Wednesday, December 14, 2011


Take Microsoft VP Paul Allen, add Burt Rutan and Elon Musk, and stir:

Compare to the Skylon; this is a great idea, as it provides a completely reusable first stage and eliminates the need for a launch tower.

(via Cosmic Conservative)

Wednesday, November 23, 2011

Last Dragonflight

“Gone away, gone ahead
Echos roll unanswered
Empty. Open. Dusty. Dead.
Why have all the weyrfolk fled?

Where have dragons gone together?
Leaving Weyrs to wind and weather.
Setting herdbeasts free of tether.
Gone, our safeguards. Gone. But wither?

Have they gone to some new Weyr?
Where cruel Threads some others fear?
Are they worlds away from here?
Why, oh why the empty Weyr?”

Tuesday, September 06, 2011

A way out of economic meltdown

In the article Labor Day Blues, Robert Samuelson points out:
To reduce unemployment, the economy must create enough new jobs to absorb entrants into the labor market and the existing out-of-work. Shierholz has calculated how many jobs would be needed to lower unemployment (9.1 percent in August) to 5 percent over five years. Her estimate: 16.9 million. That's an average of 282,000 jobs a month. The trouble is that this rate of job creation far exceeds the present level (105,000 a month since early 2010) or even the level (240,000) achieved during the boom between 1993 and 2000.

You can tinker with Shierholz's assumptions, but the main conclusion doesn't change. Even with rapid job growth, unemployment will descend slowly. With sluggish growth -- or another recession -- it may remain high indefinitely. There are no quick fixes. Unemployment will increasingly define our economic prospects and politics.

...Still, high joblessness' harshest effects fall on the jobless. "We're creating a bifurcated society," worries Harvard economist Lawrence Katz. "We're talking about a lost generation of younger workers and displaced workers." Younger workers have a harder time starting careers. Because many skills are developed on the job, long unemployment spells can lower lifetime earnings.
(via Instapundit)

It is the youngest workers who are going to need new jobs the most. It is those entry level jobs that provide the most real-world education to a young person. Clearly, focusing attention on getting young people working has merit. So what can governments do?

The first thing they can do is look at what has already been done and examine the results. For decades, program after program has been introduced, policy after policy enacted, all intending to get young people working. Which of these have actually produced positive results? Which have failed?

The second thing to do is realize that the list of successes is very small. Indeed, it seems every time governments enact a new program or department or law intending to increase youth employment, the problem gets worse.

Let's take minimum wage laws, as an example. Suppose in some jurisdiction the minimum wage is $7 an hour. An employer, perhaps a new restaurant, has $56 per hour budgeted for entry-level employee positions. Therefore, they can hire 8 young people for their first jobs. But wait! The government of that jurisdiction raises the minimum wage to $8 an hour. The restaurant's sales haven't changed. Now there are only 7 entry level jobs available. Minimum wages laws are just one example of the job-destroying effects of trying to solve a problem by adding new rules, regulations, laws, programs and so forth for employers to deal with.

Here's another example. It is nearly impossible for a young adult starting from scratch to open their own business in much of the Western world; it is doubly difficult to do legally if that young adult wishes to employ anyone else. The amount of paperwork that is required for legal compliance with the myriad regulations and laws and bylaws across various levels of government and government agencies is beyond daunting. In Europe, if they printed it all out, the paperwork would run to something like 10 railway boxcar loads. 99.9% of all the red tape is completely irrelevant.

On the other hand, if the process of starting a small business was simple enough for an 18 year old to do in an afternoon, and if the paperwork required for operation massively reduced, then the unemployed (not just the young unemployed) would be starting businesses of their own and creating jobs.

That's not to say that all regulation and law must end. What it means is that the vast majority of such are completely unnecessary. Eliminate these unnecessary impediments, get the hell out of the way, and watch the economy recover.

Tuesday, August 30, 2011

A modest proposal for NASA

The Senate wants NASA to build a specific rocket using specific contractors in specific districts. The rocket scientists in the Senate have also specified a specific payload mass: 130 tonnes. This is to be done even though NASA hasn't had a budget to work with in years, only a series of Continuing Resolutions, and all foreseeable indications are that NASA's budget is going to go down, not up. Also, there is no payload on the drawing boards that weighs 130 tons and must be launched all at once as a single unit. The two different mass specifications above are also courtesy of the Senate rocket design specialists.

If one wished to be uncharitable, one would suppose that a few Senators with powerful positions on committees overseeing NASA and with NASA contractors in their states were constraining the design space for NASA not for the good of the nation but to get themselves re-elected.

However, let's be charitable. Let's suppose the Senate rocket designers in fact have a 130 ton/ne payload in mind, a super-secret payload that has super-secret funding, because it sure isn't funded through NASA's budget continuing resolutions.

Let's suppose the SLS (Space Launch System or Senate Launch System, take your pick) gets built and the Senate gets to launch Super Secret Payload number 001. What? You mean that there has to be more than one payload to justify development of an entirely new rocket system?

