Supersonic Man

June 21, 2018

hydrogen economy? how about methane instead?

Filed under: Hobbyism and Nerdry,science!,the future! — Supersonic Man @ 4:52 pm

Ever since the seventies, there’s been an idea floating around that someday, in order to replace fossil fuels, we’d start using hydrogen as our main chemical fuel.  We’d have hydrogen tanks instead of gasoline tanks, and hydrogen pipelines instead of natural gas pipes.  The hydrogen would be produced from water with either renewable or nuclear energy sources, and then whenever we needed a chemical fuel, we’d use hydrogen.  And wherever we needed a portable source of electric power, we’d use hydrogen fuel cells.  Our cars might be fuel cell powered, for instance.

Since then, fuel cell cars have advanced pretty well, and building a fleet of electric cars which get their power from hydrogen fuel cells looks fairly doable.  There are even some demo filling stations which allow you to fill up a fuel cell car with hydrogen, if you have one of the test vehicles.

So that part is doable, though nobody’s sure if there’ll be any need for it.  Cars might do just as well by simply using batteries, and plugging in to charge, as many people do today.  Making a new network for delivering hydrogen to cars might be an unnecessary expense.

But what about all the other things we use fossil fuel for, besides transportation?  What about heating our houses, and fueling our stoves and ovens?  Could we, for instance, substitute hydrogen for natural gas?

I think the answer is that we could, but maybe we shouldn’t, because there’s a better idea.  An approach which lets us keep using the natural gas infrastructure that we already have.  Switching to hydrogen would entail replacing most of it, because a pipe or a valve that safely contains natural gas can easily fail at containing hydrogen.  Since it is the lightest of all gases, one of its properties is that it can find its way through leaks which, to any ordinary gas, aren’t leaks at all.  Every piece of every pipe, and every valve in every appliance, would have to be either carefully tested, or replaced.

We can avoid all that with one simple step: taking the hydrogen we produce and converting it into methane.  Natural gas is 95% methane, and if we make it artificially, it could be used as a direct replacement for gas.  And the way we’d do that is with a process called the Sabatier reaction.  In this process, hydrogen is combined with carbon dioxide by means of a metallic catalyst.  The oxygen is stripped off of the carbon atoms and hydrogen takes its place.  The result is methane, plus leftover oxygen.

The best part is where we get the carbon dioxide: out of the atmosphere.  At first, we could take it directly from the smokestacks of industries which still burn fossil fuel.  (Steelmaking, for instance, might have a hard time using anything but coal.)  Later, as the scale increases, we could just separate it out of regular air.  This makes your home’s stove and furnace and water heater carbon neutral.

With some further chemical processes we could probably convert the methane into longer chain hydrocarbons, producing oils and so on — substitutes for things like butane or kerosene or diesel or gear oil… or even gasoline for classic car enthusiasts.

Between battery cars and methane conversion, maybe there wouldn’t be all that big a market for straight pure hydrogen.  It would definitely have some uses, but I don’t think all that big a part of our energy supply would be used in hydrogen form.  We might, however, use hydrogen to store solar energy from midday for use at night.  Such hydrogen might be produced directly by vats of algae, then fed to stationary fuel cells as the sun sets.

If a big methane convertor works, we should of course encourage its use.  We’ll have tax credits for making carbon-neutral methane, and penalties for fossil fuels.  The rival approach of getting gas by fracking might even be banned outright, because of its harmful side effects.  This assumes, of course, that at some point we overcome the reactionary political forces who want to prop up the oil and coal industries, and let all the profitable advances in renewables be done overseas.

One cool thing is that methane making machines are being developed right now, as part of the space program.  Not NASA’s space program, but SpaceX’s private program.  They’re building it for future Martian explorers and colonists, so they’ll be able to make their own rocket fuel for flights back to Earth.  Who knows, maybe at some point they’ll use the machine to fuel rockets here as well  so they can say they have carbon neutral satellite launchers.  Both of the major reusable rocket companies say methane is the fuel they want to use.

Of course, some other rockets will keep on using hydrogen.

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June 3, 2018

Trends in rocketry

Filed under: Hobbyism and Nerdry,science! — Supersonic Man @ 11:07 am

I’ve been taking an interest in the space industry and orbital rockets — a field which is evolving very rapidly nowadays.  So far this year we’ve seen the debut orbital flights of the Electron, the Falcon Heavy and Falcon 9 Block 5, and seen a new record set for the smallest rocket to put up a working satellite.  In the remaining months, we’re expecting the maiden flights of the LauncherOne, the Kuaizhou 11, the Vector R, and the Starliner and Dragon 2 crew capsules.  We just might see one of those capsules take live astronauts to the Space Station by the end of the year.  And the next couple of years will have plenty of action too, with several lunar landers being sent up by different countries, and more new vehicles making their debut: the SLS, the Vulcan, the New Glenn, the Dream Chaser, and more.

