Did little ISON -- fairly small as comets go -- survive its daring-close passage by the sun. She's already provided lots of valuable science. But will she also give us Earthers a fine eyeball-show in mid-December? As we bite our fingernails, awaiting the re-emergence of Comet ISON, I flip through my old doctoral thesis (on comets!) Meanwhile, have a look at XKCD's terrific cartoon about what comets actually think of the Sun. Folks who want a much more thorough and lovingly detailed (hard science fictional) look at these strange creatures might have a look at Heart of the Comet!
…and ponder how valuable it might be to become a truly spacefaring civilization.
I'm trying to help that happen! By telling good stories set out there. By serving on the advisory board of NASA's Innovative and Advanced Concepts group (NIAC) - meeting in Silicon Valley in February…. and by helping some of the groups mentioned in my previous posting (about personal philanthropy and saving the world!)
...here's a truly excellent editing of my interview about SETI and the Fermi Paradox distills the crucial matters into just over three minutes. Well done, Daily Galaxy.
== Litter the moon with personal spam? ==
The latest worrisome Space Fan Stunt -- the Pocket Spacecraft: Mission to the Moon project lets individuals or groups buy an 80mm diameter, 50um thin disk with hybrid printed electronics bonded on its surface that can do primitive sensing and communications, all of it under a printed image of your grinning face(s). "Additional variations that may fly on the mission include a 34mm diameter Earth Scout, and up to four triangular 8M2 SmartSail Scout panels on the optional solar sail propulsion module." "Explorers who back the project can personalise their own spacecraft by adding a picture and customising the message it transmits using just their web browser."
Why worrisome? Sounds like one more fun outgrowth of the very successful CubeSat program, right? In fact this is part of a trend I'm not particularly fond-of. For-profit groups exploiting space-fans by providing a vicarious -- and scientifically meaningless -- "participatory experience" that ultimately boils down to a kind of subsidized pollution.
Okay. This once isn't so bad. So a hundred silly disks get scattered on the Moon's surface. Far worse are the idiots who have got their mitts on old radio tracking and communications dishes that were paid for with taxpayer funds and that are now obsolete and cheap to acquire… suddenly proclaiming that they will beam forth "messages to ET" on behalf of humanity, for a fee. Either spitting Dorritos ads at Gliese 382, or else jumbles of thousands of "yoohoo shouts" from individual zealots who pay $20 per millisecond of ego-time aimed at a speck -- a stupid stunt, whose small but real potential for endangering humanity the perpetrators blithely ignore. Compared to that, this lunar thing seems pretty harmless.
Still, it is a general phenomenon we should keep an eye on. Right and left-wing nostalgia junkies aren't the only kinds of suckers… I mean eager potential sources of revenue... out there, ready to plonk down cash for intangible participation in a delusion. These "science stunts" show that even on the side of humanity that loves the future, there are still folks with far more zealotry than sense. But did I have to tell you that? Ever been to Comicon? Ever talked to a Star Wars fanatic? Enough said.
Oh, but let me add a coda: here's a Free audio podcast on StarShipSofa of one of my coolest recent stories -- "Mars Opposition" -- in which (alas) folks like me who took part in an earlier stunt… harmlessly "signing" a Mars rover… get what we deserve!
== Cooler space news! ==
"What are your best ideas for creating a NASA human spaceflight program that is sustainable over the next several decades?"
Me? I like the plan to investigate asteroids by dragging small ones to near lunar orbit. It hits the sweet spot of challenging yet do-able, exploring deep-space technologies and methods... while helping new companies investigate possible treasure troves of asteroidal resources. Sure beats returning to the sterile and (currently) useless Moon!
In any case…China plans to launch the Chang'e 3 lunar probe on Monday -- the first time China will attempt to soft-land on the moon, a feat accomplished, so far, only by the U.S. and the former Soviet Union.
U.N. officials announced plans to establish an International Asteroid Warning Group to intercept and divert dangerous asteroids.
Meanwhile, the Hubble Space Telescope will begin peering just past some tight clusters of galaxies, using their gravitational lensing effect to attempt to spot objects ten times fainter or farther away than normally possible.
NASA has outlined a new plan -- K2 -- to resurrect the Kepler Planet hunting Probe -- using solar pressure to stabilize the probe and restore its ability to reliably point toward at distant exoplanets.
NASA‘s Lunar Laser Communication Demonstration (LLCD) has made history using a pulsed laser beam to transmit data over the 239,000 miles between the moon and Earth at a record-breaking download rate of 622 megabits per second (Mbps). That's a huge breakthrough.
Incredibly bright black hole puzzles astronomers.
Researchers have confirmed a suspected dust ring in the orbit of Venus.
NASA contest -- open to high school and college students -- challenges teams to create the next-generation space buggy -- a vehicle capable of exploring the surface of other worlds.
Could we store data for one million to one billion years, using a new storage medium based on tungsten and graphene oxide? The chosen information carrier is a wafer consisting of tungsten encapsulated by silicon nitride. Tungsten was chosen because it can withstand extreme temperatures. A QR code is etched into the tungsten (see picture) and is protected by the nitride.
Amazing: nanoparticles, guided by synthetic DNA to self-assemble into large-scale composite materials.
What happens to the human brain when it slips into unconsciousness? "In terms of brain function, the difference between being conscious and unconscious is a bit like the difference between driving from Los Angeles to New York in a straight line versus having to cover the same route hopping on and off several buses that force you to take a 'zig-zag' route and stop in several places," said lead study author Martin Monti, of UCLA describing functional magnetic resonance imaging (fMRI) studies of this transition.
== And more… ==
A cute summary of Nobelist economist Paul Krugman's theory of interstellar trade.
"A NASA spacecraft has revealed an unprecedented view of Saturn from space, showing the entire gas giant backlit by the sun with several of its moons and all but one of its rings, as Earth, Venus and Mars all appear as pinpricks light in the background."
Both Mars rovers are now climbing features named after my friend, the great planetary scientist and former JPL head, the late Bruce Murray. See images of "Murray Ridge."
A film, Pale Blue Dot -- takes the Kerbal Space Program quasi seriously! Only then it gets elegiacal and beautifully moving.