Suppose that they get the rocket built and integrate the payload, and SLS could lift 130 tons to orbit but SSP001 is 130 tonnes. Oops! Meh, that sort of thing happens at NASA from time to time. Or suppose SSP001 is 129 tons, but once they get it up there they realize they need something twice as big. They can't do orbital rendezvous, which has hardly even been tried at all except in assembling Mir and ISS. So they'd need a rocket that could lift a 260 ton payload all at once. And eventually they'd need a rocket that could lift twice as much as that.

Well, why go for half measures? Why not just build the rocket we'll eventually need, right away?

What I propose is that NASA build a rocket capable of lifting 16 million tonnes to escape velocity. Surely that would be the biggest single payload that NASA would ever need. If we do that, then NASA will finally be able to get started with Beyond Earth Orbit manned exploration.

To be conservative, let's use 12 km/s as our delta vee and 300 s for our specific impulse. If we further assume that the mass of the ullage is negligible, the rocket equation gives us a total fully-fueled mass for our Somewhat Large Space Transport of around a billion tonnes.

Now that's a rocket!

Of course, a full flight test of such a rocket would be very expensive. And the logistics of mounting such a huge payload on top of the SLST would be difficult, thus employing lots of people in key congressional districts. There's also the minor inconvenience of there being no possible launch pad capable of supporting that mass without burning down, falling over, and then sinking into the swamp.

However, Gaia has smiled upon us, and what was once thought an environmental disaster of Biblical Plague proportions could literally be the launchpad to the future. Apparently (and I haven't been following this too closely, just what I see on CNN) the Gulf of Mexico is some sort of oil-slick covered watery desert of death due to some British guys or something. Well, liquid Oxygen and liquid Hydrogen are lighter than water, so you could just float the whole rocket out into the Gulf and you don't even need a launch tower. I totally stole that idea from Sea Dragon. Any launches of the SLST wouldn't harm any wildlife in the Gulf because that's all dead from corporate greed or something which was probably Bush's fault anyhow. My details on this are kind of hazy because I haven't been watching CNN much lately.

All the unemployed people in the Gulf States could then be put to work either by physically manhandling the 16 million tonne payload onto the SLST or by joining hands and singing Kumbaya. Either way, it's financial stimulus. It'll be a huge financial stimulus when that sucker gets launched, too.

note: The US Capitol building and its grounds cover about 16 city blocks, so about a 400 meter by 400 meter area. At 100 tonnes per square meter, that's 16 million tonnes.

Saturday, August 20, 2011

Online Introduction to Artificial Intelligence Class

Stanford University is giving a free online class in Introduction to Artificial Intelligence. The course is presented by Sebastian Thrun and Peter Norvig, and is based around the textbook Artificial Intelligence: A Modern Approach. I signed up for the course two days ago, and 13000 more signed up since then; there are now 113 thousand people signed up for this unique opportunity. Sure won't hurt their book sales, either.

Friday, July 29, 2011

default damfoolishness

I keep seeing stuff like this article - from an Econ 101 professor no less - and it frustrates the hell out of me that people who should know better, don't. One would think that CNN could have found an Economics professor in the United States that actually knew the meaning of a basic financial term like "default".

Let's be clear about the definition of default: if the US defaults then it means that the country didn't pay the interest on the debt. Not the principal. Not SS or Medicaid or Medicare or the military. Default has nothing to do with those expenditures. Just the interest.

To further clarify: the President of the United States is legally bound by the constitution to pay the interest on the debt. The money is there, taxes more than cover that amount.

So, if the US defaults, it will be because the President chose not to pay the interest, but diverted that money away from where he is Constitutionally obligated to spend it, directing it instead to something else.

The US doesn't default if it unilaterally lowers the Social Security payments to seniors. The US isn't considered to have defaulted if it gives its military a pay cut, or cuts back on any other government expenditure. It only defaults if the US doesn't pay the interest on the debt. Econ 101 professor Steven Kyle should know this, must know this. If he doesn't then he's not competent to teach Econ 101 in the USA. However, he writes:
How to get out of this fix? Certainly the easiest solution in the short run would be for Congress to pass the one sentence of legislation required to raise the debt ceiling
The debt ceiling has nothing whatsoever to do with whether the US defaults or not. The only trigger for a default is nonpayment of interest on the debt. When Obama talks about default, that's what he's talking about - vetoing a payment of the interest on the debt.

If the US defaults, Obama owns it. It's his weapon and it is turning into an albatross around his neck.

The US debt ceiling is to the interest as your personal credit card limit is to your minimum monthly payment. Saying that the US must raise its debt ceiling to avoid default is the same as you telling your credit card company that you need a raise in your credit card limit so that you can make your minimum monthly payment. They'd laugh in your face, just as those that propose raising the debt ceiling to avoid default should be met with derision and scorn. Sadly, the same people are actually teaching Economics 101. It is to weep.

Thursday, June 30, 2011

SixthSense Computing

The interface between the physical world and the digital world becomes richer and more complex as the machines themselves improve. What once was only encoded by punchcards gave way to keyboards, then joysticks and light pens and mouses (mice? not sure if the biological plural applies) and haptic interfaces. But what if your entire physical environment could be the interface to the digital world? Enter SixthSense computing.

SixthSense is an Open Source project. The current device costs about $350 to build, and instructions on making your own will soon be made available on the SixthSense site.

