tag:blogger.com,1999:blog-8587336.post4508590094367422164..comments2024-03-29T06:22:47.638-07:00Comments on CONTRARY BRIN: Space News!David Brinhttp://www.blogger.com/profile/14465315130418506525noreply@blogger.comBlogger80125tag:blogger.com,1999:blog-8587336.post-29814781427109852832022-06-10T19:45:24.607-07:002022-06-10T19:45:24.607-07:00Alfred etc the answer is that Space ... is.... har...Alfred etc the answer is that Space ... is.... hard! It was easier to change ancient crimes of prejudice than it was to make wheel stations spinning to Strauss waltzes.<br /><br />onward<br /><br />onward<br />David Brinhttps://www.blogger.com/profile/14465315130418506525noreply@blogger.comtag:blogger.com,1999:blog-8587336.post-12287701465405378022022-06-10T17:43:56.183-07:002022-06-10T17:43:56.183-07:00onward
onward
onward<br /><br />onward<br /><br />David Brinhttps://www.blogger.com/profile/14465315130418506525noreply@blogger.comtag:blogger.com,1999:blog-8587336.post-72172099639736040272022-06-10T17:21:01.916-07:002022-06-10T17:21:01.916-07:00duncan,
Your back-of-the-envelope calculations do...duncan,<br /><br />Your back-of-the-envelope calculations don't convince me. I can do them too… and have for solar sail ideas. <br /><br />1. It's not empty out there. (We really ARE inside the Sun.)<br /><br />2. The sun emits a fair amount of UV and soft x-rays impacting the fragility of your structures.<br /><br />3. The sun emits a very gusty particle flux further impacting your structures and their control systems.<br /><br /><br />On Earth, much of the surface is hostile to human life. We manage because the air is breathable and we have enough tech to buy time in those places learning how to make things that reduce 'hostile' to 'manageable.' Over the last few millennia, we've been converting 'hostile' to 'manageable' as well.<br /><br />In space, only a few places are hostile. The rest are incredibly toxic. <br /><br />It's mostly in the toxic places where your engineering assumptions will be tested. <br /><br />———<br /><br />I don't want to sound like a nay-sayer with all this. We CAN build large structures out there and will learn how to do it. All I'm arguing against is that they'll be the cheap option. If I had to gamble my own money, I'd bet on nuclear being the cheapest once you get out past NEO's. Near Earth, I'd argue for PV's running equipment and small mirrors to bake things but not smelt. Sintering* of lunar regolith should be possible on Luna, but metal reduction is something I'd bet against for the foreseeable future.<br /><br /><br />* Sintering is important if you want to beat the dust problem. Tourists will quickly lose interest in Luna when they realize how nasty the dust is. Sharp, tiny fragments. Worse than hostile.Alfred Differhttps://www.blogger.com/profile/01170159981105973192noreply@blogger.comtag:blogger.com,1999:blog-8587336.post-5318800201646878912022-06-10T17:02:47.040-07:002022-06-10T17:02:47.040-07:00Projects funded like that through NIAC are part of...Projects funded like that through NIAC are part of why I'm not more negative about NASA in the modern age. I've never been inclined to fault everyone in the agency for the fact I cannot buy a tourist ticket to Luna just yet, but I admit I've come pretty close at times.<br /><br />One of my attitude drivers stems from an event in the mid-90's. I was chasing after solar sail documentation and asked the JPL archives for copies of Halley Rendezvous reports. Apparently I was the first civilian to do so after the Cold War was over, because I triggered a declassification process. I wasn't in a rush and received a box of stuff several months later. I was a happy pig in the mud until I noticed some of the reports never got written. I asked about them and the archive people said they never received them. The report references documents from various contractors… who didn't finish before the money ran out.<br /><br />I learned from friends that this wasn't unusual. The political purpose having been met (keep staff employed) no one cared much about the final project artifacts. That struck me as fraud and still does, but it technically isn't if the government funding source doesn't care either. A wink and a nod makes it clear what is actually being purchased… and it wasn't results.