A cool article about space megastructures contains a nifty animated depiction of a Niven Ringworld.
A cool article about space megastructures contains a nifty animated depiction of a Niven Ringworld.
Okay, them's cool stuffs.
Now back to nail-biting. Come on ISON. You may be little, but you're tough!
Final note: Assuming ISON survives: Skygazers can plan on seeing the comet come Dec 1. "It would be low in the sky early in the morning,...Each day it will go higher in the sky and be visible earlier in the morning, closer to midnight. By the 17th it will be up or around the Big Dipper and should be visible closer to midnight." (ABC NEWS)
RIP Comet ISON:
"Born in a dusty and turbulent environment, comet ISON spent its early years being jostled and struck by siblings both large and small. Surviving a particularly violent first few million years, ISON retreated to the Oort Cloud, where it maintained a largely reclusive existence for nearly four billion years. But around 3-million B.C., a chance encounter with a passing star coerced ISON into undertaking a pioneering career as a Sungrazer. On September 21, 2012, ISON made itself known to us, and allowed us to catalog the most extraordinary part of its spectacular vocational calling.
"Never one to follow convention, ISON lived a dynamic and unpredictable life, alternating between periods of quiet reflection and violent outburst. However, its toughened exterior belied a complex and delicate inner working that only now we are just beginning to understand. In late 2013, Comet ISON demonstrated not only its true beauty but a surprising turn of speed as it reached its career defining moment in the inner solar system. Tragically, on November 28, 2013, ISON's tenacious ambition outweighed its ability, and our shining green candle in the solar wind began to burn out.
"Survived by approximately several trillion siblings, Comet ISON leaves behind an unprecedented legacy for astronomers, and the eternal gratitude of an enthralled global audience. In ISON's memory, donations are encouraged to your local astronomy club, observatory or charity that supports STEM and science outreach programs for children."
"What are your best ideas for creating a NASA human spaceflight program that is sustainable over the next several decades?"
We've talked about this before. I personally think Nasa's asteroid capture and human exploration is little more than a stunt. When a human rendezvous was originally proposed (I went to a talk by Landis at the SETI Institure) it was clear that the goals were to have a destination that was reachable, would test partially closed environment systems, require no hard landing like Mars, and would offer some valued science as well (although we discussed the value of humans vs robots in this regard). The larger context was the idea of having fuel depots for deep space travel, probably on dead comets.
The Nasa proposal eliminates almost all the technical difficulties, albeit with new ones such as asteroid capture. There seems little point in having astronauts clamber over a small, captured rock to play at sample gathering. A robot controlled from earth would be much more sensible, and cheaper.
IMO, the Mars flyby, originally proposed as a private venture but apparently not financiable, would be a better goal. It would emulate Apollo 8, but be far riskier today, which unfortunately makes it a non-starter for a publicly funded agency. I still prefer a target flyby, with enough time (3-6 months) to test new hardware for life support, plus artificial gravity via rotation. The initial tests could be done in LEO and GEO, before doing the voyage.
My guess is that the US will still be doing paper exercises that will never fly when the Chinese accomplish the task.
If the hardware could be made to work, then the follow on goal would be a landing on Phobos or Deimos, with a stay while robots descend to the planet and are controlled remotely from the Martian moon. Some good science could also be obtained by exploring the Phobos/Deimos by human astronauts, including experiments for resource extraction.
To follow up on a next mission. It has now been over 40 years since humans last stepped on the moon. Flight ready rocket technology has pretty much plateaued with LH2/LOX, which is really only suitable for the near earth space. Not surprising since most of our exploitation of space has barely been further than GEO. Deep space missions need much more energy, but nuclear propulsion has gone nowhere in this time. (The moon might be a good place to test such technology).
If we are going to be a space faring species, these are the technology fronts that I believe need to be solved:
1. Low cost access to space. Vehicle reuse is key. Hybrid air breathing/rocket engines are likely part of this solution. RE's Skylon shows the way forward. We need more exploration of approaches.
2. High energy propulsion systems for deep space. Possibly nuclear thermal. Fission fragment rockets may be another if the charged fragments can be controlled.
3. Radiation protection. The current approaches tend to be:
a. don't stay in space long, or
b. bury yourself behind shielding.
Both make little sense for deep space missions. Before we resort to trying to genetically engineer our potential astronauts (which seems highly immoral to me), we should be looking at exploiting the new understanding of cancers and the new experimental treatments being reported as a way to solve this problem. GCRs and the solar wind will be omnipresent and a fact of life for anyone exploring or living in space.
4. Closed system life support. To me this is the least important technology, especially if fast flights can be realized with associated large payloads. However we will want this approach for establishing outposts. A part of this may be food processing techniques, e.g. making algae palatable and be more like conventional foods. In addition, I would add the idea of artificial g to make the conditions be more like that life needs, rather than trying to have life adapt to micro-g, plus all the associated problems zero-g makes for a host of processes.
Hey Alex, interesting points.
As a metallurgical engineer who has worked in mining, I am completely unconvinced that there is any economic value whatsoever in capturing an asteroid in the foreseeable future. We had a jolly debate about it a while back here, but my points boil down to (pun intended):
*It seems to me unlikely there is any mechanism for natural mineral concentration on most asteroids, so there is no ore to mine, regardless of higher average concentrations of useful elements.
*Even if you grab a metal asteroid, the steel you would be making would be terrible without significant refining. I am not convinced this would make economic sense. Steel doesn't do well in vacuum anyway. What you really want is titanium, beryllium or aluminum (see point 1).
*Even if space miners make a chunk of pure iridium, I think it is unlikely there is a way to get it to the only economy (currently) in the Solar System where you could sell it. I concede there is a slim chance for a momentum transferring sky hook, maybe using the tailings as a momentum source, but it sure sounds unlikely and even if it works, very expensive. If it does work, the law of supply and demand will make sure profits are minimal, probably negative for any metal I can think of. A possible out here is for some scarce metal that is useful but has become economically unviable to mine on Earth. (Note that rare earths are not rare.)
I just see no way to make space mining pay in the absence of an economy in space.
Chicken, meet egg.