With so much short-term activity, it may be hard to spot the longer term trends, but I think I can lay out a few here:

1.  China is rapidly overtaking Russia as a superpower in space.

China now has three different families of major rockets, and are planning a fourth which, if they pull it off, will be bigger than Apollo.  They also have three different types of small solid rocket in service.  They’re starting on their own space station, and will attempt next year to bring moon rocks back to Earth.  Their rate of satellite launches is comparable to that of market leader SpaceX, while Russian rockets are losing business.  Trying to compare budgets can be misleading when different currencies are used, but on paper, the Chinese are spending more.  Their level of investment and ambition is impressive.

The Russians, on the other hand, are struggling to consolidate programs and cut costs.  Their Angara modular rocket program (which was supposed to modernize their fleet) is in difficulty, and rival aerospace organizations are fighting over shares of a shrinking pie.  They’re trying to phase out obsolete systems such as the Soyuz, and finding them difficult to replace.  And they’ve alienated Ukraine, where some of the best rocket builders from the old days are based.  For small solid-fuel launchers, all they’ve got is one type which is made from recycled ICBMs, which they quit using in 2006 but are now trying to bring back.  Unless China runs into difficulties in the next few years, Russia will soon be the #3 spacefaring nation, if they aren’t already.

I would say a weaker Russia in space is a good thing, as long as Putin or anyone like him remains in power.  But for a bunch of Russian rocket experts to be looking for jobs, eager to be hired by dubious regimes, is probably not a good thing.

2. SpaceX is slowly decimating traditional aerospace companies who build large rockets, and nobody looks likely to beat them.

At first, SpaceX launched expendable rockets, just as everyone else did.  It took them years to develop a booster that could land itself dependably, then a bunch more time to show that these landed boosters could be refurbished into flyable condition, then more time yet to study the lessons learned from refurbishing, and upgrade the rocket so it can hopefully be reflown without needing an overhaul.  They still have not yet reached the point where they can launch a rocket, land it, wash off the soot, refuel it, and launch it again the next day, which is their goal.  They believe it’s close now, that their “Block 5” is the rocket that can do it… but they haven’t proven it yet.

And yet in spite of how the great cost savings promised by rapid reuse are still just a hope for the future, they are already undercutting the prices of all the traditional launch providers who sell large rockets, forcing them to lower their margins and reduce costs.  In fact, they have been for years.

Since a lot of launches are still done by governments, there’s a lot of inertia which keeps big government contractor rocket builders such as United Launch Alliance in business… but to the extent they’re exposed to the free market, they’re hemorrhaging customers.  This hits the Russian rocket builders particularly hard.  They haven’t got a path forward to cut costs with reuse.  Both ULA and the EU’s Arianespace do have such plans, though they will take years to implement, but as yet the Russians have nothing.  The for-profit parts of their space businesses are already shifting their investment from making rockets to building satellites, which is where the money now is.  The Chinese also have nothing yet, but in their case there seems to be a lot of willingness for the government to keep propping up uncompetitive rockets, including models that already have superior replacements in use, while also developing new ones.  That can’t keep up forever, but it shouldn’t have to: they’re looking at the question of reuse and are bound to figure something out eventually.

Speaking of the plans of ULA and Arianespace, what they’ve got coming is probably sufficient to match the price cuts that SpaceX has brought to the industry so far, but if rapid reuse works it will start a second round of cost-cutting, and it seems likely that both will remain years behind if they attempt to catch up.  The plans they have in the works now are conservative, and won’t be able to make a really dramatic difference in cost — they’re both aiming to recover only the engines at the bottom, while still discarding the rest of the rocket.  Those engines are the most expensive part, but they only account for around half of the total cost of a launch.  (Arianespace is also now starting a small scale research program for vertical landing, just to see whether it’s a technique they might eventually want to use, but they have no firm plans yet to follow it up with anything commercial.)

So who is there who is in a position to compete?  Really, only one company is looking good right now.  It’s the one other company which has already implemented soft landings and reuse: Blue Origin.  They’re the only ones in a position to challenge SpaceX head-on.  But even they may struggle to compete, regardless of how much Amazon money they have behind them, because their forthcoming New Glenn rocket is too big.  It’s going to be even more large and powerful than SpaceX’s Falcon Heavy (which can orbit thirty tons and still land all three boosters).  And I note that when SpaceX first planned the Heavy, they thought it would end up doing half of their business, but over time, its role is getting smaller and smaller.  They are not finding many customers for such heavy lifting.  A lighter rocket with the same technology can probably offer a better price to the majority of customers.  The New Glenn also has a much larger, and presumably much costlier, second stage than the Falcon has, and they’ve got no plans for making that stage reusable, so that puts a floor under how low they can cut their prices.  And in general, Blue Origin has a more conservative engineering approach than SpaceX does, and this leads to much less aggressive cost reduction.

I think the only way that Blue Origin is likely to come out ahead is if either there’s an unforeseen boom in large heavy payloads, or if SpaceX develops a bad safety record while Blue Origin’s remains clean due to taking more time and care than SpaceX does.  That scenario is definitely plausible… but the safe bet is definitely on SpaceX.