<br /><br />———<br /><br />I wound up working on some software to simulate sails out there that tried to represent perturbations correctly. There were a number of code blocks owned by research teams that approximated possible missions, but nothing I could get my hands on treated the problem properly. One included sunlight forces, but ignored spherical harmonics. Another looked at several perturbations, but only over long time integrations. It was frustrating because I wanted to search for commercially feasible flight profiles to and from promising targets. I got part way into it and discovered the usual hindrance. No one had computers fast enough to do what I imagined except the big guys. Solar sail research was not done by the big guys. No one funded it much back then.<br /><br />I suspect we CAN do these things today. Every so often I get tempted to revive that work on my own dime.<br /><br />———<br /><br />I sincerely hope NIAC demands all final reports be completed. You never know when Joe Citizen Engineer will develop an itch and want to see what his money is doing… then leverage the work to avoid re-inventing what's already been done.<br /><br /><br />Alfred Differhttps://www.blogger.com/profile/01170159981105973192noreply@blogger.comtag:blogger.com,1999:blog-8587336.post-91323563208829289172022-06-10T15:58:52.669-07:002022-06-10T15:58:52.669-07:00Alfred
The stresses on a mirror would only become...Alfred<br /><br />The stresses on a mirror would only become significant at the kilometer size range <br /><br />And a square km of mirror would be focusing a Gigawatt of power - even out at Jupiter that would be 40 Megawatts <br /><br />A soap bubble would do for the mirror - a 1 km square mirror could need a frame of 1 cm angle aluminium ??<br /><br />Tradeoffs - the lighter the frame the greater the number of position control modules <br /><br />But the cost of the mirror, frame and position control modules would be a rounding error compared to the cost of the energy receiver at the focus duncan cairncrosshttps://www.blogger.com/profile/14153725128216947145noreply@blogger.comtag:blogger.com,1999:blog-8587336.post-22623019508279096382022-06-10T15:50:29.582-07:002022-06-10T15:50:29.582-07:00A.F.Rey - which way would a democrat vote?
If the...A.F.Rey - which way would a democrat vote?<br /><br />If they have Boebert as the GOP candidate then there is a greater chance of the GOP losing<br /><br />On the other hand if Boebert wins its worse than a sensible Republican<br /><br />There is no "correct choice" - only guestimates <br /><br />duncan cairncrosshttps://www.blogger.com/profile/14153725128216947145noreply@blogger.comtag:blogger.com,1999:blog-8587336.post-91940201666160096112022-06-10T13:14:52.459-07:002022-06-10T13:14:52.459-07:00Sticking a little politics into the conversation, ...Sticking a little politics into the conversation, the Democrats in Laura Boebert's district seem to be taking your advice and voting in the Republican primary.<br /><br />https://www.electoral-vote.com/evp2022/Senate/Maps/Jun09.html#item-8<br /><br />They aren't registering as Republicans, though, but as Independents, which allows them to vote in whichever primary they prefer. But you can't imagine them changing party affiliation just to continue voting Democrat. ;)<br /><br />The only problem is there are not enough of them. Only about 3700 have changed affiliation, and Boebert won by about 10,000 votes. But it may be enough to tip the balance come June 28. :)A.F. Reyhttps://www.blogger.com/profile/08102355714883828348noreply@blogger.comtag:blogger.com,1999:blog-8587336.post-2298007567480815862022-06-10T11:28:01.480-07:002022-06-10T11:28:01.480-07:00scidata,
That's were the nukes come in. Not s...scidata,<br /><br />That's were the nukes come in. Not stored solar energy, but high energy density anyway. We'll need that tech to bootstrap toward the vision Duncan describes.Alfred Differhttps://www.blogger.com/profile/01170159981105973192noreply@blogger.comtag:blogger.com,1999:blog-8587336.post-48799217635448860122022-06-10T11:26:44.754-07:002022-06-10T11:26:44.754-07:00Developing very large mirrors and sails and solar ...Developing very large mirrors and sails and solar concentrators for asteroid refining are all projects we have funded (some continuing) at NASA's Innovative & Advanced Concepts program - (NIAC) .<br /><br /><br />David Brinhttps://www.blogger.com/profile/14465315130418506525noreply@blogger.comtag:blogger.com,1999:blog-8587336.post-83763920460977777612022-06-10T11:23:40.800-07:002022-06-10T11:23:40.800-07:00Gerold, alas, you know some things... not others. ...Gerold, alas, you know some things... not others. Asteroids - even 'near-Earth" NEOS - take more TIME to get to than lunar surface. Hence Luna is better for living people. That plus shelter and gravity for bones and swimming pools.<br /><br />So Luna WILL likely see settlemens, even cities. And no way that is a reasonable near or medium goal.