He recommends What Made Apollo a Success?; NASA document SP 287. I haven't read much of it yet.
The rabbit hole that led me to that was this video he made about progress in learning how the flagellum motor works. It's pretty spectacular--a motor made out of proteins.
We had an overhead tour of the training area. One section of the floor had gratifyingly cluttered benches and desks, but quite a bit of the area’s desks were clean. The spiel of the guide on the tram included the cheerful assertion that the goal was to have a woman person of color on the Moon.
NASA has a bit of a history of trumpeting its "firsts", no matter the details or the significance, so this kind of foolishness has some precedent. But in an era of greater budget squeezes and no great obvious public enthusiasm for the project (or, I'm afraid, clear science or exploration objectives), it seems remarkably stupid to advertise a science/technology project as a social engineering project. The people most interested in "diversity and reparations quotas" would find this a rather inefficient use of money–much better if the money went to projects easier for them to govern.
On the brighter side, there must have been about 400 youngsters there from schools in Texas and several nations south of the border, in brightly color-coded shirts, apparently having a blast. The James Webb lecture was a LCD talk, but with some gorgeous before and after photos. There were lots of hands-on things for the kids, and some of the grownups, and tons of artifacts.
One thing they can do better is the signage. What’s there is OK, but if, for example, alongside the "this is a rocket nozzle from a Saturn V" they had a second poster with a line drawing of the nozzle with important parts labeled, that would satisfy the “general interest” people, but also give more explanation for those who are curious how the thing actually worked. (They often has a provenance explanation.)
Come to think of it, a display of how a rocket motor works is something I didn’t see there. It would best be shown with an animation–several stations for the different kinds of rocket. Maybe I just missed that section–it’s a large place. "How a simple rocket works" could be another display–like a water rocket. It might be too mechanically complex to be a reliable exhibit, though. But…
You’d need a clear plastic rocket (replaced regularly thanks to fatigue), captive to a guide rod. (Or maybe inside a clear pipe? Wear would make the pipe less than transparent after a while). At the bottom something presses it down (a hold-down) onto a plug that corks the bottom of the rocket. Through the plug run two tubes, one long and reaching almost to the top of the inside of the rocket (for air), and the other just inside the bottom (for water). Open the air valve to let air escape, and force water in at the bottom. Then shut the water valve, and force air in until the rocket is pressurized. Release the hold-down, and the air forces the water out and the rocket flies up to the top of the exhibit.
The constraining device would wear (or the rocket plastic distort), and eventually the rocket wouldn’t fall exactly back down where it ought to–so you’d need some guides at the bottom of the system to encourage the rocket to land properly. And some sensors so you don’t have to rely on timing to bring the hold-down into action (suppose wear on the constraining tube makes the rocket fall too slowly). And if this can be cycled once a minute, that’s about 600 launches a day–which is likely beyond the endurance of the toy models. NASA has bunches of engineers–or used to, anyway--so this should be solvable.
Another thing that cried out for explanation was why the instrument panel control switches had guards around them. Adults can guess, if they didn’t know already, but a sentence to explain it to the kids would be nice.
Also, a cartoon of what banks of instrument switches were for what would be nice for adults too. When you can’t read the labels it looks like this.
The atmosphere was upbeat–no mentions of why things failed when they failed, unless it was accompanied by a description of how they managed to fix it (e.g. the solar panel on Skylab, or the CO2 scrubber on Apollo 13.
I’m glad we went.
“Statistics show that all-woman groups are far more likely to choose non-confrontational approaches to solve interpersonal problems, and most definitely are more likely to deal with a situation without resorting to violence, which could be a big problem on a Mars journey, where the crew must live in close quarters for 2-3 years,” Landis wrote. “Numerous sociological studies have shown that women, in general, are more cooperative, and less given to hierarchical social structures.”
I assume that one vets the team members and tests the team to make sure they work together well.
All male expeditions, at least those that demand a lot of physical effort, are known to work successfully: until they don't.