Thursday, June 02, 2011

space for all of us

Recently Pajamas Media held the Great PJ Media Space Debate between Rand Simberg and Bob Zubrin.

At the core of their debate is a single issue: heavy lift versus propellant depots. There are advantages and disadvantages of both approaches. However, their debate is about tactics and objectives and loses the forest in the trees.

What's missing in the debate is Vision. Now, to be sure, Bob Zubrin has a vision, an extremely detailed vision of landing a man on Mars, fast. Rand Simberg has a vision, too, of the commercial market driving down launch prices for all missions. Others have different visions - Paul Spudis wants to extract Hydrogen and Oxygen from lunar ice trapped in perma-dark craters from a base on the Moon's South pole, for instance.

All this debate over space policy is about the How and Where, but very little is about the Why.

Now, I'd wager that most of the people who care enough about space to (in some cases) make a living by writing about space, would want to go up there themselves. Each would have their own particular reasons for wanting to go. They all (not just the three above) have different destinations in mind, and different ideas about what to do once there. Each naturally tries to steer the debate towards whatever they think will accomplish their personal goals.

These visions are all worthy ideas, technically possible with today's technology, and all suffering from a lack of long-range Vision. Each group is only looking at the next decade or so. This is understandable, as after all we are debating current space policy, arguing about what to do next and how best to go about it.

Suppose one group wins out and is successful over the next ten or fifteen years. What's missing is the answer to the question "then what?" What happens after Zubrin gets a man to Mars? What happens after Simberg gets cheap access to orbit? What happens after Spudis gets his lunar base and starts producing LOX? What are we doing all these things for?

Fifty years after Kennedy proposed the moon landings, there is still no clear understanding of what we should be doing in space and why we should be doing it. Or rather, there is a reason and we've all been just kind of avoiding saying it, because the idea is so literally far out.

the goal

The goal is the settlement of space.

That implies large numbers of people living and working and raising children off the Earth. It implies not only cheap launch to orbit, but a lot of other challenges to be solved, technological and otherwise.

I started writing this blog post on May 22nd, and nine days later this keynote speech by Jeff Greason at the ISDC appeared at MoonAndBack, laying out much of what I'm talking about here in detail, in particular the difference between the tactics and objectives being discussed in the PJMedia space debate and the Goal and Strategy. Here's the slide where he lays it all out, without getting into the minutae of the tactics:

It's a pretty good starting point for discussion purposes, and as Greason says it is a strategy, not necessarily the path to be taken but in a better general direction than the status quo. And for once the Goal of all this effort - the human settlement of space - is clearly stated.

something's gotta give

For decades the US government has been living beyond its means, and the time is rapidly approaching when government will have no choice but to cut expenditures and restructure. As Jeff Greason mentioned in his ISDC speech, if in ten years NASA has no more progress than the last ten years, NASA itself could be greatly diminished. The bottom line is that NASA's budget will not increase in the coming years and may even decrease slightly, as a most-likely scenario.

NASA is going to have to change the way it does business. Greason mentioned that it is going to have to assist in developing technologies which will result in products that have other customers besides NASA in the future - and then get out of the way and move on to the next thing while private companies fill in behind them.

However, a more fundamental restructuring of NASA may be necessary to implement a Greason-esque strategy. Einstein asserted that doing the same thing over and over, expecting different results, was insanity. The same NASA centers being run the same way using the same risk-averse methods that have ossified the agency over the last several decades will not give different results. The Augustine commission recommended changing all NASA centers into Federally-Funded Research and Development Centers, like JPL is currently, and that is a good start.

However, the change at NASA might have to go even deeper than that. One way of reducing NASA's budget, without laying off a bunch of voters, is to reduce NASA to core competencies and transfer those non-core parts to another agency.

In the Winter 2011 edition of the New Atlantis, James C. Bennett proposed a United States Space Guard modeled after the Coast Guard. In his essay Bennett points out that there are many space-related functions in government outside of NASA, in agencies in which these functions are not core competencies: the Department of Transportation regulates suborbital flight; the Air Force tracks orbital debris; NASA has infrastructure operations that are not related to R&D, exploration, or space science; the Department of Commerce operates weather satellites.

All of these functions would be transferred from the respective agencies to the new Space Guard, allowing each agency to concentrate its resources on its core missions. This new entity would likely be in the Department of Commerce or the Department of Transportation, and not in the Department of Defense. For instance, since tracking orbital debris is a function not directly related to war-fighting, it is not a core function of the Air Force and thus should be transferred to the Space Guard.

Bennett also proposes new functions and responsibilities for the Space Guard: space-transportation contracting; in-house space transportation engineering expertise; space situational awareness; space debris reduction and mitigation; a "Space Reserve" capacity; enforcing order ("USSG officers would be, like Coast Guardsmen, officers of the U.S. government capable of operating as a constabulary"); and finally search, rescue, and recovery operations in space.

This idea has merit. It allows several departments to reduce their budgets (most importantly for PR purposes in the Department of Defense) without losing capability. It establishes a central civilian agency associated with the routine use of space, well inside the envelope that it is NASA's job to push. It allows NASA to ignore the routine aspects of its current operations, and instead to focus on cutting-edge research and development, exploration, and space science exclusively.