<br /><br />Asteroids have vastly more useful stuff. Except for water ice, Luna has none. Near term oxides refining is as mythical as 'Helium Three."<br /><br />NEOs are MUCH less energy costly to get to and back. For robots it is a no brainer.<br /><br />For now, Luna is for tourists. Period. And we should let the eager tourists rush for their photo shoots, like we did 55 years ago.<br />David Brinhttps://www.blogger.com/profile/14465315130418506525noreply@blogger.comtag:blogger.com,1999:blog-8587336.post-7163139729818988572022-06-10T11:00:17.161-07:002022-06-10T11:00:17.161-07:00If only there was some way to gather solar energy ...If only there was some way to gather solar energy where it's abundant then transport it out to where it's needed. Some sort of electricity storage device.scidatahttps://www.blogger.com/profile/07152319593457629592noreply@blogger.comtag:blogger.com,1999:blog-8587336.post-71421371982461042172022-06-10T10:47:51.573-07:002022-06-10T10:47:51.573-07:00Duncan,
The load isn't just sunlight. There a...Duncan,<br /><br />The load isn't just sunlight. There are a number of perturbing forces. <br /><br />I used to play with solar sail designs years ago (how I met our host) which also have the complicating need to unfold if launched from Earth. You can avoid unfolding, but you can't avoid gravitational perturbations and solar wind.<br /><br />It only looks like empty space out there. The fact is the Earth orbits the sun through the top of the Sun's gusty atmosphere. Build your mirrors and you'll notice. [The wind gusts and the objects being orbited aren't spheres.]<br /><br />You need structure and attitude control for the mirrors. Put your engineering hat on and break out the CAD and FEM tools. It's not as simple as you think.Alfred Differhttps://www.blogger.com/profile/01170159981105973192noreply@blogger.comtag:blogger.com,1999:blog-8587336.post-4553490180093632172022-06-10T10:21:03.984-07:002022-06-10T10:21:03.984-07:00That's the same reasons Cheyenne Mountain outs...That's the same reasons Cheyenne Mountain outside of Colorado Springs was chosen. The old Ent Air Force Base was at the locus of telephone and telegraph lines as the Springs was another major stop for cattle drives on the way to Denver. Also the location of Ent was also good for radio repeaters. Relocate the base into a nearby block of granite to protect it from nuclear attack. Now of course most of the old Air Force bases in Colorado have been reassigned to Space Force john fremonthttps://www.blogger.com/profile/06505620790054721035noreply@blogger.comtag:blogger.com,1999:blog-8587336.post-29515183767692884282022-06-10T02:56:38.208-07:002022-06-10T02:56:38.208-07:00Alfred
Re cost of solar in the outer system
All y...Alfred<br />Re cost of solar in the outer system<br /><br />All you need is mirrors - if the sun is 10 times as far away then a mirror ten times as large (100 times area) -<br /><br />Mirrors should be dirt cheap - the only "load" is sunlight <br />spinning disc maybe?<br />Half a huge soap bubble balloon? <br />The technologies that are being developed for solar sails would work - only no need for super duper light - just light would do<br /><br />the expensive bit is at the focus - turning sunlight into whatever - and that stays the same cost no matter how far out you go <br /><br />Going further out increases the cost of the supercheap bit duncan cairncrosshttps://www.blogger.com/profile/14153725128216947145noreply@blogger.comtag:blogger.com,1999:blog-8587336.post-58155057637283494862022-06-10T01:16:11.454-07:002022-06-10T01:16:11.454-07:00Duncan,
Energy costs in free space should be incr...Duncan,<br /><br /><i>Energy costs in free space should be incredibly low.</i><br /><br />Heh.<br /><br />Because sunlight is plentiful, right? <br />Try moving further out in the solar system where most of the easier resources are found. <br /><br />Papa Sol kinda arranged this and he's had a few billion years to set up the game for us. Where sunlight is most plentiful, everything has been thoroughly baked. The easy stuff to get has already been chased out of the solar system baked away and dispersed as ions.<br /><br />In case it isn't clear, I'm saying energy will be cheapest where it is least useful. Working out further from the sun will require structures that have to be maintained. They won't be cheap because it takes energy to make them in the first place.<br /><br />"Costs should be incredibly low" always provokes skepticism in me. I hope you are right, but my gambling instinct says to bet against you.<br /><br />As for volatiles in a hole… I agree up until someone uses some of them for heat transfer. If the hole is baked hard enough, it is a pipe once you drill it out.