But I seem to remember reading (I obviously wasn't involved) about bitter jockeying for status among junior high and high school girls. It isn't obvious that an all-women crew will be more peaceful. Less violent--probably, though catfights are not uncommon in the high schools. But pathologies ("I'm not talking to her!") could be just as problematic.
I don't think there's a magic bullet for staffing. For a voyage to Mars you want methodical risk-takers who respect each other.
The article on SpinLaunch--spinup to orbit--referenced Project HARP, which I'd forgotten about. Gerald Bull's idea was to send solid stuff to orbit with a cannon loaded with a rocket. You need the rocket to change the direction of your satellite once you get high enough and maybe get some extra speed as well--otherwise your orbit will intersect the Earth again. It could have worked, though the design would have needed some changes to get different orbit directions. Made of two 16 inch battleship guns, one version sits in Arizona and another in Barbados. They're impressive bits of hardware, though the Barbados one is pretty rusty.
SuperHARP is still active. It uses hydrogen/oxygen for the propellent (with some helium in there too) in a 2-stage push. For the same energy, the hydrogen and helium get higher speeds, which helps getting the maximum speed out of your projectile. They claim greater than Mach 32 for the record so far. "Green Launch estimates the acceleration forces involved will peak at around 30,000 G, and it's got a simple enough test for whether a piece of electronics can withstand that sort of shunt: sticking the component to a golf ball with epoxy and whacking it with a three wood."
SpinLaunch sounds interesting too, though it has its own problems--the jolt the bearing will take when the rocket is released, for example.
I'd bet there's some advantage to launching from a nice tall mountain--less atmosphere to go through.
Never mind the desperate scratching about for newsworthy activities; think about that space suit issue. It turns out to be just a symptom.
Did you miss this story too? A space suit almost drowned an astronaut back in 2014. Once back inside the airlock, Parmitano and the other space station crewmembers found that about 1.5 liters of water filled the helmet.
The space suits are kind of old.
A 2017 NASA report on space suits
The spacesuits NASA astronauts currently use on the International Space Station (ISS or Station) – known as Extravehicular Mobility Units (EMU) – were developed more than 40 years ago and have far outlasted their original 15-year design life.
NASA continues to manage an array of design and health risks associated with the EMUs used by ISS crew. In addition, only 11 of the 18 original EMU Primary Life Support System units – a backpack-like structure that performs a variety of functions required to keep an astronaut alive during a spacewalk – are still in use, raising concerns that the inventory may not be adequate to last through the planned retirement of the ISS.
The Martian rovers lasted well past their promised lifespan (though I understand that the engineers low-balled their lifetime estimates to be on the safe side), but there were plenty of glitches along the way that needed to be fixed remotely. "Hey Dan, can you hang on to the strut for a bit while we download a firmware fix for your propulsion control unit?"
"Besides helping the crew, it’s hoped CIMON’s presence will offer researchers an understanding of the benefits and drawbacks of having an A.I. assistant on board." Umm. I'm not sure how much better this is than having a human on the radio with you.
Christian Karrasch insists there’s nothing to worry about. "He's a friendly guy and he has this hard power-off button."
Diagrams: "That was a quick flight."
Some details at Hackaday, and a followup story about the time crunch at the ISS: "ISS crews are rotated out on a six month schedule because that’s about how long a Soyuz capsule can remain viable in orbit. It has a design life of only 215 days, any longer than that and the vehicle’s corrosive propellants will degrade their tanks."
On the Moon, and presumably any airless body, UV-stimulated emission and re-capture of electrons in the cavities left between dust grains can charge the dust, and the negatively charged particles can be levitated by electrostatic repulsion.
We have recorded micron-sized insulating dust particles jumping to several centimeters high with an initial speed of ~0.6 m/s under ultraviolet illumination or exposure to plasmas, resulting in an equivalent height of ~0.11 m on the lunar surface that is comparable to the height of the so-called lunar horizon glow.
Since there's no reason it should jump straight up, a particle will fall down again some distance from its original location. So dust will spread.
This is only significant in airless regions, so don't blame the state of the bookcase on UV light.
