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Everything posted by todofwar

  1. Congress is what I meant by the jobs in districts thing. Also, there is the other concern around the culture at NASA today. Plenty of Mars Sample Return people are probably getting nervous and trying to find ways to make sure they don't lose money to manned missions to the moon (I happen to think sample return is also pointless from a science perspective but that is going way off topic). And there is no way we put a human on the moon in the 2020s and get back a sample from Mars in 2030 unless we double NASA's budget, probably more. Still, I think NASA, with all its many faults, remains the best space agency out there and can get an astronaut to the moon. I have pretty low faith in Starship, but I also had low faith in the Falcon 9 and was convinced a VTHL was the way to go so I could be wrong. I do worry about landing Starship on the moon because the moon is all regolith, might not be able to handle something that heavy without a dedicated platform first.
  2. I suppose it becomes a philosophical question, but did NASA land on the moon before or did Boeing? And is the SLS train wreck on Boeing or NASA? I think the latter is more on how the contract bid process and need to provide jobs in districts overrode other concerns, which is what always happens with federal projects. And of course NASA is capped at what it is allowed to pay civil servants. But the CLPS program I think shows NASA might actually be learning from the lessons of SpaceX, namely that the best use of tax payer dollars is to create a competition among commercial providers with NASA as the main but not necessarily only customer. The big question becomes, in regards to this thread, if we have a SpaceX launch for a Moon Express manned lander and China buys the first trip, who got credit?
  3. I think NASA has a bit of "trying to do everything" syndrome, but it's worth remembering right now NASA is focused on developing technology to enable Science. And we have compelling science cases to go just about everywhere, and one astronaut on the Moon probably equals ten or more Curiosity class rovers on the Moon. This gets into the whole manned vs unmanned argument but I think NASA is doing better than people think.
  4. I believe SpaceX timelines about as far as I can throw an F9. Besides that, end of the day, what does Musk want with the Moon? He wants to colonize Mars and his pie in the sky architecture for that does not involve the Moon. SpaceX has not even tried to enter into the commercial lander provider race which now has several serious players and a commitment from NASA to buy. They will probably be involved as a launch provider, but they have made 0 moves towards becoming a lander provider even though the new program is set to mimic a contest SpaceX already won once. My money is still on NASA. People are going nuts over China landing a couple small landers and a rover, talk to me when they land a rover the size of a mini cooper on Mars. Only threat to NASA being first is if the next president decides to once again shift focus to humans on Mars which is entirely possible, but to be honest when it comes to outer space there is NASA and then everyone else. It's like they are an NFL team and everyone else is still playing at the college level.
  5. It's not just about size and weight though, wind is a nice steady source of free energy. And if you use a kite, you can access much faster speeds not too high off the ground.
  6. Don't forget wind power. It's slow, but steady and reliable and with higher mass than our own atmosphere.
  7. All sounds like one of those things that may feedback into earth applicable systems. I'm sure there are places we'd like higher temp circuits, if the tech was available.
  8. The hydrogen won't get stored at the surface, it's for rocket fuel. You can use copper for your electronics as well, but I'm imagining you won't have allot of circuitry. Just some hydrolic pumps to work the arms of the scooper. The smart section would be very small, and the first thing cooled by the flowing water. The water reserve would be kept isolated as much as possible, some low pressure helium insulation should work pretty well. Once the reservoir of water starts getting too hot it can be vented at a higher rate to finish filling the piston and allow liftoff. But the system is designed to have the water reach boiling point, just in a controlled fashion. Also, pretty sure pure graphene is colorless but I might be wrong about that.
  9. Not sure what the necessary threshold is, but I know that band gaps only refer to gaps in energy states. Distributions within those two states is governed by boltzman equations, which are temperature dependent. As you ramp up temperature, you begin to populate the higher energy state more. In order to make use of that gap, you need a difference in population that can be exploited. If you populate the higher state too much, you end up with a negligible difference in populations, that means you have one state, and no band gap in the most extreme case. I believe it also plays into tunneling, which can be an issue for sophisticated circuits.
  10. I wonder if there will come a time when we don't do EVAs anymore. Seems there should be a way for a drone operated from the relative safety of the inside of the iss to accomplish all those tasks.