<br /><br />For Belt operations, I'll go on record as saying y'all are going to need nuclear energy. Slow fission to provide heat for industrial purposes. It's a damn long way out there.<br /><br /><br /><br />Gerold,<br /><br /><i>being an HG nomad on the moon isn't very practical</i><br /><br />I'd argue it is one step short of dying. If it doesn't happen to the fool trying, it will get their kids. I'd say this about most of space too, but especially Luna's surface.<br /><br /><i>…because of the cost of…</i><br /><br />Yes, but…<br /><br />This is exactly the problem markets solve for us. We often dislike the solutions, but it works. If someone is willing to pay $X for commodity Y at location L on calendar day T, they offer their end of a futures contract. If $X is high enough, someone buys into their end of the contract and the game is underway.<br /><br />Those contracts can't be written at the moment because $X must account for the fact that engineers don't know how to do a lot of what's needed up there. <br /><br />Yet… there are launch companies building rockets and promising to fly object Y from pad P on roughly calendar day T. THAT engineering knowledge is advancing fast. Some of them are getting pretty good* at delivery Y to a relatively exact location L (defined by orbit parameters)… so what do WE want to put up there? What can WE do that advances the engineers so we get a little closer every day to those commodities futures contracts?<br /><br />* WE can put things in sun-sync orbit on a regular basis now with a ride on scheduled, dedicated buses operated by SpaceX. What do WE want to do?Alfred Differhttps://www.blogger.com/profile/01170159981105973192noreply@blogger.comtag:blogger.com,1999:blog-8587336.post-52194226755324458422022-06-10T00:06:08.036-07:002022-06-10T00:06:08.036-07:00Alfred: being an HG nomad on the moon isn't ve...Alfred: being an HG nomad on the moon isn't very practical. But because of the cost of escaping the earth's gravity well we need to source locally as much as possible. Lift the manufacturing tools but obtain raw materials outside earth. <br /><br />The moon has lots of local material and it's close to earth. Asteroids are great but they're a long ways off. Travel time and reaction mass required to get there, synch velocity, gather the materials and then get to where it can be processed are all costs. <br /><br />The moon also has a gravity well and that makes it costly to get off. But depending on how much surface ice is available in the perpetual shadow craters, oxygen and hydrogen - rocket fuel - may not be a limiting factor. If ice is not abundant, then maybe rail gun propulsion - that's how Heinlein got heavy stuff off the moon in Harsh Mistress - is the way to go. Solar energy converted to electrical power could make that work if we can cover the South Polar peaks with solar cells. Need to be able to make them on site of course. <br /><br />I've always pictured a solar smelter floating at a Lagrange point. That way you can get 24 hour continuous insolation and go as hot as needed. But maybe the earth-moon L1 point could be the site of focusing mirrors with a "crucible" on the lunar surface (?)<br /><br />I love the solar smelter idea but the engineering would be tricky. geroldhttps://www.blogger.com/profile/05140093281920523064noreply@blogger.comtag:blogger.com,1999:blog-8587336.post-45751639509561245252022-06-09T23:51:09.532-07:002022-06-09T23:51:09.532-07:00Hi Alfred its the ones that "make" and s...Hi Alfred its the ones that "make" and sell the volatiles that will use locations with low delta V requirements<br /><br />Energy costs in free space should be incredibly low<br />Energy costs when you are down a hole will be high as your mirrors will need to strong to resist gravity and atmosphere and your power source will move across the sky and hide half the time<br /><br />So volatiles that are down a hole will need to compete with volatiles made from the nasty oxides with cheap energyduncan cairncrosshttps://www.blogger.com/profile/14153725128216947145noreply@blogger.comtag:blogger.com,1999:blog-8587336.post-32928562707743354442022-06-09T09:30:55.210-07:002022-06-09T09:30:55.210-07:00Gerold points out correctly that tightly bound oxi...Gerold points out correctly that tightly bound oxides are a bitch to break up. That's almost every 'resource' on Luna.David Brinhttps://www.blogger.com/profile/14465315130418506525noreply@blogger.comtag:blogger.com,1999:blog-8587336.post-23238676548470312022022-06-09T01:42:06.381-07:002022-06-09T01:42:06.381-07:00Duncan,
Volatiles are critical.