"What are your best ideas for creating a NASA human spaceflight program that is sustainable over the next several decades?"
We need to stop fantasising about building pyramids and buy some camels and carts.
The manned asteroid mission idea is cute, but it immediately contracted to the smallest program possible. It would not built new capability and would just be a really, really, really expensive way to a robotic sample-return mission in order to give the pointless Really Big Rocket (tm) a job.
Instead I'd like to see a Grand/Urban Challenge style series of million dollar prizes to get private companies to develop a varied and competing set of probes/rovers/landers cores. And, separately, standard tools and instruments all based around a common plug'n'play design shared with the probes/rovers/landers. Then fund a bunch of very low cost missions to... well, anywhere and everything... by ordering the appropriate core (probe/rover/lander) and an appropriate set of now off-the-shelf instruments. The idea being to put technology on the shelf in order to buy it off the shelf. Missions would start simple, and often fail, allowing parts-suppliers to iron out the bugs in their designs. As the parts get more reliable, the missions get more complex/challenging. Incremental development instead of reinventing the wheel for nearly every single program. (I want to see families of probes numbered into double figures again.) If missions cost more than $100m for the hardware, you've overstepped and need to simplify, or even go back to the challenge/prize stage.
In addition, a COTS style program (multiple competing vendors and designs, fixed contracts, payment on delivery of milestones) to develop satellite refueling. Then to develop orbital depots and delivery systems; starting with hydrazine, then cryo-Xenon, then cryo-LOx and methane dual-fuel, then cryo-LOx/cryo-H2 dual-fuel. (You'll need a standard set of target satellites... but remember that off the shelf technology we put on the shelf?) Then to develop a refuelable in-orbit tug capable of carrying a payload from LEO to GEO and returning, being refueled, and repeating the feat.
Somewhere in there, the reduced cost and increased capability might permit an expansion of the manned program outside of LEO. But not just a single magic target. Back To The Moon! No, On To Mars! No, Asteroid Mining! Instead an incremental program to gradually spiral outwards in stages, building the commercial supply lines for each stage, staying just one small step (ha ha) ahead of private manned flights, and semi-commercial markets. The only goal is to get the price of delivering and supporting humans low enough that it'll actually be cheaper to send a human than to send a robot. (Or to send a human to fix the robot.)
[Aside: I don't want humans on Mars at all until we've fully eliminate the possibility of native life. In case some variant of panspermia is true, which means (modern) cross contamination will make it extremely difficult (and controversial) to identify Martian life. While the same is true of comets and (wet) asteroids, there are many more untouched bodies if we stink up the first few. Mars, Europa, Titan are special and need to be deeply bio-protected until we can rule out at least Earth-like (DNA/RNA-based) life.]
"I just see no way to make space mining pay in the absence of an economy in space. Chicken, meet egg."
I agree with this. The "proto-avis", IMO, is water for fuel/air/water (and perhaps bulk-shielding) for in-space use. Obviously, initially, NASA is a necessary anchor client. But if we seed the development of low(ish) cost, private space stations, then there may be a purely private market developed. Provided you can get the price in orbit below that of launch-costs, you will own that market. That may open up markets for simple secondary materials (extruded metal trusses, etc). And eventually, your platinum-group rich "waste" can be delivered to Earth, essentially for free, as a side product of the other processing and transport. (It might not work, it might work but not follow that path, but it suggests that an incremental evolutionary model that gets us to the chicken is at least possible.)
Geneticists not only confirmed that humans interbred with Neanderthals, but that H.Denisova inter-bred with a new/unknown homo species.
Interesting comment in the article from a researcher: " "What it begins to suggest is that we're looking at a 'Lord of the Rings'-type world — that there were many hominid populations," said Mark Thomas, evolutionary geneticist at University College London. " [A better analogy might be the Ringworld sequels.]
Makes me wonder if some of our legends and fairy tails stem from the barest fragments of tales handed down from our interaction with other homo species. Including many sub-species that left no fossil evidence. (I mean, look at the racial diversity of homo sapiens in just 30-50 thousand years. How much variation was there in the 1.8 million years since the first hominins walked out of Africa?
And an interesting observation on the architects (or architechs) of healthcare-gov: http://www.slate.com/blogs/weigel/2013/11/27/what_did_cgi_federal_get_wrong_with_healthcare_gov.html
Seems the CEO had fairly weird management ideas that likely led directly to his companies failure to properly develop or test the heathcare.gov back-end. (Interestingly, the front end was designed by another company, and was slightly more successful.)
Vermont, home of another failed CGI project, just decided to double CGI's contract payment to fix the failed project. So at least you know they are being punished for their incompetence...
"In terms of brain function, the difference between being conscious and unconscious is a bit like the difference between driving from Los Angeles to New York in a straight line versus having to cover the same route hopping on and off several buses that force you to take a 'zig-zag' route and stop in several places,"
And yet, many Singularitarians seem to be under the impression that the brain shuts down completely when you sleep. Thus they claim that destructive brain uploading would be no different from falling asleep.
Wait a moment. If there's a ring of dust in the orbital path of Venus, does that mean Venus has not cleared out its orbital path and is thus not a planet?
We're down to 7!
Makes me wonder if some of our legends and fairy tails stem from the barest fragments of tales handed down from our interaction with other homo species.
Crichton covered this in 'Eaters of the Dead'. A re-telling of the Beowulf legend. 'Grendel' was portrayed as a remnant tribe of feisty neanderthals.
If there's a ring of planet disqualifying dust around Venus, then why not Earth? (IAU does a hurried Gonski-flip on planetary definitions)
Singularitarians seem to be under the impression that the brain shuts down completely when you sleep
Do you have a reference for this?
destructive brain uploading would be no different from falling asleep
It obviously is different, but perceptually there should be no obvious difference between becoming unconscious and either reawakening normally, or as an uploaded mind. We now have shown which parts of the brain appear to "shut down" when consciousness is lost. Your consciousness then "reboots" on awakening.
There are a number of ways that you could recreate the mind and unless there is some magic happening I see no conceptual reason to discount mind uploading with sufficiently advanced technology.
Paul451, I actually think it is more likely that we will "drill a hole through space" by building a space station and start mining solar power and shipping it back to Earth than we will ship anything material to Earth. (Reference is from the Stanford Torus project...)