  11. People freak out too much about the Venusian surface. Pressure: absolutely a non issue. We handle many times that pressure every day. Ever heard of submarines? Acid: again, non issue either on the surface or even if you were hanging out in the clouds. Sulfuric acid is the most produced chemical on earth. Yeah, iron doesn't like it, but we have plenty of ways to deal with acid. High temperature acid resistant coatings are a budget away from reality. We can already rust proof things with graphene coatings, it's just expensive. Temperature: this is the real problem, but not as bad as people think. Lead is really low melting, so the whole "melting lead" thing sounds cool but it means nothing for most alloys. Steel will handle it just fine, though it may warp a bit over time so you'll need occasional replacements. What this does mean is you'll need some kind of way to keep your smart sections cool, but you can have those in a well insolated and actively cooled section. Wind speed: also non issue, though storms may be a problem at certain latitudes. You will be floating along with the wind at high altitude, from your frame of reference you won't be moving at all. It will be possible to air launch to orbit, that's not much of a problem. Real issue there is fuel, Venus has very little hydrogen which is a key ingredient in all our chemical fuels (kerosene is, in terms of molar ratios, mostly hydrogen). So you'll have to bring in the hydrogen from elsewhere, already started a thread on that one and the conclusion was near Venus asteroids as the best source. And at the surface the wind is a slow breeze. The mass of the atmosphere may require some anchoring to avoid drift, but the wind is actually slow enough to cause issues with wind power (hence the need for a kite system, already being developed by Google for earth applications). My suggested system: airship with good sensors aimed at the surface looks for concentrations of unobtanium. Lander deployed that is little more than a back hoe that scrapes the surface. May come with its own drill, or you could drop some earthquake bombs like we used in WWII to loosen up material. It dumps material into a bucket that floats up to the atmosphere where it is refined, and launched to orbit. Other idea for the lander: it has a tank of liquid water. The liquid is used as a coolant, in a system designed so that once the liquid boils it exhausts into a piston. The piston generates energy for the lander, which is anchored to the ground. Once the piston is full, it has enough buoyancy it lift itself to the upper atmosphere. Water will condense, so the lander will need to be caught by another airship that never lands. It takes the ore to the refinery, the piston has reset itself and goes back down to the surface e for more material. Only the bucket of ore need float up, so the piston will reattach itself to the lander base and continue mining.
  12. I think we're basically going to be depending on space peta and space green peace to protect our biosphere from total annihilation. Unrelated but they'll merge anyway, but one of my biggest pet peeves was definitely in one of the iron man or avengers movies where Tony stark is giving a presentation at MIT and at the end he says all the students projects have been fully funded. Afterwards, someone walks up and asks if maybe some of that money could go to faculty, and it's played off like that faculty is unimaginative and greedy unlike the students with genuine good ideas. Who do people think do all the research at universities? Undergrads do what grad students tell them to do and grad students follow the lead of their faculty adviser. If those students projects are funded than that money will go to faculty one way or another.
  13. Related to the final final final form trope in rpg games. Normally, armies get more desperate and throw more and more rash things out as you get close to defeating them. They throw everything into round one and hope there is no round two. See: Germany in wwii. Now, individual battles can have this sort of escalation if it was say a sneak attack that didn't immediately succeed so you start sinking more and more resources into it to try and force the other side. See: also Germany wwii. You may enjoy planetary annihilation. The only game I've played where smashing your own planets moon into the enemy planet is an available and encouraged way to end a conflict.
  14. Does it matter where the reactions take place? Thinking about what you would make in hydrolox aside from water, none of them will be stable and your number two product will probably be peroxide, which will then act as a monopropellant but it would probably persist long enough to not go off in the main reaction chamber.
  15. Only thing I will point out is the visible light spectrum is optimal for vision because many electronic transitions happen in that region, sometimes down to the UV or up to IR, but most spectrometers in chemistry labs operate between 200 and 800 nm because that's where you get the bulk of useful information. IR sensing eyes could also be useful, and some organisms can detect them, but usually in addition to visible light organs. Anything above UV is likely to be too damaging, and you don't gain much in the ultra ultra violet region anyway.
  16. Of course, the question becomes which tech would have advanced faster. Let's say I build a graphene hard drive in a lab. It stores 10x more than the current market leader, and has a superior read out rate (I really don't know computer hard drive terms so bear with me). By the time I get it into a product, conventional hard drives have outpaced mine or made it so the benefit is no longer worth the added cost of scaling production to be able to match what can be made on existing machinery. But my graphene drive will improve in certain metrics at 1.05x the rate of conventional, and match improvement rates for the rest. Long term, it will be the better solution. So, is the market driving us to a local minimum in the end? It is (edit: potentially) a big issue with many technologies out there.
  17. I will agree a marker just doesn't have the feel of chalk, but it's not enough to outweigh the other benefits for me. Of course, chalk is much more eco friendly too. No, you're describing computational chemistry which is different from theoretical. Computational chemists apply the theory others come up with, not to say theoretical chemists don't apply their own theories.