Now, the creation of yet another new government department is not going to be an easy sell in a time of budget cutting. It won't simply be a matter of money taken from the various agencies and all transferred to the new Space Guard, all done on paper with zero net spending reduction. Further budget reductions can reasonably be expected in most government departments, including Defense and NASA.

NASA will need the commercial sector to step in and provide routine launch services, and the commercial sector will need NASA as an anchor tenant and technology driver. As Greason said in the ISDC speech, the cost to the taxpayer per person in space has to come down, continuously and over a long term basis, for space settlement to ever be a reality. The only way that will happen is if the government is paying for routine services and technology development assistance and then getting out of the way of the private commercial sector.

The restructuring of NASA (and other non-military government space operations) and the implementation of the Greason strategy or one like it are a great start. However, there is still one crucial element needed to make the settlement of space a reality.

there's gold in them thar hills

Mark Twain said "Buy land, they're not making it anymore". The idea of private individuals or corporations owning land off the Earth - on the moon or other celestial bodies - is crucial to settlement. When a corporation is setting up a mining operation to produce propellant on the moon from lunar ice, it is critical to the business plan that the company has the legal right to own the propellant it produces. If a company is mining asteroid (6178) 1986 DA, it wants to know that it owns whatever Gold and Platinum and whatever else it mines there. If a young couple strikes out into the black to settle on Mars, they want to know their kids will inherit the habitat they build.

This requires legal recognition of property rights in space. The 1967 UN Outer Space Treaty prevents the United States and other nations from "national appropriation by claim of sovereignty, by means of use or occupation, or by any other means" of celestial bodies. However, this does not prevent the recognition of ownership by private citizens or corporations of extraterrestrial real estate.

It is this formal recognition of property rights that is the final missing element necessary for the settlement of space. This might be a function of the Space Guard, or another entity entirely. This recognition wouldn't imply American sovereignty over the property involved, just a recognition of the fact that a claim of ownership is valid. The recognition could and should be extended to non-Americans who go out and settle space, as well.

A mechanism in place for the recognition of property rights would allow corporate investors a way to get a return on their investment, and would provide collateral for financing for groups of settlers to set up their settlements. This in turn would lead to infrastructure improvements on Earth, in orbit, and at the various destinations, and enable further waves of settlement. Without property rights, investment will remain a trickle. With the recognition of property rights, the investment - and space settlement - will turn into a flood.

Wednesday, May 25, 2011

Sunday, May 15, 2011

moonbots 2.0

Take three of my favorite things: robotics, LEGO, and space. Mix them together and stamp them with the logos of the X-Prize foundation and Google. The result is a unique educational experience: a Google Lunar X-Prize LEGO Mindstorms challenge called Moonbots 2.0:

Registration closes June 13th.

Sunday, May 08, 2011

space programs about space

Trent Waddington has a problem with this segment of a Neil deGrasse Tyson speech:

To which Trent says:
It disappoints when a speaker says something like this.. it fills you with inspiration for about five seconds, only to have the nagging rational part of your brain chime in with: umm, excuse me? That's not actually true, ya know. I think kids who are inspired by such speakers to follow their dreams will feel terrible betrayal when they eventually discover they've been lied to.
In the comments section Dr. GeGrasse Tyson defended what he said, but I think Trent's point still stands: spinoffs are not a justification for a space program.

By its nature a spinoff technology must be developed for some purpose, which is later developed as a consumer product - which may be used for a vastly different purpose than for which the technology was originally developed, as with the LASIK example. And if that original purpose isn't justified, then the spinoff technology never happens at all and we would never even know what we were missing. In other words, spinoff technologies occur after the fact of justification and are thus not the justification in themselves.

We didn't establish space programs in nations all over the world so that we can have LASIK. Spinoffs like that are nice to have, but they aren't the reason that there is a NASA and JAXA and ESA and all the rest of the acronyms.

The reasons for the existence of all these space programs extend back to the geopolitics of the Cold War, and each space program has had to come up with continuous justifications for its existence. They're all trying to answer the question "why bother with space?" Or more specifically "why should a national government bother with space?"

National space programs have to walk a tightrope. On the one hand, there are the multiple potential benefits of using space - the limitless energy supply, the limitless raw materials, access to zero gee and hard vacuum and unobstructed sight lines. So, those potentialities have to be acknowledged, and it must at least appear that progress is being made in our understanding and ability to use space to our benefit.

And then there is the other side of the coin. Imagine for a moment a bank with a physical vault located somewhere deep under the surface of the moon, and a transportation structure that enables cheap trips to space. What country would have jurisdiction over that bank? Would that bank be an extra-national entity, outside the law or reach of any nation?

There are enough problems policing the inner cities now, what do you do when millions of people are living in the asteroid belt? What happens to a nation's decades-long investment if second-generation Belters start grumbling about independence?

This is a fundamental problem with national space programs. If they are wildly successful, then large numbers of their taxpaying citizens would be able to physically go beyond the reach of the tax man, spreading out over roughly kajillions of cubic miles of space.