Speaking of rockets that are too big, the shortage of heavy customers may leave SpaceX regretting the size of the fully reusable “BFR” system they plan to build in the next decade.  They might find that the most profitable rocket they could have built is just like a BFR but only a fifth as massive.  The dramatically low costs they say the BFR will bring might not materialize if the market for large payloads remains limited.

But even if the BFR proves to be too large, SpaceX still has the upper hand, because every other approach has a per-flight hardware cost floor that the technology can’t go below, while the BFR, if it works, could in theory fly for only the cost of the fuel.

There is one wildcard company which might challenge these two: Reaction Engines Ltd, makers of the SABRE engine.  They say they’ll be able to use it to make a single stage orbital spaceplane, but even if they don’t, a suborbital plane which acts as a substitute for a booster stage could end up being quite competitive.

Whether Blue Origin or Reaction Engines succeeds or not, I think the large rocket market is likely to see a shakeout.  The Russians are feeling it already, and ULA was wise to plan ahead for replacing their Atlas and Delta lines with the more competitive Vulcan.  ULA has had to shed employees, but I think they’re responding fairly well to the challenge, and the fact that their existing rockets have the best success record in the business may count for a lot.  They’ll never catch SpaceX on price but I suppose they should still have customers at the more premium end of the launch market, especially if human safety is involved.  In the end, though, even the survivors will probably have to downsize.  And a company like Orbital ATK, which has no idea how to do reuse and has no chance at winning on either cost or track record, might be completely out in the cold.

3. The shortage of small commercial launch services could easily become a glut… but the resulting balance could be vulnerable.

While SpaceX and its ilk get the attention with their big rockets, most of the satellites that people would like to launch don’t need a big rocket.  Rocket Labs’ Electron, with its capacity of around a quarter ton, is big enough to cover about two thirds of the commercial market, they estimate.

There are lots of older small rockets, many of them based on solid fuel missiles, but their costs per kilogram are usually uncompetitive with the otherwise less attractive option of waiting to hitch a ride as a secondary payload on a large rocket.  But now there are new companies such as Rocket Labs which aim to bring the cost of small launches downward.  The trouble is, there are too many new companies.  They’re cropping up in many different countries.  They can’t all get the dozens of launches a year that they will probably need in order to become profitable.  Also, the Chinese are rapidly commercializing their small solid launchers, at cheap prices.  Small-launch industry insiders are already starting to mutter the word shakeout, even though for the moment there is still a long backlog of unmet demand.

I will note that none of these small launch companies is yet offering anything truly revolutionary in terms of cost lowering.  They’re all just reducing costs incrementally.  None of them, for instance, has any solid plans to embrace reusability, except for one small outfit in Spain which is probably years away from putting up its first satellite.  If someone does, they could make this whole batch of companies uncompetitive.

Some of them are hoping that reduced prices will lead to increased volume, but the reductions being hyped just aren’t that dramatic.  It’s in the large launch market that such dramatic price cuts may have a major effect.  If SpaceX succeeds at rapid reuse, they could cut their prices far below anyone else’s without any sweat at all, giving them something fairly close to a monopoly on large non-governmental launches, or a duopoly if Blue Origin matches them.  (Or perhaps more likely, they could keep their prices higher so the market remains more open and competitive, but make a huge profit margin.)  But nothing equivalent is on the horizon in the small market.  They not only seem likely to spread their market too thin, but also to fall even further behind on cost compared to the option of piggybacking on large launches.

Conclusion: what the market is missing is a highly reusable small launcher.

If some company wants to disrupt SpaceX the way they disrupted the aerospace dinosaurs, the way to do it is to make a rocket which takes advantage of the latest advances in reusability, and applies it to payloads of under one ton.  It would not be all that expensive to develop; such a venture would be easily within the reach of some existing aerospace companies, or of the Russians.  But it may be out of reach of most of the small startups currently pursuing the light launch market.

Or it may not.  Rather than developing the complex systems that allow rockets to land themselves on concrete pads, a small booster might easily be recovered with a simple parachute, and if you can snatch it out of the air before it hits the ground or the drink, it might be very easily refurbished.  More than one small-launch company is adding parachutes to their boosters in the hopes that they might recover some intact, and at least one is waterproofing it, in the hope that it can splash down undamaged.  And if the empty rocket weights only a ton or less, instead of the thirty or so that a heavy booster might weigh, then snagging a parachute with a helicopter or airplane is actually quite doable.  The Air Force has done it for years, and United Launch Alliance is planning to use this approach to recover their jettisoned engines.  This cheap lightweight approach might not sound technically impressive, but if done right it could mean a big price advantage for small satellite launches.

If light rocket reuse is as difficult as it was for SpaceX’s heavy rockets, then we might again be seeing one company push all others aside.  But if it’s much easier, as I hope it can be, then several outfits might do it and competition could remain wide open, while bringing prices way down for small customers.  Solid-fuel rockets might become obsolete for commercial launches, because there’s no way to make them cheaper.

The one company that could easily and quickly bring full-blown modern reusability to the small launch business is Blue Origin.  They already have, in the New Shepard, a reusable booster stage of about the right size; all they need to do is create a second stage for it.