  18. I always wonder about this. What do mathematicians do all day? I asked some theoretical chemists, apparently they do just write on chalk boards allot (I must be the only scientist I know who prefers dry erase boards) and then put the equations into mathematica. Still can't wrap my head around that, the thought process that goes into just staring at an equation until some new way forward pops up.
  19. Interesting. I would think running in the hamster wheel would get sweat to actually flow down off of you like it would naturally, since you are in effect running in 0.3g. Maybe getting in one of these: Instead might work better. You can get going up to a faster speed, getting closer to 1g, and with the added benefit of having less tidal force. And, you can bolt it onto a track, so you can start from stationary allot easier. Downside is, your legs won't get the same level of force as they would from walking around in a 1g environment so who knows what that will do for bone loss. Whole point of this is to accomplish something close to 1g for health reasons, without the need for a complex rotating hab which needs to be much wider due to the RPMs necessary at smaller radii. But if it's only an hour or so at a time, I think a small 5m diameter wheel might work nicely.
  20. They apparently did it in space lab, not sure how big that was. I'm thinking a harness would be needed to train on it at first, but over time humans are capable of pretty impressive things.
  21. Log scales have a habit of diminishing differences. It's not insurmountable, but it is a big problem that needs to be adressed. And the type of radiation is different too, it's very high energy radiation that penetrates allot of conventional shielding.
  22. So, what I guess the take away is we should just be ok with half the astronauts we send somewhere dying from radiation related illnesses until we figure out better treatments and shielding? Being serious now, back then it seems the value of human life was lower in general, we don't accept anyone dying on the way to Mars.
  23. No, the wheel is stationary the whole time, the astronaut runs around generating their own g force. Think of it like a car going along the side of a track, the faster it goes the harder its pressed against the track wall. From an observer outside, what is happening is the astronaut is propelling themselves forward to collide into a wall, but instead of colliding they redirect themselves along the wheel. Faster they propel themselves forward, harder they "hit" the wall. Much the same way a runner is doing little more than falling forward and catching themselves over and over again. Now that I think of it, some kind of rigid bar for the astronaut to push against as they get themselves going will probably be better overall than a tether. That way, while running slower, they can push themselves into the wall for some added traction. As they really get going they won't need to push themselves down anymore. So some kind of trapeze type bar hanging down on a rigid rod from the center of the wheel. Yeah, that's one of the issues. The section of the ship would need to weigh enough to make the astronaut's mass almost negligible. Don't know just how massive off the top of my head though.
  24. Was thinking about the whole artificial gravity thing, and about the usefulness of inflatable modules thing, and realized the two might work well together. The general problem with inflatables is you need to fill them with stuff, so really what good does the inflatable part do for you except require multiple launches? So I thought maybe just having some big empty space for astronauts to feel a little less claustrophobic would be nice. And maybe put some excercise equipment in there too. And that's when I thought, hamster wheel. If you make a wheel 5 meters across, and tether someone to the middle of it, and they start running, then if they hit 8 miles an hour (that's not bad at all really), their feet will experience 0.5g of centripedal force. Now, they will feel some tidal forces. Their head will experience about .1g in this scenario. Running at 12 miles an hour (5 minute mile pace) gets their head up to .23 and their feet to 1.2. Basic idea is, launch an inflatable with a five meter diameter internal environment. Have a pole run through the center, and a tether attached. It might need to be able to swing the person a bit to get them started, but once they're moving they should be able to propel themselves forward. Nice, lightweight 0 energy solution for artificial gravity for long term habitation. So, for anyone with more knowledge about medicine, the question is, would simulating gravity by running in a circle have any benefit? I'm thinking thirty minutes to an hour a day (probably not all at once) should help somewhat. They already have those bungee chord treadmill things after all. Optional design: Make it a bike attached to a rail, easier to get to speed and keep the body more prone to avoid tidal issues. Possible issue: The mass of a grown human running around will throw off the center of mass, and will introduce some angular momentum to the station. Might need to be compensated with something. Maybe the bike solves this a little bit, just add a counter weight to at least preserve a center of mass. If gravity is an issue on the Moon or Mars though, at least those won't be problems.
  25. Yeah but again, those didn't stray into the belts or deep space, so not much better than the prolonged exposure of humans on the ISS. We can get radiation levels easy enough, but actually seeing their effects on biological systems is more challenging. Ants aren't the best analogue organism, but even sending up some nematodes will give lots of useful information on the effects of space radiation on multicellular organisms.
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