So a national space program must appear to be making progress while simultaneously making that progress as glacial and expensive as possible. The "expensive" part is key feature, as it discourages private individuals and small businesses. The weak tea that we get in return - pretty pictures from Hubble, the occasional robot scattered here and there, the tepid pace of ISS construction - are supposed to indicate progress. It worked for NASA for decades.

Not anymore. Entrepreneurs like Burt Rutan and Elon Musk and Robert Bigelow and many, many others have started to peel back the facade. They have demonstrated that the hugely-expensive development programs NASA has historically undertaken simply don't need to be expensive. Consider: in 9 years SpaceX has gone from a clean sheet of paper to having developed two new rocket engines, two classes of rocket, and a crew capsule, all for a grand total of 800 million dollars. That might sound like a lot, but NASA's yearly budget is around $18 Billion with a B. NASA spends SpaceX's entire 9 year investment every 16 days.

The reason for the difference is that SpaceX is actually about space. Elon Musk wants to put his own boots on the soil of Mars. He realized that in order for that to happen, he had to make a business that would make it possible for large numbers of people to go into space. So, every decision about SpaceX is made with the larger goal in mind: make it possible for large numbers of people to travel to orbit. And that only happens if SpaceX makes a profit.

Robert Bigelow developed the expandable modules with a goal in mind: space hotels. He knows hotels and also knows they grow up along with any transportation infrastructure. Bigelow Aerospace has a purpose, and it is about making money in space.

Richard Branson has an actual purpose in space: making money from suborbital tourist hops, and eventually going for orbital tourism. It's the same with example after example of the new breed of space entrepreneurs: the purpose of space is to make money.

That is the way it has to be. It is the only way the large numbers of people will go into space, which is fundamentally at odds with National interests. It is also the only way that a space program will actually be about space, because the search for profit won't allow for any distraction from the goal. NASA and all the rest can keep doing what they are doing, spending huge amounts of taxpayer money for miniscule advances, which the profit-seekers leap past them. You watch.

Saturday, May 07, 2011

Monbiot comes clean

It took him a decade, but Guardian author George Monbiot has finally realized that environmentalism doesn't work - at least, not as it has been practiced and promoted for decades.

This is a guy at the core of the whole Green movement - it is from his name that the derogatory moniker "moonbat" derives - and if he is finally coming around, then maybe there's hope for others, too. Of course, next it will be some other nonsense ten or fifteen years down the road.

Thursday, April 28, 2011

Fossil Hunter's guide to Mars

I worked directly with Charles Shults as he wrote the book A Fossil Hunter's Guide to Mars, critiquing everything, proofreading, and even came up with the name for the book. So, I am very glad to see that he's getting some mainstream media exposure for his work. When he first told me he had found fossils on Mars in the Spirit and Opportunity images, I was skeptical but at least willing to see the evidence. The clincher for me was this image, taken by the rover Opportunity on Sol 111. In the bottom left corner of that NASA image you see the image at the right. That rock exhibits fivefold radial symmetry. That is, if you rotate that rock in increments of 72 degrees the pattern facing us looks the same. There is no geological process that produces rocks of this kind, no mineral with this kind of symmetry occurs in nature (although such quasicrystals are possible in tightly controlled laboratory settings, they are microscopic). The only way for such a rock to ever appear is if a life form (such as a starfish) becomes fossilized. Therefore, fossils exist on Mars. Not convinced? You can buy the book and check the evidence (presented in exhaustive detail) for yourself.

Saturday, April 23, 2011

Spacex: a man on Mars in ten years

Here's an interview with Elon Musk by the Wall Street Journal. Time frame for a man on Mars? "Best case, ten years. Worst case, fifteen to twenty."

Thursday, April 21, 2011

Delta Robots in LEGO

I love LEGO. The title of this blog might indicate some interest in robots. A few days ago I posted some free software for simulating Canfield Joints in POVray.

So, it pleased me enormously to see the LEGO Delta Robots via Hack A Day.

A Delta Robot isn't exactly the same as a Canfield joint. The parallelograms formed by the arms force the end effector to have the same orientation as the base on top. In contrast, a Stewart Platform behaves more like a Canfield joint, in that the end effector's orientation can be different than the base.

The beauty of the Canfield joint is that two such joints connected in series can act as either a Delta Robot or a Stewart Platform, with loads evenly distributed no matter what the orientation.

Here are some more videos of commercial Delta Robots in action:

Sunday, April 17, 2011

Carnival of Space 193

Welcome to the 193rd edition of the Carnival of Space.

We'll start out the Carnival with the most exotic objects in the universe: Black Holes. Last week's host Vega 0.0 explains the main features of a Kerr black hole.

Discovery Space news tells of a new visualization tool that helps to model the extreme nature of spacetime in colliding black holes.

Is it possible for life to exist within a black hole? Next Big Future says that it's possible.

Moving to only slightly less exotic objects, astroblogger Ian Musgrave looks for Nibiru while explaining some practical astronomy.

On the Road to Endeavour there is an eerie synchronicity in two photos, one taken on Mars and the other on Earth.

Closer to home Next Big Future has news of Moon Express, a Silicon Valley startup building robots capable of mining the surface of the moon for precious metals and rare metallic elements.