 

May 10, 2018

if the solar system fit in a stadium…

Filed under: Hobbyism and Nerdry,science! — Supersonic Man @ 12:00 pm

(I wrote a post about this a few years ago somewhere else, but now I can’t find it, so I am redoing it here, and expanding it.)

How big is the Solar System?

Let’s start by assuming that we have some general idea of how big the Earth is.  If we fly from coast to coast in the United States, we’ve gone one eighth of the way around it.  A long day of driving in a car, say 500 miles, goes about one fiftieth of the way around.  So the Earth is very large compared to your local town or neighborhood, but it’s of a scale that can be grasped and managed with common means of travel, such as cars and planes.  Even preagricultural people sometimes traveled and traded over distances of a thousand miles or more, and that’s not tiny compared to the size of the Earth.

The Moon is a good deal smaller than the Earth, but quite far away from it.  It takes well over one second for a beam of light to travel from the Moon to the Earth.  The distance to the Moon is enough to wrap around the Earth nine or ten times (the Moon’s distance varies over that range during each month).  It’s the sort of distance that a junky old car might accumulate on its odometer after twenty or thirty years of driving — over a quarter million miles when the moon is furthest out.  People are capable of traveling such distances over many years, or in just a few days with our most powerful rockets.

To appreciate the scale of the rest of the solar system in comparison to this, let’s imagine a scale model, sized to fit into a big football stadium.  The scale of this model will be 1/100,000,000,000 of life size.

Let’s look at how each part of the solar system would appear at this scale.  The Sun, which hangs over the middle of the fifty yard line, is a bit over half an inch across — about 14 millimeters, to be more exact.  It’s the size of an olive.  Mercury, the innermost planet, has an eccentric elliptical orbit around it which is eighteen inches (46 cm) from the sun at its closest, and twenty-seven and a half inches (70 cm) at its furthest.  The planet itself is a practically invisible speck, only one five hundredth of an inch across, or a twentieth of a millimeter.  Venus, the second planet, circles our olive-sized sun at a distance of about three and a half feet (108 cm), so its orbit crosses the 49 yard line on each side. The size of the planet is about 1/200 inch, or an eighth of a millimeter, a speck which is probably big enough to see if you get close enough.

The Earth’s orbit is found at a distance of a bit under five feet (150 cm) from the sun.  And the orbit of the Moon makes a little circle around the Earth.  The distance from the Moon to the Earth, which in real life is up to a quarter million miles, and is the farthest distance that any human being has ever voyaged, is only about 5/32 of an inch, or 3.9 mm, in this scale model.  The entire circle traveled by the Moon around the Earth is barely half as big across as the Sun is.  It would fit inside a pea.  The distance to the Sun is almost four hundred times as large.  The diameter of the Earth itself in this model is about 1/200 of an inch, the same as Venus, and likewise would be a barely visible speck.  The Moon, being smaller than Mercury, would be very difficult to see.

Mars circles seven and a half feet out (2.3 meters), and is about 1/400 inch or 1/16 of a millimeter across — a dust speck.  The asteroid belt spreads in a hollow disk around the sun, with the bulk of it starting about ten feet out, and then it thins out at a distance of around eighteen feet (3 to 5.5 meters).  None of the individual asteroids are big enough to see.

Jupiter, the largest planet, sits a little over 25 feet (7.8 meters) out from the Sun.  Its orbit crosses past the 42 yard line on each side of midfield.  The planet itself is plenty big enough to be more than a speck: it’s 1.4 millimeters in diameter, or somewhat under one sixteenth of an inch — the diameter of the head of a pin.  If the Sun is an olive, Jupiter might be a large poppyseed, or a small millet grain.  It has a number of moons, the four large ones being Io, Europa, Ganymede, and Callisto.  The orbit of Io sits about 5/32 inch (4 mm) from Jupiter, and the orbit of Callisto is about 3/4 inch (18 mm) out.

Saturn is 46 feet (14 meters) from the sun.  Its orbit crosses the 35 yard line.  It’s smaller than Jupiter, but if you include its rings, it looks bigger.  You might model it with a small flat sesame seed.  Its major moon Titan sits half an inch (12 mm) out from the planet.  Uranus is much further out, 98 feet (30 meters) from the Sun, so it nearly reaches the 17 yard line, and on the sides it spills over the out-of-bounds line into the sidelines.  Its diameter is half a millimeter, so you might represent it with a grain of fine sand.

In this model, the orbit of Neptune, the most remote true planet, has a span that just about reaches the one yard line, but can’t quite reach the goal lines, orbiting 148 feet (45 meters) from the sun.  Its size is about the same as sand-grain Uranus.

From this you can see that the Solar System is very empty.  Besides the olive-sized sun, everything else on the field is just some specks which, all added together, wouldn’t amount to a grain of wheat.