Honestly, you won't have any decent ores from almost any asteroid you can divert. It has to be, or have been on, one large enough for some sort of differentiation to have occurred. Given that we don't know of any asteroid with a water history, mineral concentration would have to have been of the igneous variety, so hot enough for long enough to concentrate some mineral. Easier by far to find such veins on Earth.
Maybe volatiles, and only then if you already have a functioning economy on orbit. ("On orbit" is what it is really called.)
So from egg to chicken in my head is: power sats to space habs to bulk shielding and volatile processing to (maaaayyyyybe) metal asteroid mining for metal that stays out of a gravity well.
I think you guys under estimate the potential for melt-fractionating ores using solar mirrors. There are some clever possibilities. But yes, it will take a while. The first asteroidal resource is water. Bag it and focus a lesser mirror. Collect the evaporating water. Extremely valuable.
Dr. Brin, it doesn't matter what or how you heat if you don't have concentrated ore. Undifferentiated meteoroid, even if it has more iridium, aluminum, titanium, or whatever on average than the Earth, is still just dirt. Even on Earth we can't use many potential sources of valuable metals. Aluminum is the most abundant metal in Earth's crust, but we can only make it from one ore that has been leech soaked for millennia in the tropics. Titanium is all around us, but only a particular type of beach sand feeds the process that makes the metal. I'd love to see the process whereby regolith is vacuum fractionated into anything remotely useful.
I don't know if Vesta or something like that might have ores - that is too foreign to my understanding of geology. And of course there might be chunks of differentiated something knocked off of one of the larger bodies, but I would guess that the vast majority of meteoroids would be totally useless. (I think Heinlein might have understood this - I recall he wrote about "core material" asteroids, the core of a smashed up planet that made the asteroid field that could be mined. Remember he had mining experience too.)
And to get water or other volatiles, we are likely going to have to go beyond the asteroid belt, or lasso a passing comet.
I wouldn't bet on asteroid mining. I think the way to the stars lies through energy, not mining asteroids.
If there is human habitation on the Moon, I *would* bet on mining there, (at lest water) though I don't imagine it would make economic sense to try to send it anywhere else.
First off, asteroids are probably best used for structures in space. (Cost of transporting into space would make some processes worthwhile)
I wonder if using plants to gather the ores would be viable?
I saw the notion of solar on the Moon and did an eye-roll, but I think you could set up pretty useful arrays in the stratosphere.
I am much less sure that mining asteroids is a no go
The metal ones - going from meteorites are not just good grade ore
"The chemical composition is dominated by the elements Fe, Ni and Co, which make up more than 95%. Ni is always present; the concentration is nearly always higher than 5% and may be as high as about 25%"
Iron, Nickel and Cobalt make up over 95%!!!
That is not ore that is metal! - the Inuit used shards of meteoric iron before contact with Europeans
If we end up with a significant amount in orbit then lumps can be landed for very little money - the main issue would be carving and foaming the raw material
Nickel costs ~ $13/Kg
a ten meter cube of metal before foaming would weigh ~ 7,000 tonnes
And contain from 4 - $20 Million of Nickel
Not sure if foaming would be required - there may be a happy size where the re-entry losses and the final velocity mean a solid lump can be hard landed without excessive losses
Too small - loses too much from re-entry
Too big hits too hard and splashes
Historical iron meteorites - such as the one brought back by Captain Peary - show that multi-tonne lumps land without either burying themselves too deep or spattering
The first asteroidal resource is water
Absolutely. And Ceres may be the equivalent of the Middle East in space, although there are probably better choices with lower delta v to mine.
What is needed is an efficient way to move that water to Earth orbit without incurring loss of most of the water mass as propellant.
Has anyone considered trying experiments on the ISS to see how best to extract water from a comet or icy moon?
SteveO your clearly experienced skepticism is welcome! But bear in mind that most asteroids come from a smashed protoplanet that had already undergone extensive fractionation and settling. I am not sure how good an analogue "dirt" is. Many asteroids and meteoroids come from the wholly metal core of that pro to-=planet.
STeveO why don't you get someone to buy you MINING THE SKY by Lewis for the holidays. You seem the best equipped among us to read it and study the topic and report back here. Hm? ;-)
Volatiles are present on many bodies we can reach in reasonable amounts of time. Higher concentrations require less capital investment in the equipment to cook them out of the rocks, but it all comes down to cooking. From a commercial perspective, volatiles are where the first money will be made and they are probably the simplest to extract.
I don't mind the space junk on the Moon.... as long as it actually lands on the Moon. If th stuff misses and winds up floating around in orbit it is a completely different problem worthy of demanding insurance policies in the flight permitting process.
The most valuable resource in the solar system to us right now is the water at the lunar south pole.
Humans are proving to be unsuited to long duration zero-g. Mining asteroids implies a substantial human presence in zero-g, which is a nonstarter. Until we lick the bone-density loss problem an the radiation problem, or we can teleoperate the robotics well enough to not need a physical human presence, asteroid mining is a non-starter.
Water is the most valuable element because it is breathing gas, rocket fuel, coolant, radiation shielding, potable, and required for agriculture. It is the most concentrated harvestable resource in the zone we can reach with our technology.
The water on the south lunar pole is the water we need to be extracting. We can work on the moon and its gravity will offset the bone density loss problem. We can dig under the lunar surface for radiation shielding. The moon's gravity is low enough that we can export lunar water to other locations on the moon, to anywhere in the Earth-Moon system, or to Earth orbit using the water itself as propellent in the form of liquid oxygen/liquid hydrogen.
Not only does the lunar south pole have the unique attributes of Shackleton Crater which is perpetually in shade, it also has the unique attributes of the Mountains of the Dawn, which are perpetually in sunlight. We can derive all the power we need to operate on the moon from solar - and we might even be able to make solar panels from local materials.
Water from the moon can be used as propellent for any exploration missions we want to undertake outside the Earth-Moon system. Fueling a trip to Mars with Moon water will be vastly cheaper than trying to fuel it from the surface of the Earth. In fact we should send the water needed to return from Mars to Mars from the moon as well, meaning the size of the ship and the amount of fuel needed to make the trip would be substantially reduced.