In other space commerce news, Urban Astronomer cheers on SpaceX for winning the contract to launch the next generation of Iridium satellites.

For a bit of space history, Vintage Space talks about the Saturn V - its genesis and why it was "lost".

Finally, Steve's Astro Corner looks through a Galileo telescope at Saturn, with surprising results.

That's it for this week's Carnival of Space. Carnival #194 will be held at the Planetary Society blog; if you want to be involved you can either send your entries to Emily at PSB or enter them in the Carnival of Space articles spreadsheet at Google Docs.

Saturday, April 16, 2011

Canfield Joints in POVray

Last June, Kirk Sorenson wrote a blog post at Selenian Boondocks about Canfield Joints. These devices enable pointing a rocket nozzle or solar panel anywhere within a hemisphere.

Part of the problem he had in describing the Canfield Joint is due to the fact that the thing operates in three dimensions, making visualization difficult with 2-D images. Over the last several years I've been using POVray to do 3D designs and animations, and I realized that a character skeleton system I published last year ( would also work well for Canfield Joints.

So, I did a little math (OK, a LOT of math) and came up with a short POVray program that can do 3D animation of Canfield joints. The program is included in the zip file, and the results are shown in the video below.

Given the three base angles for a Canfield joint, the software automatically calculates all the rest of the angles and the position and orientation of the distal plate. An arbitrary number of Canfield joints can be linked in series and manipulated. Now anyone with POVray can design and visualize their own Canfield joints in operation.

Wednesday, April 06, 2011

Artificial Intelligence 101 - part 3

History of AI - from Golems to Dartmouth

It has been way too long (two years!) since I started this series, and I figure it's time to get back into it. For a refresher, here's part 1 : What is intelligence? and part 2: Why Artificial Intelligence?

What follows is by no means a definitive history of artificial intelligence. In fact, Wikipedia already has a very good entry on the history of artificial intelligence. Instead, this is a fairly brief history, with large gaps. I'm a bit more free to editorialize than Wikipedia.

distant past

Humanity has long searched for ways to get the benefits of human intelligence, without the requirements for actual humans. For most of human history, the solution was slavery - treating other human beings as if they were machines, and desiring only a small fraction of their mental potential.

Not only is slavery evil, it is also inefficient - slaves still require water, food, shelter, clothing, none of which is free. Automation of even the simplest sort is so vastly more efficient, along any metric one uses for comparison, that as soon as a task could be automated, it was.

The desire for intelligence in the inanimate has persisted through recorded history. The Golem is a fairly early example, and a cautionary tale as well. From Wikipedia:
The most famous golem narrative involves Judah Loew ben Bezalel, the late 16th century chief rabbi of Prague, also known as the Maharal, who reportedly created a golem to defend the Prague ghetto from anti-Semitic attacks and pogroms. Depending on the version of the legend, the Jews in Prague were to be either expelled or killed under the rule of Rudolf II, the Holy Roman Emperor. To protect the Jewish community, the rabbi constructed the Golem out of clay from the banks of the Vltava river, and brought it to life through rituals and Hebrew incantations. As this golem grew, it became increasingly violent, killing gentiles and spreading fear. A different story tells of a golem that fell in love, and when rejected, became the violent monster seen in most accounts. Some versions have the golem eventually turning on its creator or attacking other Jews.
The Zombie - no, not the Night of the Living Dead type, the Haitian voodoo kind - is a similar cultural expression of this desire for (partial) human intelligence animating human bodies. In both the cases of the Golem (an artificial creature) and the Haitian Zombie (a person enslaved through artificial chemical means and cultural expectations) the desire for control of a portion of human-like intelligence to perform tasks is evident.

Mary Shelley's Frankenstein is another example - a not-human (because he's dead) is re-animated under the belief that the mind could still function. Once again this fictional creation of artificial intelligence is a cautionary tale, as the creature turns on his creator. As an aside, it is also the inspiration for the subtitle to this blog.

In the late 18th century, the Turk chess-playing machine was a fraud that played off the desire for automated intelligence. A skilled chess player was hidden inside an elaborately constructed table with attached mechanical "opponent", operated by the player inside via levers and gears. So clever was the mechanism for hiding the chess master inside, and so great the desire (on the part of the audience) to believe that it was possible to automate intelligence with levers and gears, that the fraud persisted for decades.

the 1800s

In 1837, Charles Babbage developed the idea of a programmable computer, and a partial first sample of the Analytical Engine, which would have been the first Turing-complete computer had it been finished. Lady Ada Byron became the first computer programmer by writing a program to compute Bernoulli numbers on the Analytical engine. This was an important step, as it proved that some tasks which were once thought to be purely mental in nature could in fact be performed by machines - that calculation could be automated.

Then in 1854, George Boole developed a variation on elementary algebra called Boolean Algebra, operating solely on "truth values" of 0 or 1 rather than on all numbers. This Boolean algebra is the basis for all digital logic.

the 1930s

In 1937, Claude Shannon published his groundbreaking master's thesis, A Symbolic Analysis of Relay and Switching Circuits (available here). In that paper he showed that it was possible to use electromechanical relays to solve Boolean Algebra problems. In 1948 he introduced the idea of the "bit" as the smallest unit of information (among other ideas like information entropy) in the paper A Mathematical Theory of Communication (available here), which is itself the foundation of what we today call Information Theory. He showed that electronic circuits could perform logical operations, and that extraordinarily complex computations could be performed with electronics. Once again, what once had required the intelligence of a human could now be automated.