Now the Sun and all the planets pretty much fit onto the playing field, but that’s not the whole Solar System.  Beyond all the planets are a number of icy bodies, large and small.  They constitute a sort of second asteroid belt.  It’s called the Kuyper belt.  Pluto is one of these icy bodies, and it isn’t even the biggest one.  As far as we presently know, it’s the second biggest.

In our scale model, the Kuyper belt fills the rest of the stadium, beyond the playing field.  Pluto is down in a good low seat right near the sidelines, and some of the others are way up in the cheap seats, hundreds of feet from the field.

The light of the Sun doesn’t reach up there very well.  It casts a good bright illumination in midfield, but the goalposts are pretty dim, and in the top row of the seats you can’t see much when you look away from the sun.  If I have this figured correctly, at this scale, it puts out about five thousand watts of light.  But don’t compare that to a 5000 watt lightbulb — your ordinary traditional bulb puts out mostly heat, so the 100 watt lamp in your living room is only emitting about ten watts of actual light, and if you use a modern bulb such as a compact fluorescent, it will say “100 watts” on the box while only actually using about 25 watts.  The Sun puts out at least three quarters of its energy as visible light.  Think of it more as a 5000 watt welder’s arc than a 5000 watt lamp.

One thing this idea of an arc lamp in a football stadium fails to convey is how slow the light is.  You have to remember that the light from our tiny Sun takes minutes to reach Earth just five feet away, hours to reach Neptune, and most of a day to reach the upper seats.  If there were a snail crawling around on the grass, it might well be moving at several times the speed of light.  And the fastest rockets never approach even a thousandth of that speed.  (The fastest moving objects we’ve ever launched into space, or will launch soon, are solar probes that drop inside the orbit of Mercury.  That inward fall can give them a speed dozens of times faster than, say, the Apollo moon rocket.)

There’s more stuff beyond the Kuyper belt, also consisting mainly of icy bodies.  But I don’t really count this as part of the solar system.  This is where long period comets come from (short comets, such as Halley’s, come from the Kuyper belt).  This zone is called the Oort Cloud.  It’s found out in the stadium’s parking lot, and some thin parts of it probably extend out into the surrounding city, perhaps miles from the stadium.  While the Kuyper belt is similar to the asteroid belt in that it mainly lies in the same plane as the orbits of the planets and rotates in the same direction that they do, the Oort cloud is spread in all directions, and appears to have no net orbital direction shared in common among the various objects.  For all we know this spread of icy bodies may extend throughout the space between the stars, and not constitute a part of our own solar system at all, except to the extent that the Sun’s gravity causes a thickening in nearby parts of it.

Speaking of other stars, how far away is the nearest other solar system?  It would be about 250 miles away at this scale… about the distance you might find between your hometown football stadium and that of a rival team in the next state.  For instance, the distance between Cleveland and Cincinnati, or Green Bay and Minneapolis, or Chicago and Detroit.

August 25, 2017

ten percent of our brains

Filed under: Hobbyism and Nerdry,science!,thoughtful handwaving — Supersonic Man @ 9:40 am

If it were really true that we use only ten percent of our brains, then being granted the ability to use all one hundred percent wouldn’t really make a dramatic difference. It would be like comparing a desktop computer from 2017 with one from about 2005. Sure, the new one is better, but definitely not as much better as you’d hope it would be. They still both do basically the same things, and they’re both still probably hampered by running Windows.

I think there’s some metaphorical truth to the idea for a lot of people, though, because if they don’t get a good strong educational start, the majority of people don’t really have any chance of developing the intellectual side of their innate capabilities. I’m pretty convinced that most of the differences we see between people in “intelligence” have nothing to do with one person being born with a better brain than another. If you’re going to develop into a brainiac, you need to start very early and you need support for it, and most people around the world simply never get that opportunity. It’s only when drawing comparisons between people who have had those advantages, and are already part of a privileged minority, that you can even start looking at innate differences in talent.

May 10, 2017

no Apollo

Filed under: Hobbyism and Nerdry,thoughtful handwaving — Supersonic Man @ 9:21 am

If NASA had not been hurried into building the Apollo mission by the “space race” against the USSR, how might we have arrived at the Moon? Space development might have proceeded a good deal more slowly and less expensively, building on the X-15 rocket plane experiments. I think that program would eventually have arrived at something fairly close to the Space Shuttle. If you solve all the problems of the X-15 one by one to make it orbit-worthy, it would have had to be much larger and blunter, because any adequate heat shield is going to be around four inches thick, and that doesn’t scale down for something skinny or pointy. That sounds a lot like the shuttle to me.

So let’s say we were trying to send a mission to the moon using space shuttles. The shuttle itself can’t go there even in you fill the cargo bay with fuel, and that would be wasteful anyway, as you don’t need most of its bulk. So I think the bits that actually go to the moon would be much as they historically were in Apollo: a lunar module, command module, and service module. Why not just stick those into a shuttle bay?

The shuttle’s cargo bay is 60 feet long and 15 feet across, though for a cylindrical cargo the cross section needs to be a bit smaller, as the space isn’t fully round. The mass limit for a flight to low orbit is a hair over 30 English tons, or 27.5 metric tons. (I don’t think any real flight ever exceeded 83% of that capacity.) What can we work out based on these limits?