Once we have a steady supply of Moon water we can also talk about extracting Helium-3 from the regolith, mining metals and other useful minerals and building a linear accelerator on the Moon to deliver those materials where needed, and constructing an Arecibo-style radio telescope on the Lunar farside.
It is virtually certain this will happen. The only question is if the extractors will be the United States, the Russians, the Chinese or the Indians.
Unlock the water, unlock the riches of intersystem space.
What we need is a "War on Asteroids".
War is utterly inefficient economically, but works wonderfully to concentrate resources toward a goal, even if the goal is obviously unachievable after decades of trying. Nearly all major progress in space technology came from war, hot or cold - commercial efforts have mostly reused and slightly embellished on that progress.
When a decent sized meteor takes out a major city, we'll see the WoA kicked off. Funding will flow, because after all SOMEONE has to think of the children. And that will boost humankind into space, one way or another.
"IMO, the Mars flyby... would be a better goal."
So what would the fly-by mission achieve, beyond the value of testing done in LEO or GEO?
Once you've proven the systems that can get people to Mars and back, why not go for Mars orbit and do something useful? The rocket systems needed to enter and leave orbit could also be tested near Earth.
About the only benefit I've been able to come up with for a Mars fly-by mission is that it saves some money - at the cost of achieving absolutely nothing beyond the near Earth testing. But if saving money is the goal, just do the near-Earth systems testing and drop the actual fly-by.
The biggest breakthrough needed for human conquest and colonization of space...
...is the conquest of cancer.
So long as people fear getting cancer, few will want to live off Earth, let alone plan to raise families there.
For every other major issue, we've got or can very quickly produce reasonably good (though not cheap) technological solutions.
True, we do have a technical solution for radiation-induced cancer - burying ourselves alive and using tele-operated robots for nearly everything outside.
But that's very expensive for transport (tons of excess mass per person on every vehicle), and unattractive for potential colonists.
Space colonization has to be attractive - lively and exciting, rather than deadly and dull - or only a fanatical (delusional) few will go.
Asteroid mining does not necessarily imply a human presence and that is especially true of volatiles extraction. You need a scooper of some sort and a cooking oven. Another option is a hollow-core harpoon and some gas you can heat and inject. What would actually work probably depends on the site and a bit of experimentation, but adding a human on-site is probably not a good idea.
I suspect the lunar water WILL be the first mined, though. The time cost of money is enough to discourage asteroids as a first attempt. We will see. eventually.
Why go for Ni-Fe lumps, when the money is in volatiles? Go for carbonaceous chondrite asteroids. They are full of CAIs (calcium-aluminum inclusions) and volatiles, water included among other organics. Many are friable and easily broken down. If you can get some large solar concentrating mirrors out there, turning a CC asteroid into a warehouse of useful materials should be relatively(!) easy.
dychre: ochre, +1
I'm not sure why you talk of "ores".
Metallic asteroids are primarily composed of elemental metals. They've already been differentiated. Approx 80% metallic iron, 20% other metals. And much of the metal on even non-metallic asteroids is impact debris from metallic asteroids. (Likewise the easiest metal to access on the moon (or Mars) will initially be metal "dust" from impacts. On the moon, about 1% of the surface material. Collected from regolith with a magnet.)
You're are picturing undifferentiated rock on Earth. Something like basalt. That's wrong. (I assume there's analogues on basalt up there, but no one is talking about using them for anything (except maybe basalt fibre reinforcing.))
"the moon and its gravity will offset the bone density loss problem"
Actually we don't know that. We have no idea of the shape of the curve between 0 and 1g. And if 1/6th isn't enough, then we'd need to have centrifuge habitats, which are likely to be more difficult on the surface than in space.
(In a larger asteroid, you can even tunnel out a ring a few hundred metres in diameter, install rails, and run modules around for gravity. You don't need a hub, although you'll need a second rail to run the airlock-tram alongside. IIRC the last time I worked it out, a 200m wide ring would need a velocity of less than 100kmh. With a larger ring and lots of spare power, you could fill the tunnel with air and then the habs wouldn't have to be air-tight. You could build a ring on the surface, but having it inside the asteroid gives you maximum shielding from radiation and impact. Combine something like this with a bi-conic-type cycler orbit, and you'd have permanent ships-cum-bases cycling permanently between Earth and your target (Mars/Jupiter/asteroid-belt). Short shuttle flight to meet the passing cycler-base, comfortable trip to the target with fuel/air/water/gravity/shielding provided (and probably greenhouses, so food), then a short (refuelled) shuttle hop into the target orbit when you arrive.)
We don't know the composition of water (if any) at the lunar poles, nor in "wet" asteroids. We don't know what comet remnants (burned out comets, which makes up a decent proportion of NEOs, IIRC) are like, particularly their interiors. We don't know the number of solid, semi-solid and rubble-pile asteroids. We know almost nothing.
That was why I suggested that to get the most bang-for-space-buck out of the next decade, NASA should fund the development of low cost standardised hardware which can be then bought off-the-shelf for hundreds of extremely low cost missions to any target of interest. Instead of spending $2.5b on a one-off Mars rovers, or $9b on a one-off single telescope, or $2.7b/yr on a Big Rocket without a mission.
"So what would the fly-by mission achieve, beyond the value of testing done in LEO or GEO?"
Don't dismiss tokens. Sometimes you have to show people that something is actually possible before they will believe you.
Volatiles are the first obvious market. Metallics are assumed to come later. Interestingly, wet C-type asteroids will also have impact debris from M-type impacts, which can be extracted by magnets. (Would that all ore separation were so simple.) So we'll have plenty of material to experiment with, while we are selling water. Once that early material creates a market for metals, it's off to the M-types.
"So what would the fly-by mission achieve, beyond the value of testing done in LEO or GEO?"
That statement suggests that you are too young to remember Apollo 8. It was a major event, only exceeded by the actual moon landing by Apollo 11.