Put your enginee...Duncan,<br /><br />Volatiles are critical.<br /><br />Put your engineer hat on a bit and consider answers to the following questions.<br /><br />1. What fraction of car users make their own cars for personal use?<br />2. What fraction make some part of their car that is critical to its function as part of their maintenance of the vehicle?<br />3. What fraction refine their own fuel for use in their car? (May include biodiesel.)<br /><br />I suspect those fractions aren't zero, but pretty damn close. The last one is probably largest, but not huge.<br /><br />Now shift your attention to what your life might be like on the Moon… or anywhere else out there. Are you really going to make your own oxygen? Manufacture your own water? Craft every other detail you need to keep alive and functional? Nah. You will want to buy it. <br /><br />If you make it all yourself, you are a one person market. We call such people HG nomads. If people in your colony make it all themselves, you live in a commune or tiny ordered community. Neither of these options are going to leave you with enough time to teach your kids the technology skills they'll need to keep doing it. Go down this path and your fellows will retreat into the kind of poverty humanity faced for most of our existence as HG nomads.<br /><br />Nah. You'll buy your oxygen if you can. You'll have water shipped to you if you can. You'll buy your tech from elsewhere if you can. Pulling that off means you have to have something to sell. Fortunately, there is something up there that is worth a frickin' fortune to people who want to make money doing ANYTHING else. Fuels, oxidizers, and all the other things 'life' needs. Whether people are up there in large numbers depends on all three, but it starts with fuels and oxidizers. Those start with volatiles.<br /><br />Trade requires moving stuff from here to there. Movement requires delta-vee which requires fuels and oxidizers. (aka volatiles)<br /><br />Ignore the gold and platinum. Stick to the lower atomic numbers and the molecules they make.<br /><br />Think like a mining engineer.Alfred Differhttps://www.blogger.com/profile/01170159981105973192noreply@blogger.comtag:blogger.com,1999:blog-8587336.post-50562477489157754572022-06-09T01:25:08.627-07:002022-06-09T01:25:08.627-07:00Duncan: breaking down mineral oxides takes a lot o...Duncan: breaking down mineral oxides takes a lot of energy but a solar smelter in zero-g might be a good way to get high enough temperatures to volatilize minerals. Moon dust has a lot of oxygen, silicon, aluminum, iron, magnesium and titanium; blast it with enough concentrated solar radiation and it'll fractionate into constituent elements. I'm not sure how to process it afterwards however; zero-g is nice because you don't need a crucible for containment, but what do you do with a blob of super-hot molten or gaseous matter? Gravity is nice for fractional distillation and cracking, but if some smart space manufacturing engineers can figure out a way to process hot elemental matter out in the vacuum things could get interesting. geroldhttps://www.blogger.com/profile/05140093281920523064noreply@blogger.comtag:blogger.com,1999:blog-8587336.post-48486649873480767932022-06-09T00:45:20.576-07:002022-06-09T00:45:20.576-07:00I'm certainly not convinced that a moon base i...I'm certainly not convinced that a moon base is necessary or advisable. The arguments in favor of orbital platforms are strong. Whether a human presence makes sense is also debatable. Life support is heavy/expensive. A big part of that tradeoff is the pace of robotic and AI tech. Right now people still have a big advantage when it comes to intelligence and flexibility. How long will that last? 20 years? 