You can’t fit all three modules into one shuttle-load, but they’ll go in two loads, if you make the lander a bit less broad and gangly. One would be the command module and lunar module, and the service module would be the other. And we might have to trim a bit of weight from the service module, like maybe take out the heavy batteries and put them in the other load. This means the service module would have to be mounted to the command module by shuttle astronauts in space suits, which would be inconvenient, but doable. Alternately, you might cram the three modules into one flight all preassembled, if their fuel were in another. This would mean at least six operations of astronauts pumping dangerous fluids into various tanks spread throughout the modules. It might also mean assembling the lander’s legs from some inconveniently compact from.

Now you need a rocket to send the set toward the moon — one rather like the S-IVB third stage of Apollo, which used the majority of its fuel to lift the three modules out of low orbit and fling them toward the moon. This rocket was a bit too large to fit into a shuttle bay, but we can reduce its size by at least 25%. Its weight is no problem, if it’s empty. But the fuel would take three additional shuttle loads. Historically this rocket weighed 10 metric tons empty, and pushed a 45 ton payload. The required delta-V is 3.1 km/s. It burned around 75 tons of hydrogen and oxygen to accomplish this. It used about 30 tons more to finish lifting Apollo into low orbit around Earth during launch, which would not be needed in this case.

So the mission would require six shuttle launches, starting with one to put up the booster with maybe the first splash of fuel in it, and three more to fill it up. Then the service module would be brought up, and attached to the booster. The command and lunar modules would come up last, along with the astronauts who will ride in them. That last shuttle could stay in orbit for a couple of weeks to await their return.

It might be better to bring the fuel up in the tanks that will be used instead of needing to pump it from one tank to another, so maybe the booster would just be a framework that fuel tanks would be bolted into. Such a framework might be folded smaller for transport. This would require additional assembly in space, possibly employing double digit numbers of shuttle astronauts over several flights.  But if everything were prepared well on the ground, the task should not be difficult or dangerous. And if the orbits were well planned, the booster stage could be recovered into Earth orbit, and either refueled for another mission, or if necessary flown back down for refurbishment. As SpaceX has demonstrated with their Falcon landings, once a booster is detached from its payload and has mostly empty tanks, a small amount of remaining fuel can accomplish quite a lot of maneuvering, so I don’t think it’s implausible that its engine could return it to low orbit with the last of its fuel, especially if it discards some dead weight such as empty tanks.

The command module might not need to splash down into the ocean. But it might still need a heat shield, just to brake in Earth’s atmosphere enough to slow down into an Earth orbit, so a shuttle can pick it up. Or, this somewhat risky air-braking might be avoidable by making the service module larger and giving it more fuel. (Perhaps it also could use bolt-in tanks. Add at least one more fuel-hauling flight to the schedule in this case.) An ocean splashdown might be the emergency backup option if the rendezvous fails.

I’m sure this sounds a lot more awkward and inconvenient than the Apollo’s comparatively simple process of just launching one big rocket, but it would have been vastly less expensive. Most of the parts would be reusable instead of disposable. The only part that absolutely could not be reused is the bottom stage of the lunar module. Apollo cost us at least $20 billion per landing, in today’s money; this would cost perhaps a quarter of that — and I’m sure if we made this a continuing operation, we would have found ways to lower the costs further. Instead of just six trips to the moon, we might have continued doing dozens. We might never have stopped.

However, I do worry that this process might have exposed astronauts to greater risks. Lots of opportunities for something to go wrong up in orbit, and lots more shuttle flights. As we have seen, those shuttles were not the safest things to fly in.

May 5, 2017

makes it easy!

Filed under: Hobbyism and Nerdry,life — Supersonic Man @ 3:08 pm

Whenever someone introduces me to a new software framework which is designed to make things easier, especially one to make visual layout easier, I usually end up wishing they’d left things difficult.  Because the thing about these frameworks is that they impose assumptions and expectations.  As long as you work within those assumptions and expectations, the framework saves a lot of labor.  But as soon as a requirement comes along which makes you step outside of those expectations, the framework stops working with you and starts fighting against you.  You end up expending as much work getting around the framework as on solving the problem.

This is especially relevant when the framework is for visual layout.  Because then, they only keep things easy when you adhere to certain limitations of visual styling, and the only people who understand those limitations are the developers.  Which means you’re fine as long as you’re willing to live with a programmer’s sense of visual style.  These frameworks seem terrific in demos, because the examples always take advantage of their strengths and avoid their weaknesses.  But as soon as you bring in a designer or marketer who understands design but doesn’t know the quirks of the framework, their ideas will immediately push you into fighting the built-in assumptions, and all the benefits of having a simplified labor-saving technology wave goodbye, going out for a beer while you’re stuck with a job which is now more difficult than it would have been with no help.