In 1936, Alan Turing described a thought experiment representing an automatic computing machine; this thought experiment has since become known as the "Turing Machine". In 1948 Turing described the idea as: infinite memory capacity obtained in the form of an infinite tape marked out into squares, on each of which a symbol could be printed. At any moment there is one symbol in the machine; it is called the scanned symbol. The machine can alter the scanned symbol and its behavior is in part determined by that symbol, but the symbols on the tape elsewhere do not affect the behavior of the machine. However, the tape can be moved back and forth through the machine, this being one of the elementary operations of the machine. Any symbol on the tape may therefore eventually have an innings.
Although the physical details are different, the description is identical to the operation of any computer today. Instead of a physical tape being fed through the machine, a memory address is polled and the resulting "symbol" consists of a pattern of low and high voltages on wires, what we think of as the Zeros and Ones in a byte.

If a Turing machine is capable of emulating any other Turing machine, then it is considered a Universal Turing Machine. This led to the idea of a stored-program computer - the stored program being the translation software operating in the background. Indeed, most computers today can emulate pretty much any other computer, and the process usually only requires the appropriate software.

We're not done with Alan Turing yet. Besides groundbreaking work in computational theory, he also turned his attention to artificial intelligence. He devised a thought experiment to determine whether an artificial device was actually intelligent. The Turing Test consists of a human, an AI, and a human judge. The judge has a conversation with both the AI and the human through a teletype arrangement - what we would recognize today as a chat window - and tries to decide which one is the human. If the judge can't figure it out solely from the conversation in chat, then the AI is considered intelligent, according to the Turing Test. It isn't a perfect test, but at least it was a first attempt to evaluate the quality of our efforts towards developing artificial intelligence.

So to recap: there is a historical desire for at least (or only) a portion of human intelligence to perform tasks; it was shown that the task of calculation can be automated, mechanically; calculation and complex logical operations can also be automated with electronics; calculating machines with stored programs can emulate (or simulate) other calculating machines; and it is possible to test a machine for intelligence, at least to a first-order approximation.

the birth of AI as a field of study

The 1956 Dartmouth Conference is generally regarded as the birth of AI. Indeed, the term "artificial intelligence" was coined for the conference and came to be accepted as the name for the new field of study at that conference. The Dartmouth Conference led to an explosion of work in the field that continued until about 1974.

The Dartmouth Conference is a pretty good place to stop this section. The next three parts of this series will look at three approaches to artificial intelligence: neural networks, fuzzy cognitive maps, and genetic algorithms.

Saturday, February 19, 2011

Nautilus-X update

I sent an email to Mark L. Holderman of NASA-JSC, asking him to respond to my last post about the Nautilus-X. Here is his response:
Hello Ed,
Thank-you for taking the time to look at Nautilus and to post the presentation on your site. [I have attached a slightly updated version; there has been some file corruption from multiple downloads]

I apologize for not responding sooner, but for some I/T reason a great many emails have been directed to the Server SPAM file; I now check it regularly.

A great deal of "detail" information is not contained in the presentation. This was by design; it was crafted to be an oral presentation with much of the technical content addressed by the speaker, who directly answers audience questions and can therefore better engage the particular interest(s) of various groups. What you have viewed is the Concept "Sales" package - it attempts to paint a picture that folks might want to find out more about. So questions, observations, critiques, no matter on what subject - and as long as they are more-or-less civil in tone, are all welcomed. If a dialog results, well then --- yahoo!

Your questions about thermal considerations are spot on. While in LEO [construction phase],the classic basting roll maneuver would likely be employed. But transit to L1, and at L1 require a different solution. Most folks don't notice the lack of thermal rejection capability in the Concept images; they are usually taken aback at the general (size) and odd structural manifestation that good engineering details are not usually assessed. Thermal load/rejection and management at L1 will be different than at LEO, will be different than during a CIS-Lunar route [repeated], and definitely different than for an inner Solar System junket[trek...I wanted to avoid that term]. So yes, Thermal management is a major technical consideration that has a couple of nifty solutions that are being pursued. One of the inflatables will have a decidedly green element associated with it....[think Silent Running w/ Bruce Dern]. It is a partial thermal shunt, not the complete solution. Radiators will still be required, along with some new Variable Conducting Heat-Pipes that the old Hughes Aircraft Corporation had utilized.

The "Winnebago" section is new-think applied to the design success of the Apollo LEM. The Lunar Excursion Module is THE most successful spacecraft ever built. Purely and completely a space-craft that journeys in the Space environment. I purposefully exclude ISS, as it is essentially a static platform. Many of its design factors were constrained by the method of its construction --- Orbiter delivery with on-orbit assembly. The OV payload bay is incredible, but it does have both constraints and strong limitations [I am from the SSP]. With that understood, Nautilus design knowingly departed from ortho/iso-grid cylinder construction to embrace the lessons learned from the Grumman "flat-panel" LEM. Load path negotiation was a nightmare back then, and early NASTRAN was an indication of a trend, not even remotely considered an absolute.