In particular, carbonated options like champagne, beer, or a Tom Collins likely wouldn't be viable.
"Aesthetically, bubbles don't work the same," Stephenson said. "When prepared on Earth, bubbles are more buoyant, and they travel up. In space, there is no up, and they clump in the middle until disturbed. It kind of looks like a congealed mess.”
Beyond looks, the bigger issue would be how those bubbles work within astronauts. On Earth, as Stephenson pointed out, gravity helps keep what we ingest down. Gases then separate and rise, leading to burps. But in space, gases, solids, and liquids can intertwine without gravity to separate them. "You can't burp in space," he said. "Well, you can, but you'd probably throw up at the same time."
A cola would be equally unappetizing.
Yuri Miler introduced the program, then handed off to Hawking, who spoke of using technology to transcend human limitations. Freeman Dyson said the interesting part of space exploration isn’t the planets but the other objects—which is an important point for this project, because the chances of getting close enough to a real live planet to get any info are essentially nil. Druyan started talking about how prescient Sagan was, and I had to be elsewhere (missed Loeb). Jenison had a touch-feely talk about the world learning to work together (I suppose the proper rituals must be done), and Warden spoke of exploring our own solar system first—which is a very good point, and a project that might actually be completed.
You’d have to fire off thousands. When accelerating these things you are essentially balancing a small sail (size not given, but it will be flexible!) on a pillar of light and trying to get it aimed to better than two tenths of a milli-radian—if you want to get as close to the star as Pluto is to the Sun. It sounded a bit like using a shotgun to try to hit the 200 yard bulls-eye. But maybe my intuition is wrong.
They plan to beam back the images captured by the probes. Assuming the sails are still in good enough shape to gather energy from the star, beaming it back seems a little fraught. I’d think you’d need to fire off a cloud of re-transmitters behind them. I don’t have the numbers for signal strength, or for the background rates, so I can’t estimate whether that makes sense or not.
Even if there’s something important to look at, the probes won’t be slowing down to chat. At .2c, they’d cover the distance between the Earth and the Sun in 40 minutes. All decisions have to be made on the spot (9 years to get a reply back from Earth!).
On the other hand, it might be handy to send various kinds of probes through the Solar System on the cheap. True, you won’t get gorgeous pictures, or get anything in orbit, or get anything to land. But getting out where the comets live, if the camera resolution is good enough, might give you enough parallax to spot more of the beasties. There are lots of things one could try.
UPDATE: An official list of issues
Well, not the Columbia itself, but maybe the astronauts? Read the article. My guess--probably not, or not all. The initial planning itself would have taken a day or so, and changes in plans add extra delays. If we'd tried, it would have been one of the great "wing it"s, and it would have seriously pushed the limits of how long the Columbia crew could stay alive.
This week they finally discussed Do the Herschel cold clouds in the Galactic halo embody its dark matter?. I read the article and sensed some plausibility, but I couldn’t tell if the methods the authors were using were appropriate.
The idea is simple: there are clouds of something emitting light at about 250microns wavelength, which implies (very) cold temperatures, in the view when the Herschel-SPIRE system tried to look at the Magellanic Clouds. Careful analysis shows that they're actually in our galaxy, and a study of their angular sizes suggests a simple distribution radius from the center of the galaxy. We haven't seen things like this before because we haven’t had the instruments to look for such cold clouds.
If they are in fact distributed spherically about the galaxy and if the clouds have about 15,000 times the mass of the Sun then the amount of cold matter is enough to account for the previously unseen mass in our galaxy. An astrophysicist almost a hundred years ago predicted that gas clouds would spontaneously tend to break up into clumps of about 40,000 solar masses, which is comparable to what would be needed here. So maybe the missing matter is solved: Do we need dark matter theories?
Well, the devil is in the details. (I thank the Journal Club for the details; I didn't know any of this except that he was guessing about the mass.)
For starters, the Herschel-SPIRE system looked in a few other directions, and at several other wavelengths—and none of that appears here. Maybe it is too early, since it takes time to do the studies, or maybe he wants that study to be an independent analysis
The astute reader will have noticed that the mass is a guess. The equations in the paper have the proper scale factor in there, but that scale factor can be pretty much anything less than 1—there is no proof that the clouds are anything like that massive.