This has been true since the early days of graphical interfaces, from Visual Basic to Twitter Bootstrap.  The latter is my particular bete-noir at the moment, as we adopted it at my job, had to retrofit parts of our old design to not be broken by it, then started to develop new stuff which used it but also had the retrofitting in place, and of course were immediately hit with design change requests which don’t get along with it.  Even before those requests, we were already in a situation where our own CSS was in a fight with itself, half of it saying “don’t be Bootstrap” and the other half saying “you gotta be Bootstrap”.

In the nonvisual realm, it isn’t necessarily so bad.  Some frameworks actually do make things easier without making you fight them.  It helps if their use is purely for code, so it’s designed by programmers for programmers, with no end users involved.  One good example nowadays is jQuery.  It makes many things easier and almost nothing harder.

And we’ve been using it at work but now the word is we’re going to switch to Angular.  We shall see how that turns out.

April 8, 2017

eight-bit nostalgia

Filed under: fun,Hobbyism and Nerdry — Supersonic Man @ 1:03 pm

There’s a lot of nostalgia out there for the era of eight-bit computers — especially the home-oriented ones from the likes of Commodore and Sinclair and Atari.  And I get why: they were tremendously liberating and empowering to those who had never had access to computing before.  And the BASIC interpreters they all came with were likewise quite empowering to those who hadn’t previously realized that they could write their own programs.

But as someone who was already empowered, I couldn’t stand those crappy toy computers.  They’d run out of bits just when you were at the point where a program was starting to get interesting.  I never owned one.  I didn’t start wanting my own computer until the sixteen bit era.  The first personal computer that actually made me want it was the Apple Lisa, which of course was prohibitively expensive.  The first one I wanted enough to pay hard-earned money for, at a time when I didn’t have much, was the Amiga 1000.

(Last I checked, my Amiga 1000 still runs.  But one of these days the disk drives are going to fail, and any available replacements will be just as old and worn.  Turns out that what a lot of retrocomputing hobbyists do is to use hardware adapters to connect their old disk cables to modern flash-memory drives.  It may be kind of cheating but at least you won’t have range anxiety about how much you dare use it before it breaks.)

To me, the sixteen bit era, and the 32-bit transition following, was the most fun time, when the computers were capable enough to do plenty of cool stuff, but also still innovative and diverse enough to not be all boring and businesslike.

If I were of a mind to recapture any of that fun with modern hardware, it sure doesn’t cost money like it used to: I’d look at, for instance, getting a Pi 3 with Raspbian on it.  You could have a complete Linux system just by velcroing it to the back of a monitor or TV.  But there are even cheaper alternatives: there’s a quite good hacking environment available across all modern platforms, more empowering and ubiquitous than BASIC ever was… in your browser’s javascript.

November 18, 2016

future cars

Filed under: Hobbyism and Nerdry,the future!,thoughtful handwaving — Supersonic Man @ 8:05 pm

A lot of people who talk about the coming future of post-petroleum vehicles like to pooh-pooh the battery electric car, even though it’s the most successful type so far.  They keep insisting that the real future will belong to hydrogen fuel cells or ethanol or something else exotic.

But consider the following vision for a future car:

It’s an affordable compact or midsize, nothing fancy.  The base model comes with an electric motor for each front wheel, and 25 or 30 kilowatt-hours of batteries layered under the floor.  This arrangement keeps the powertrain out of the way, so it can have a trunk at both ends, like a Tesla.  Its range is at most a hundred miles, so it’s fine for commuting and shopping and local excursions, but very inconvenient for a road trip.

Most people accustomed to gasoline cars would find this disappointing.  But consider the upgrades you could buy for it.  If you want sure-footedness in snow, or more performance, add a pair of rear motors.  (They would be smaller than the front ones, unless you’re doing some aggressive hot-rodding.)  If you want longer range, you could have a second battery pack in place of your front trunk.  And… if you want to drive everywhere and refuel with gasoline, you could replace that front trunk or second battery with a small gasoline engine and a generator.  It would be no bigger than a motorcycle engine, because it would only need to produce twenty to thirty horsepower to keep your batteries from draining while cruising down a highway.  Ideally it would be a turbine rather than a piston engine, as it would only run at one speed.

Or if gasoline goes out of fashion, you could use that space for a fuel cell and a hydrogen tank.  Again, it would produce only a steady twenty or thirty horsepower.  Or there could eventually be other alternatives not well known today, such as liquid-fueled batteries which you refill with exotic ion solutions, or metal-air cells fueled with pellets of zinc or aluminum.

These would not have to be options you choose when buying the car, but could just as easily be aftermarket modifications.  They simply bolt in!  Anyone with a hoist could swap them in minutes, because the only connections needed are electrical, not mechanical.  Even the front trunk would just be a bolted-in tub.  With a good design, these power options might be interchangeable easily enough that people could just rent such an add-on as needed, rather than buying it.  It might be cheaper than, say, renting another car for a vacation trip.

Another option might be to install stuff from below.  There have been plans to make a network of stations where a machine just unclips your empty battery and slots in a full one, from underneath.  With forethought, this car could be made compatible with such a system.