Surely Lindbergh could just have flown in circles until he achieved the distance across the Atlantic to prove it could be done. *smile*
We don't know the composition of water (if any) at the lunar poles
Indeed. There is still a lot of argument about this. If water ice is a very low percentage of the regolith it may be quite costly to extract. Worth it for a lunar colony, but perhaps not elsewhere.
Asteroid mining does not necessarily imply a human presence
I agree. It is believed that asteroids, particularly those that are "contact binaries" have a surface layer of crushed rock. It may just require shoveling. If the we are talking dead comets, then heat application to the the subsurface ice may be all that is required.
That isn't to make light of the mining technology needed, but I am certainly not clear of the value of humans (with all the mass associated with their life support and transport). Robots would certainly need to be more autonomous than they are today, as control from Earth would be a slow process.
With regard to SteveO's issue about fractionation. Obviously many mineral concentration processes on Earth have not occurred even on the proto world that became the asteroids. Gravity fractionation has, which is why asteroids display different composition spectra, although they fall into 3 main classes. Mining the Sky by John Lewis gives only a very brief description of this, certainly too basic for anyone with geology education. But the fact is that much of what we think we know is based on little data, almost all telescopic and a lot of inference. We need to get some "pads on the surface" to get good data. I believe that a robot visiting an NEA is a better way to achieve this than capturing a very small NEA for human sampling later.
I am beginning to believe that our host is either largely disingenuous about his stated goals (IE. a manned space program, STEM education, technological advancement, democratization or climate change, etc) or romantically ignorant as to what constitutes the human motivational paradigm.
According to the Behaviorists, including sociologists, psychologists & most economists, human behaviour is not necessarily rational, it does not correspond to moral 'Things We Ought to be Doing Anyway (TWODA)' and, instead, it is the complex product of a number of variables beyond the proverbial 'carrot and stick'.
First & foremost, David discounts the motivating effect of fear which (perhaps) was the single most important motivating factor in mankind's initial push into space, specifically the threat of Nuclear Armageddon as fostered by the Cold War.
Second, he pays only token lip service to Discounted Utility, a factor that automatically 'discounts' the future size of a potential reward by at least 30 to 50 percent, perhaps more depending on cultural background, which therefore requires an ever increasing reward (monetary or otherwise) in order to remain effective.
Third, he overlooks a huge number of motivational variables, including (but not limited to) perceived effort, degree of difficulty, prerequisites, discomfort, gratification, relative life expectancy, relevance and self-efficacy.
Most importantly, he routinely shoots himself in the foot and undermines his own position with inherent positional contradictions:
(1) By remaining 'optimistic' about the earthly environment and negative about the potential threats from SETI and lunar littering (!!) -- contradicting Stephen Hawking on all counts, btw -- he makes space exploration seem that much less attractive;
(2) By optimistically over-estimating current human technological & educational accomplishment in almost every discipline, accompanied by a potentially infinite supply of 'well dones' and 'attaboys', he actually discourages further advancement in those disciplines; and
(3) By advocating any number of 'helpful kindnesses', charities and other measures of social mollification, he deliberately decreases the level of human discontent and discomfort below the breaking point necessary for human action, virtually guaranteeing oligarchic politics as usual.
Now, if he really wanted to encourage human space exploration, STEM education, democratization or end climate change, then he would work the 'fear button' much harder with doom & gloom pessimism, promise infinite rewards with little effort and systematically attack all the other motivational variables to achieve his stated goal. He has no choice, really, unless he doesn't believe in his stated goals after all.
Locum, Dr. Brin's problem is that (from my perspective) he's irrational when it comes to the Moon. He considers it a trap when in fact it's a stepping stool. He wants us to do the Next Big Thing, to go to the asteroids and Mars, rather than accept the fact that humanity, in all of its irrationality and idiocy, has a fundamental love of that gleaming grey-white orb in the sky above our heads.
He sees the Moon as a waste of time because we were there already. He ignores the fact that there is plenty of science to learn that putting boots on the soil will allow. He also ignores the fact that by perfecting lunar habitations, we can in turn better prepare ourselves for safely visiting other planets without contaminating them or bringing back accidental organisms under non-controlled circumstances.
Most of all, I get the feeling he tries hard to avoid mysticism and the like. Thus he sees the Moon as something to avoid because we are so attached to it. It's better to go to the asteroids (which are his focal interest and thus he's prejudiced toward them) in his eyes than to the Moon because he believes we can achieve more by flying before we walk.
I speak from the mindset of one who has grown up with science fiction with lunar bases and the use of the Moon as a stepping stool. I am likewise prejudiced, but part of this prejudice is a desire to go to the stars... walking in the footsteps of so many fictional explorers before us. I see the Moon not as a trap but as a step outward. And by establishing ourselves there, we can not only be protected from tragedy should the Earth's ecosystem collapse or a civilization-killing asteroid pound the Earth into mint jelly, but even have the seeds available from which to Uplift ourselves (in essence what was described in Robert L. Forward's "Starquake" only without the "helpful aliens" (humanity in that case)).
Why go to the Moon? Because we can at this point establish a permanent colony on the Moon within the next 10 years and in doing so start establishing the seeds to protect our species from extinction. And because in doing so, we start the process of colonizing the solar system - much as Europeans (well, Vikings at least) started with Iceland, then moved on to Greenland, and finally tried to colonize Vinland and would have succeeded had not a hostile native force been located there!
I'm sure Dr. Brin will refute this. But my reasoning is fairly sound on this regard. (And I must admit, it would be interesting to see Dr. Brin do a full-out blog post on why HE feels returning to the Moon and establishing a permanent base there is in fact a bad idea that's doomed to failure.)
Metal asteroids are *extremely* rare, leftovers from a differentiated body. They only fit the mold of "meteorite" to us on Earth because they survive re-entry. My understanding of asteroidal composition is that the vast majority are stony, hence the need for ores.
And yes the Inuits made tools from meteorite iron, but while it is amazing compared to, say, walrus tusk, it is very very poor compared to steel. In order to get all the junk out and make something strong enough to use you have a lot of pyrometallurgy to do. Plus, you are going to need a whole new process to replace blast furnaces which use massive amounts of limestone (none in space) and coke (pure carbon, very rare and expensive in space).