UPDATE from comments:
He figured out what average mass the clouds needed to completely account for missing mass, and called it M (actually with a bar over the top but I can't do that easily in html). Then in the equations describing galactic gravitation he wrote c*M. "c" is the scale factor here. He doesn't know the real mass of the clouds, which I'll call "m". You can always find "c" so that m=cM (c=m/M). That's the scale factor here; instead of using "m" (the real-but-unknown mass) he uses "c*M" (an unknown fraction of his favorite guess for the mass).
We know the clouds aren't going to be more massive than M--by construction that would make the galaxy too massive. So c<=1. And they aren't empty, so c>0. But whether they mass fifteen thousand suns or a sand-box worth isn't obvious. It is legitimate to do such mathematical maneuvering if you're trying to illustrate some important connections. Unfortunately his important connection is purely hypothetical.
Another question that arose was what the clouds are supposed to be made of: cold gas isn’t going to radiate; you need dust.
UPDATE from comments:
One of the profs reminded us that cold gas won't be ionized, and neutral atoms only absorb and radiate in particular characteristic wavelengths. Only much more complicated (dust-sized) particles can radiate in a spectrum when they're that cold.
Another question is when such clouds form. If after the transition from which we get the cosmic microwave background (when the universe cooled enough to turn transparent to light(*)), then there are some technical questions about how uniform the gas can be, since structures are already starting to coalesce.
In the main author's pet theory the Jeans clouds should further condense into clouds with embedded "micro brown dwarfs" of about Earth's mass, consisting of about 14 degree blobs of hydrogen at nearly the triple point (solid, liquid, and gas happily coexisting). (They’d be too small to search for with "microlensing", since the radius at which their gravity would cause interesting curvature of distant stars would actually be inside the liquid blob. So you’d not see any strange "jumps" when a star passed near one.)
The upshot: interesting observation, but the model proposed has problems and isn’t near explaining the missing matter problem.
(*) When you have a dense plasma, light doesn’t go very far. Only when things cool down enough so that nuclei get their full complement of electrons, and neutral atoms form, does light get a chance to shine.
Before the kvetchers start in complaining that this was a dangerous waste of money just to satisfy ego, let me counter-assert that we'd never have gotten anywhere if it weren't for people who wanted to do useless things; things like paddle a log upstream or fiddle with electric tubes that glow in the dark.
Maybe nothing will ever come of learning how to jump from space, but I celebrate the urge to explore the limits. And give a thought for the ones who died trying.
BTW, this isn't quite the same thing as teenagers tightrope walking on a bridge cable. Baumgartner planned.
Pavel Naselsky is quoted as saying "The radiation has a spectrum which has the same form as that of synchrotron emission, which originates from electrons and positrons circulating at high energies around the lines of the Magnetic Field in the center of the galaxy, and I believe that there are quite strong indications that it could come from dark matter." I think he has in the back of his mind the 130GeV spike in the spectrum found by another experiment (but not verified; quite a few groups are looking), because I don't quite see how the Planck results suggest anything like dark matter.
If dark matter could annihilate with other dark matter to produce electrons, you would get a lot of high energy electrons curving in the galactic magnetic field, emitting relatively high energy photons as they go. So they're consistent with one model of dark matter, but that's not exactly evidence.
Something is certainly different about what is going on in the "bubbles", and the paper is worth looking at if only for the pictures of the bubbles above and below the galactic core. I'm afraid my eyes started to glaze over while skimming the discussion of all the different models being compared to the data. That's a vital part of their research, and similar things are critical in my field also, but vital doesn't make it exciting.
FWIW, the primary cosmic ray spectrum looks like 1/E^2.6 at the high end (Auger), so maybe it isn't dark matter but some similar acceleration processes at work. That would get my vote.
In the meantime, we have a shining haze where nobody expected it.