The point is, once you have the basic platform of a battery-electric car, it can be cheaply adapted to run on any power source.  You could run it with coal, or with thorium, if you’re crazy enough.  Whatever becomes the most economical and abundant power storage medium of the future, your existing car can take it onboard.  All you need is to make sure it has some unused room under the hood.

And the best part?  Even if you don’t add anything, you still have a plug-in car that’s perfectly okay for most everyday uses.  In fact, I suspect a lot of people might come to prefer the car with no add-on, because it’s lighter and quicker and more efficient and cheaper that way, and it has two trunks.

November 7, 2016

enduring entertainment franchises

Filed under: fun,Hobbyism and Nerdry — Supersonic Man @ 6:48 pm

What are the longest-lasting, most prolific, most enduring entertainment franchises? When it comes to movies, there are two big ones which usually get mentioned above all others: Godzilla, and James Bond. If you include the combination of movies and TV, Star Trek is hard to beat. But these are only the well-known internationally popular ones. If you look at more obscure serieses that aren’t well known outside of their countries of origin, there are many which, for sheer quantity, utterly blow away those big names.

Here are some examples:

franchise origin years films genre
Hopalong Cassidy USA 1935-1948 66 western
The Durango Kid USA 1940-1952 64 western
El Santo Mexico 1958-1982 52 luchador
The Bowery Boys USA 1946-1958 48 comedy
Tora-san Japan 1969-1995 48 romantic comedy
Charlie Chan USA 1926-1949 47 mystery

This list gets plenty longer if you start counting Japanese TV material repackaged as films, in which case Ultraman and Super Sentai are both formidable. Perry Mason and Scooby-Doo are also substantial.

Things get muddier if you look at public-domain characters who have been the subject of different serieses of films made by independent groups. Some characters who have large numbers of films of independent origin include Sherlock Holmes, Tarzan, Dracula, Frankenstein, and Hercules. Two characters which may be a bit more unified in their origin, and more plausible as having their films constitute a single franchise, include Maciste (Italy) and Wong Fei-hung (China).

But the picture brightens up if you look at franchises which include the longest span of years. Then the mass-produced comedies and westerns centered around particular actors mostly drop away. The most enduring I can find by this measure are:

Godzilla Japan monster 62 years and counting
Perry Mason USA mystery 61 years including TV movies
James Bond UK spy 54 years and counting
Doctor Who UK SF 53 years on TV, and counting
Ultraman Japan SF/kids 50 years on TV with spinoff films, and counting
Star Trek USA SF 50 years on TV, 37 on film, and counting
Zatoichi Japan samurai 48 years
Bulldog Drummond UK/USA action 44 years
Mil Máscaras Mexico luchador 44 years
Looney Tunes USA comedy 41 years and counting, without including shorts
Super Sentai Japan SF/kids 41 years on TV with spinoff films, and counting
Apartment Wife Japan erotica 40 years
Star Wars USA SF 39 years and counting
The Cisco Kid USA western 36 years, then rebooted in 1994 after 44 years off

But these all dwindle into insignificance if you count the short cartoons of characters like Bugs Bunny and Mickey Mouse. I have no doubt that those guys will hit the century mark in due time… though the effects of their early works going into the public domain (if lobbyists ever even allow that to happen) may be difficult to estimate.

October 26, 2016

the popularity of football

Filed under: fun,Hobbyism and Nerdry — Supersonic Man @ 1:09 pm

Why is gridiron football so much more popular than other sports to watch on American TV?  I think it’s because the sport excels at creating drama.  In almost no other sport I can name does a game-changing score typically come about only as a result of many minutes of effort, in which a mishap at any point can mean it was all for nothing.  In sports like baseball or soccer or hockey, big scores come with very little warning, and in sports like basketball or tennis or golf or volleyball, there are no really big moments because each individual score is small and only the accumulation of dozens of scoring moments can create a win.

There are certain sports which are very popular despite being poor at drama in this sense.  Auto racing has even more fans than football, and winning at that involves very little drama — it’s an extremely incremental process to work one’s way forward through the field. To win at bicycle racing is much more dramatic than in any motorsport, because the athletes have to make bursts of intense effort at strategic moments.  But on the other hand, losing at auto racing can be very dramatic indeed.  Maybe it’s true that many fans watch it just for the crashes.

Soccer is the real puzzle. Why is it the most popular sport in Europe, South America, and Africa?  It’s fun to play but I don’t see how it’s fun to watch.  Scores can be very rare, and you may have to watch an hour or more of nothing before seeing a big moment, and that moment comes with little warning. Then if they go to penalty kicks, it’s an anticlimax that makes the entire game pointless. (They should widen the goals and make the game higher scoring.)

Actually, I can think of one other athletic endeavor which can offer the same kind of drama that gridiron football does: the fighting sports. Boxing, kickboxing, wrestling, judo, MMA… no wonder the UFC has grown so rapidly. Except sumo wrestling, which is usually over in seconds. That’s another one which is a bit inexplicable in its popularity.

One sport that might be kind of good at drama is cricket — it sure ought to be better than baseball, from what I understand of the rules. Unfortunately a cricket test is really really long.

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