating that we do nothing. There are missions that robots can do better than people, there are missions that people can do better than robots and there are missions where using robots is currently our only alternative to doing nothing.

    This si maybe you are advocating. Nibb is more like "there are no missions that people can do better, so send in only robots"

  10. The foreseeable future is something like the next 20 or 30 years. Not 20000. There is no point in discussing stuff that might or might not happen beyond 20 or 30 years, because we have no idea what sort of world we will be living in by then. You're just being obtuse here.

    No you are being obtuse. If we restrict ourselves only to things that are surely pay back in the next two-three decades, like you are suggesting, there won't be any long term future worth speaking of.

  11. No, it's like saying you won't go to the gym until you learn to walk. We can barely crawl.

    Even walking can one learn only by putting effort into trying.

    And who is talking about postponing anything? I'm talking about using the best learning tools we can afford within the budgets that we have available.

    Look who's talking:

    The problem is that what any of us "wants" is irrelevant. The point is that there is no rational justification for manned exploration in the foreseeable future

    So no rational point to try walking in the foreseeable future. Stick to crawling. Perhaps in another 20000 years when obstructive attitudes like mine wane.

  12. The problem is you keep wording your statements in such a way that for you it's apparently a foregone conclusion that AIs and robots will eventually turn against us or otherwise not be our friends and allies, up to and including more extensive unmanned space exploration as such a conclusion.

    No, I am saying, if we set them free to evolve roaming the galaxy, but we stay put here stagnating, at some point we will stop being equal partners to them. All that I am saying is, that the "we stay put here stagnating" part is bad. And is bad on its own irrespective of sentient AIs.

  13. What difference does it make if we go interstellar in 200, 2000, or 20000 years? You and I won't be around to see it, and civilization will be very different by then? The point is, we are not ready yet. We'll get there if we need to and when the time comes.

    This is like saying you won't go tho the gym until you grow muscles. Guess how long will that take. By postponing indefinitely 'till we are ready' we won't get ready. Ever. It's the same as gym. The only way of getting ready is by putting effort into trying.

  14. Most kids learn pretty early in life that they cannot get everything they want. ...blah...blah...


    That was exactly the level of smugness I was expecting from you. The rest of your post can be summed up with three words. Negativism, greed and shortsightedness.


    And one more thing. There is an obvious rational, even economic justification of not giving up on the rest of the universe. Its most pedestrian version goes like "what is the expected accounting value of the rest of the universe ?" It's just beyond the capability of shortsighted thinking.

  15. You're the one constructing strawman silliness about artificial sentient beings. I'm merely talking about reducing the communication loop by using space probes that are slightly smarter than the ones we have. For example, instead of beaming back terabytes of data, analyse the data on-site to detect and extract specific patterns and transmit that particular data at a higher resolution or with a higher priority. Or instead of micromanaging each wheel motor from mission control, just input a set of coordinates and let the rover figure out how to get there. That's hardly creating a master race of robot overlords.

    I am sorry, I failed to notice that even though I started about what would be necessary to explore beyond the distance where the time delay makes things like just better compression, data filtering, autonomous driving, and such insufficient, you can not even imagine that far and thus you couldn't be talking about that situation. Hard to make it obvious to you... so lets crank it up a little... imagine a probe to alpha centauri. how it could gather data efficiently when the response won't come back until long after the mission ends ? The only solution, methinks, is that the probe itself understands what it found and adapts its further exploration accordingly. anything less would lead to gross inefficiencies - first the probe catches a glimpse of something, it will take eight years to redirect it to examine it more, when it turns out to be something unexpected, further eight years to tell the probe to change its approach, and so on...

  16. Robots and probes are not "them". They are "us". They are the tools we use to explore places where we can't go and to see stuff that we can't see, because we have biological limits. We have always used tools to improve our limited capabilities. A space probe is no different.

    We use robots regularly to repair deep-sea pipelines or to inspect nuclear reactors or to fly over enemy territory. Do you suggest that we should send people in those places too, just because it's more adventurous?

    You are comparing the uncomparable. Pipelines with the universe. Simple tools with artificial sentient beings. I am perfectly willing to leave routine maintenance at the bottom of the sea to the robots (we can go there any time we want anyway), but I am not willing to pass on the rest of the entire universe. And while today's simple tools are mere extensions of ourselves, future sentient AIs would be independent beings on their own, not us. We may consider them our progeny, but they won't be us. You may be content with creating a species more resistant to the rigors of space travel, and leaving the future to them, but I am not.

  17. It's just a silly strawman argument. If we are clever enough to design interplanetary robotic exploration missions, then surely we are clever enough to design them so that they don't want to destroy us.

    No we won't. You can't predict, control and forever predestine thinking of something as clever as you are. They would most likely not destroy us because they would have no motivation to do so, but that would be beyond our control.

    You only need to make AI that can detect interesting patterns and pre-analyze data so that you can shorten the feedback loop

    Except the level of pre-analyzing that would allow the robot roam free and search, eventually dealing with contingencies, while the earliest possible human reaction can be next day to decades, would amount to human level od understanding of what's going on.

    The truth is, we don't know what technology we might or might not have in 50 years when we decide to focus on exploring Jupiter or the Kuiper belt. I'd rather look at goals that are actually reachable.

    The truth is, that short term thinking is one of the mankind's greatest scourges. If it weren't we would be already firmly established on Mars and planning to move to Jupiter next.

  18. Something I've never personally understood is this irrational fear of robots and AIs that some people seem to have, why do you guys think like that? Why are advanced robots and AIs immediately "EVIL BAD TERROR NO NO NO"?

    Are we out to exterminate squirrels ? No. I was not talking about AIs being deliberately speciecidal or even malevolent. Just about evolving past their initial programming and going their separate ways to the point where we are just another species of local fauna for them.