Ack - more to come, but I have to go to a meeting... :)
Could use a citation on the "extremely rare" metal asteroids.
locum is funny. He leaps upon "contradictions" which really amount to my being able to see all sides, pros and cons.
"Oh no! Brin sees some reasons for optimism and some for pessimism! He sees some opportunities and … dangers! What a hypocrite! Doesn't Brin know you just have to be one thing? Aimed in a single, monomania direction? Preferably cynical rage?"
The sick, sick, deeply-sick notion that "we must ensure that everything will get worse, really fast, so that the level of human discontent and discomfort (will plummet) below the breaking point necessary for human action…" is one of the foulest nostrums of all time. It has been spread relentlessly by bastards.
This sort of deliberate sabotage of civilization has NEVER resulted in an improved human condition. What it has achieved - at times - is radicalization followed by violent failed revolutions and new, oppressive oligarchies. The French, Russian and Chinese revolutions, for example. It has never ever resulted in moderate, invigorating, freedom-friendly revolution. Ever.
Those better revolutions have always resulted from rising comfort and rising hope.
Oh, sorry, since world trends are already positive, my urging folks to help move forward even faster amounts to working WITH momentum. Locum wants us to reverse the rapid rise of world middle classes so that the following revolution will create an empowered world middle class. Ah, logic.
RobH… there is zero economic incentive to maintain a lunar bas. It give us nothing except a tourist destination. And there is a company working on that! Let the rising zillionaire oligarchy pay for return trips and then base-hotels! They have all the money, anyway and this might siphon some off to something positive.
SteveO a lot of the chondrites have nickel-iron inclusions.
I thought that particular screed could be disregarded the moment it gave credence to behaviorists, who assume that the instinct-driven mind of the rat is a perfect model from which to extrapolate the behavior of a sapient species such as humanity.
I should have guessed Dr. Brin would short-thrift my argument on lunar colonization. However, I must admit seeing his claim that we need an economic reason to go into the solar system. While this is true for private industry, NASA is a government organization and thus if it (or NASA and other supranational space organizations working together) chose to establish a permanent lunar base... we'd not need economic reasons. Scientific could suffice.
For instance, building a large radio telescope on the far side of the Moon at the South Lunar Polar region - one that is fully blocked from the Earth and thus is shielded by our electromagnetic chatter. This could be connected to a lunar base via a landline. And having "feet on the ground" would mean when the inevitable problems arose concerning the remote vehicles building the telescope happened allows for a more rapid response to the problems.
A second lunar base would likely be established in time somewhere near the equator for the simple purpose of building a lunar space elevator for easy access to and egress from the Moon. (Even better, we could connect the two bases with a tube transport using electromagnets to elevate the vehicles - the vacuum would allow much faster speeds and thus short transit times.)
So really. Outside of economics, why are you so against a lunar base? The gravity isn't so great as to "trap" people there - we went there in a tin can, landed safely a half dozen times, and left using far less propellant than was needed to leave the Earth's orbit. And all that without building our own fuel on the surface.
The lower gravity is useful scientifically to determine the effect on humanity without a huge expensive station with rotating sections. If lower levels of gravity proves capable of keeping bone resorption from occurring and muscle atrophy, then when we DO go to other areas, we don't need areas with nearly as much centrifugal force to simulate that gravity.
There are scientific reasons for doing so. Your claims against it do not seem more than an ongoing scientific dispute against returning to the Moon - it would be akin to Europe saying "there's no need to go to the New World, Columbus already went there!"
Your arguments against the Moon have become most lackluster, Dr. Brin.
"negative about the potential threats from SETI and lunar littering (!!) -- contradicting Stephen Hawking on all counts, btw"
I haven't heard Hawking speak on "littering", but I have heard him warn about SETI.
[I disagree with Hawking's reasoning, where contact alone is a risk. The native American culture wasn't destroyed by mere knowledge of/from advanced races. It was destroyed, literally and culturally, by invasion (and largely disease.) Hence why I disagree so strongly with active SETI (and thus echo-echo-echo-chamber David), since either They aren't there to hear us, or They are being quiet because that's the smart thing to do. Either option makes shouting into the dark the dumb thing to do.]
"By optimistically over-estimating current human technological & educational accomplishment in almost every discipline, accompanied by a potentially infinite supply of 'well dones' and 'attaboys', he actually discourages further advancement in those disciplines"
Nothing in psychology or experience that says that. Only where there is no correlation between reward (praise) and actual success will the reward fail to encourage further effort. And only where the reward is seen as counter to success (those who fail are given greater reward) will the reward undermine effort.
"By advocating any number of 'helpful kindnesses', charities and other measures of social mollification, he deliberately decreases the level of human discontent and discomfort below the breaking point necessary for human action, virtually guaranteeing oligarchic politics as usual."
No, there's a Maslow's Hierarchy at work. If people are fed, they are not sated, their hunger merely turns "upwards".
"then he would work the 'fear button' much harder with doom & gloom pessimism,"
Fear yes, but pessimism is not motivating. The Apollo program was not motivated by pessimism. On the contrary, there was a football-team arrogance behind it, "Are we gonna let those Ruskies make fools of us?" "NO COACH!" Hell, he even used a football team example, Rice vs Texas. Kennedy responded to the embarrassment of Gagarin with a challenge to go to the moon. Not just "I guess we'd better keep up", but "let's jump ten steps ahead." Fear plus pessimism makes you build bunkers. Fear plus optimism makes you build space-ships.
"Most of all, I get the feeling he tries hard to avoid mysticism and the like. Thus he sees the Moon as something to avoid because we are so attached to it."
Heh, this is why I oppose manned Mars programs. I feel the "second Earth", "humankind's natural second home", etc, is too blinding. Mars will consume everything we throw at it for as long as we want to throw it. It will not be remotely self-sufficient for centuries, and will not return any advantage to other space endeavours. It's a hole, not a stepping stone.
The moon, as a NASA program, tends to also be a hole. While in theory there may be resources (and experience) that enhances other space activities (like the famous polar ice) but in reality every NASA plan quickly devolves into an Apollo-like waste of resources. That's why I supported the asteroid mission over moon and Mars, since I hoped it would break them out of their insular "silo" mindset.