I've wondered what his life was like afterwards. After all, "What do you do for an encore?" I hope he was able to enjoy faithfully doing whatever was needed each day without comparing it to his moment in the limelight.
The stories will say that he'll be remembered forever, but forever is a long time--only One remembers that long, and He has somewhat different standards than we do. We'll do our best, though.
Rest in peace, and may the Lord receive you to himself.
The press release is exasperatingly vague on the details, such as how fast the ions are emitted, whether the polarity is reversed from time to time to avoid static charge buildup(*), and how long the thrusters can currently operate. And the release says things like "The researchers envision a small satellite with several microthrusters, possibly oriented in different directions." "Possibly?" You mean "obviously" Ack. I haven’t been able to get at the conference proceedings for details.
50 microNewtons isn’t a lot, but if you’re patient it can do quite a bit for you. For a 1kg micro-satellite, in a day it would change the speed by 4.3m/sec. In 20 days it could change the orbital speed by 1%, which can make interesting differences in the orbit. Or it could rotate the satellite to a new angle, provided there were counter-thrusters to stop the rotation. See "obviously" above.
Of course sooner or later you run out of fuel, but in the meantime you have an uncomplicated rocket. I look forward to hearing more about that.
(*) "Reverse the polarity" sounds like Star Trek technobabble, but suppose you're firing off the positive ions. Your craft will gain a net negative charge, which has two bad effects: it pulls you backwards towards that positively charged cloud and thus reduces the thrust, and it adds some sideways complications as you travel through the Earth's magnetic field. Neither are huge effects here, but then neither is the thrust. So it would make sense to change the polarity of your needles and eject the negative ions for a while, and use the whole fuel supply. The reports were cagy about the nature of the salt, but probably the negative and positive ions are different enough that you could only optimize for good thrust with one variety and the other wouldn’t be quite as useful.
Being lowered at 2mph by cables from a rocket-levitating platform: I understand the importance of that to preserve the delicate drives (otherwise they have to be much more rugged and heavy), but I can't help feeling that somebody thought it would be really cool to try. First pix
I was glad to find some good news after the evil from Milwaukee last night.
Harrison Schmitt is an adjunct professor at the UW-Madison. (I heard him lecture once on lunar geological history.) Deke Slayton and five other astronauts are from Wisconsin.
But for sheer excitement can you beat a Sputnik crashing into the street? True, the actual event wasn't very alarming--nobody noticed for an hour and when they did they thought the hot object was some slag from a local foundry. I'm trying to imagine the reactions: "Hard hat area: falling spacecraft" or "Reinforced umbrellas for sale."
Odd that I should only learn about this from a BBC article about a claim that one crashed in Scotland too. Next time we go through Manitowoc we'll have to go look.
Never mind that the presence of mine-able quantities of platinum is extremely speculative, and that if they did luck out and bring home enough to pay for the enterprise the price of platinum would plummet. (Platinum was the example around the water cooler.)
Can the lawyers win this one? Nobody can enforce anything in space. Nobody has the reach to do much of anything outside of low Earth orbit. If CocaCola wanted to spray-paint their logo on the Moon (silly idea, most of the time it would be obscured), a minute after liftoff there'd be nothing anybody could do.
Of course lawyers win. Sooner or later you have to come home, and then what happens to your cargo? Your only hope is to land in a compliant little country whose Colonels won't be tempted to take on your security team. Otherwise, meet taxes, import duties, and fines; and maybe revenue-sharing among the space powers.
So never mind the mining--at least for a decade or two. Or three.
What could be done with platforms? What could be done with space platforms that would pay for their construction and maintenance, on a timescale impatient investors can handle?
The problem I see is that almost none of what they can do best would be that marketable on Earth. Science is wonderful, but I have to admit it doesn't make a lot of money right out of the gate. (A few years down the road, or maybe a lot of years down the road, yes.)
If mining runs into jurisdiction problems, and solar concentrators aren't trusted ("What say we tilt this array a tenth of a degree or so?"), and manufacturing delicate items for harsh re-entry isn't quite as economical as it sounded, what have we got left? Tourism? Colonies?