40? Do we want to wait for them to catch up? <br /><br />One advantage of a moon base is ready access to matter and energy. The South Lunar Pole has areas with near constant sunlight and (potentially) large deposits of surface ice in perpetual shadow craters. This could eliminate a major drawback: the lunar gravity well. Water makes good rocket fuel if you have enough energy. If we can make solar panels/film on site, huge amounts of energy could be made available. With energy all things are possible. <br /><br />If we want/need to have people in space, the moon has a couple more advantages: shielding from radiation and gravity. I don't know if 1/6 g is enough to prevent the kind of physiological degradation we get in zero g, but that would be very helpful. <br /><br />One other "resource" we get off-planet is never discussed: near zero ambient temperature. Seems like this could be very useful for electronics. Quantum computing might be more practical, and free superconductivity might have all kinds of advantages. <br /><br />I know if I was a transcendent AI I'd want to live in the cold. Hard to think straight at 300 K ambient.geroldhttps://www.blogger.com/profile/05140093281920523064noreply@blogger.comtag:blogger.com,1999:blog-8587336.post-19574418143425766752022-06-09T00:42:41.353-07:002022-06-09T00:42:41.353-07:00Alfred
"Volatiles"
How nessesary are the...Alfred<br />"Volatiles"<br />How nessesary are they?<br />With abundant energy from the sun we may not need "volatiles" - instead we should be able to break down the solid "rock" - rock has lots of oxygen - and some rocks have hydrogen<br /><br />Something common and on the surface may be a better source of the elements we need than drilling for "volatiles"<br /><br />We have a tendency to think in terms of compounds rather than elements - which is a reflection of the way to do things on a planets surface with lots of compounds and a dire shortage of energyduncan cairncrosshttps://www.blogger.com/profile/14153725128216947145noreply@blogger.comtag:blogger.com,1999:blog-8587336.post-81910838015507517482022-06-08T22:43:09.293-07:002022-06-08T22:43:09.293-07:00scidata,
Anything you put in the Easy-Bake oven f...scidata,<br /><br />Anything you put in the Easy-Bake oven for 3 billion years is going to have a brick-hard exterior. The Sun isn't as bright out there, but UV still breaks up molecules.<br /><br />I think the only plausible debate regarding Phobos volatiles is whether it's worth drilling to get them or lifting them from Mars. My suspicion is the drill is cheaper, but if crazy tourists are going to-and-fro... who knows?<br /><br />And yah... comet nuclei that haven't been in the oven as long are more interesting. If... they have reasonable orbits.<br /><br />------<br /><br />There is an old debate among space advocates about how things will unfold. At times it's more like a war of religion. If I have to pick a side (I'd rather not), I usually argue that we will make some use of the Moon mostly from orbit and then move on to NEO's. I'm only interested in economic development when I pick a side, though. <br /><br />Scientists will go where their interests lead. They don't have budgets large enough to make a dent in what the engineers need to know and economic development is mostly about engineering and finance.Alfred Differhttps://www.blogger.com/profile/01170159981105973192noreply@blogger.comtag:blogger.com,1999:blog-8587336.post-89558686918089125692022-06-08T19:08:46.597-07:002022-06-08T19:08:46.597-07:00Re: ansible waldoes
That's what the Turing Tes...Re: ansible waldoes<br />That's what the Turing Test is all about. A sufficiently advanced ghost in a machine is equivalent to human intelligence. However, it's not romanticism to point out that that's only hypothesis, not proven fact. Piers Anthony delved into this in "Macroscope", as have many others ("The Fly", "Transcendence", even "2001"). I call it 'secret sauce', others go full wingnut (eg Francis Collins). A poetic way of putting it:<br />"A totally unmystical world would be a world totally blind and insane." - Aldous Huxleyscidatahttps://www.blogger.com/profile/07152319593457629592noreply@blogger.comtag:blogger.com,1999:blog-8587336.post-62818550404942825292022-06-08T19:02:47.809-07:002022-06-08T19:02:47.809-07:00Paradoctor - that time gap is the best reason for ...Paradoctor - that time gap is the best reason for an AI<br /><br />It would not have to be a very powerful AI as it would be being led by the human - duncan cairncrosshttps://www.blogger.com/profile/14153725128216947145noreply@blogger.com