But bizarrely, even the asteroid plan quickly devolved into little more than an Apollo-variant. Which, along with SLS, suggests that NASA isn't even ready for the most basic foward-looking human space program. This has convinced me than NASA is incapable of any outward expansion. We need to go back to the basics, and start building stepping stones we've missed. Cheaper launches. Private/commercial manned launches. Private/commercial manned stations. Cheap, off-the-shelf modular space probes. Space-only transfer vehicles (tugs), and refuelability.
I think the shift in climate reduced their range into Vinland as much as the hostile natives. After all, they coped with hostile natives in Europe. The shift in climate ruined the Greenland colony, and reduced the power of the viking tribes at home, cutting off the flow of new men and ships. It ended the "viking" era. Although successful viking colonies in more moderate parts of Europe (Normandy, north Germany, western Russia) had plenty of success.
"yes the Inuits made tools from meteorite iron"
Everyone made tools from meteorite iron. The Inuit just had a particularly large and obvious source.
Re: Iron plus crap still needs refining.
Probably. But starting with 100% metal is a hell of a lot easier than starting with a 20% oxide ore. And there will invariably be things that can use "wrought asteroid", bulk items, the bucket on a moon-dozer, the chassis-frame on the tractor. According to the guys on the Lunar-ISRU team, asteroidal (and hence lunar) iron-alloy is weaker than steel, but stronger than wrought iron. And humans did an awful lot with wrought iron.
Oy, okay Robert: "The lower gravity is useful scientifically to determine the effect on humanity without a huge expensive station with rotating sections."
Bah. We would learn useful things from building those rotating stations. But even if we use underground lava tubes to make lunar habitats (we are funding this at NIAC!) what would we DO there?
Likewise, my graduate advisor was the guy who forecast lunar polar ice. I am glad of it! Someday, sure. But (1) it is not super plentiful and (2) landing and takeoff from the poles is rather harder than at the equator and (3) What do we DO there?
Look, over the long run we will do all these things and I hope use Helium 3 as well! I'd love to see moon bases! But I want the near term aimed at stuff that actually helps sustain us out there and sustain real interest. If zillionaires want to go then fine, let them finance the moon return.
The NEw World had great reasons to go back to it. I've not seen any near term reasons for the moon.
To avoid contaminating the new thread...
"building a large radio telescope on the far side of the Moon at the South Lunar Polar region - one that is fully blocked from the Earth and thus is shielded by our electromagnetic chatter. "
Actually, you only need a few millimetres of aluminium shielding to completely mask the Earth's chatter. The remaining 3000km is wasted.
But these (telescopes and other science) are examples of the things that are stripped out of a NASA lunar program almost immediately on its creation. Even Apollo only flew an actually proper geologist on the last mission. (Only the first should have been an all pilot crew.) Likewise, Constellation went from "permanent lunar base, polar telescope, refueling a Mars mission" to Apollo-redux equatorial sample return.
"This could be connected to a lunar base via a landline."
Only if it's close. Radio is more efficient. You pick your frequency band to minimise interference with the telescope. L2 and L5 relay satellites to bounce the signal back to Earth (avoiding hundreds of km of cable and related maintenance.) (You could even use lasers. NASA has tested lasers of the lunar reflectors and gotten hundreds of megabytes of throughput. That prevents interference with a radio telescope, and allow single-band filtering for even optical telescopes.)
"determine the effect on humanity without a huge expensive station with rotating sections."
We haven't even done animal research on variable gravity. That requires only a rotating drum inside a single module. And can simulate widely different gravities. 50 years and we haven't even tried. It's bizarre.
Moving to human research would require a single mini-station (ie, a single all-in-one module), attached to a tether with a counterweight. The counterweight could be part of the infrastructure, but I suspect for the first generation, it's technologically wasteful. Just use the spend upper-stage that lofted the main module.
"lunar space elevator"
We aren't build space elevators in the next two decades. So no.
But even long term, no. Lunar space elevators are around a couple of hundred thousand km long, for little benefit. Put simply, you need a major industry in space in order to build it, and since you then already have a major industry in space, you appear to have already solved the problem anyway.
If instead you use shorter rotating tethers in lunar and exo-lunar orbits, you can still virtually zero your energy use, while drastically reducing your material requirements. It's also incremental. Any short tether would provide some benefit. We can start now. And as you develop the technology you can increase their number, lengths and payload capacity.
(By matching the orbit, rotation speed, and tether length, you can have the tether rotate so that the tip "touches" the lunar surface at a set of specific locations. At which you build pick-up towers to suspend or catch payloads. Technologically and materially, it's likely to be easier than a rail-launcher on the surface. Plus it just seems kinda cool to have this thing reaching out of the sky to grab stuff.)
Elevators are also slow. To avoid damage to the cable/ribbon, you are limited to hundreds of km per hour on the first few generations. That means your trip from the ground to the release point could take days, even weeks. With a tether, you are rotated from pick up to release in half-the-tether's-rotation-period. A few tens of minutes, probably. And you can relay from one tether to the next. Surface to L1 or L2 via the low lunar orbit tether. L1 to Earth orbit via the L1 tether, or L2 to the rest of the solar system via the L2 tether. Earth orbit to low reentry speed via the Earth orbiting tether. (Which is another
The "trap" of the moon isn't gravity (unlike Mars), it's that NASA will narrow down its focus to the smallest possible program that meets the "big" goal ("Landing a man on the moon", "Building a base") while preserving the elements that Congress actually supports ("Big rocket".) And even that consumes all available funding, since the second criteria (keeping Congress happy) tends to be inevitably the worst, most wasteful path. That funding is then taken from other programs of value.
@Paul451 - Another advantage of tethers/skyhooks on the moon is that they avoid most of the very abrasive dust. When Clarke wrote "A Fall of Moondust" the dust was described as being like talcum powder. The Apollo footprints also make the dust look benign. But we now know that it is very abrasive and gets into everything. Dealing with it is a problem. This makes maintaining a rail gun or accelerator problematic (robotic maids dusting it every 2 weeks?). The tether solution avoids this because it doesn't have [m]any moving parts.
For a different perspective, I'd like to link to one of Charlie Stross's blog entries:
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