The addition of what is called the "exo-truss" to the entire vehicle, for managing and transmitting the Propulsion Pod(s) thrust(and Isp), will give Nautilus sufficient structural integrity. We also hope for hefty a natural frequency so that the Centrifuge can become a positive input into the overall GN&C design.

I hope this helps answer of few of your questions. If nothing else, it is hoped that Nautilus-X is utilized as a development tool/mechanism for good System(s) engineering design and produces some decent axioms for large, long-duration spacecraft design. But it is something of a nifty Concept....

Warm regards,
--- mark

First of all, thanks to Mark for shedding a little more light on this concept. The updated powerpoint (linked above) contains a few more pictures of the Nautilus-X from different angles.

Slide 32 is particularly interesting - an orthogonal view of the "underside" of the craft. It is clear from this slide that the single biggest section is that "Winnebago" at the nose. No other segment even comes close in size - everything else could probably be launched on currently- or near-term-available rockets, but that Winnebago would need something much bigger than we have right now.

I understand they are eager to use the flat panels, drawing from the Lunar Excursion Modules as an inspiration. The slide-out concept might even work just fine. That heavy lift requirement for just that one element is the problem.

If one were to imaginarily slide that command deck back and the big airlock forward, it is easy to see that this one piece could be broken up into three pieces with no slide-outs, each of which could fit on existing rockets.

I agree completely with doing the ISS demo of the centrifuge. We might get lucky with that size centrifuge and find the right amount of spin to reduce or eliminate bone loss without making astronauts dizzy. If it turns out we need a bigger centrifuge, then we've found that out early on. If not, then that's a big hurdle out of the way.

I agree with the external truss framework. It makes lots of sense. The one weak point is at the centrifuge. All thrust loads have to be transmitted through those bearings. I could see having a central truss through the centrifuge taking the load off the bearings, but having that centrifuge located coaxial with the main thrust axis in between the Winnebago and the rest of the ship gives me the willies. It might be better located right at the nose of the craft. Having two centrifuges rotating perpendicular to the centerline might even be better. It isn't clear whether the centrifuge is rotating during any boosting operations; if not, that might simplify the loading during boost.

"Silent Running w/ Bruce Dern" - oh, boy. Bruce Dern also gives me the willies. Kidding aside, I think that having lots of plants and hydroponic food and so forth will go a long way towards improving the life support system of space vessels. Hydroponic gardens are already extensively used by submarine crews around the world, and will surely be useful in long-duration space flight. Just having green growing things around will provide a psychological boost to the astronauts, but their primary use would be to help replenish the oxygen supply and to provide food. I'm all for it.

The more I look at the solar panel arrangement, the more convinced I am that the booms should be longer, and that there should be Canfield joints between the booms and the solar panels. The mechanism is far less complicated than the SARJ used on the ISS, and would allow a full hemisphere of aiming for each solar panel.

Saturday, February 12, 2011

NASA designs an actual spaceship

The Nautilus-X MMSEV is the closest NASA has come to a design for an honest-to-goodness spaceship in decades. There has already been extensive discussion over at Selenian Boondocks and Hobbyspace, and this is probably a couple weeks late on the subject. However, this is an idea that has considerable merit and deserves further study. So, I uploaded the Holderman powerpoint to Google Docs, and here it is:

If you click on the "open in new window" button, then you can view it in full screen.

There is a lot that I like about this design - in fact, much of it looks like items on my list of technological stepping stones to space. For one thing, it is modular. Yes yes absolutely yes. Several launches are required to put it together, all of which could be done with existing vehicles (with one exception which I'll get to later). It includes a centrifuge, which might mitigate some of the bone loss effects of microgravity. It includes inflatable modules. Above all it is a spaceship - its environment is space, it has no landing gear or reentry heat shield.

Now, there are some things I don't like about the Nautilus-X.

That big core section would require a single launch, probably on something heavier than anything in stock today. It has RV-style slide-outs for the command deck and a large airlock. Worst of all, it has flat walls - probably due to the slide-outs. The flat walls and slide-outs are brand-new technology that introduce unnecessary failure modes and complexity. This could be redone as two pieces with curved walls: the radiation mitigation chamber is one piece, the airlock and command deck are another, set "sideways" to make a T shape. These two smaller pieces could then probably be launched on existing launch vehicles.

The centrifuge radius is an educated guess. We don't know the minimum gee required to reduce or eliminate bone loss. That particular centrifuge would produce no more than a few percent of a gee (i.e. about lunar gravity at 4RPM by my estimate) before problems due to high angular velocity start to occur. If a few percent gee is enough to slow or stop bone loss, great! If not, then this centrifuge would be an added layer of complexity for limited benefit. There would be benefits, no doubt, particularly for things like eating and ablutions, but the primarily-intended benefit would be missing. The bearings on the centrifuge - allowing nearly frictionless rotation while not allowing atmosphere to escape - are going to be a novel engineering challenge.

The MMSEV is intended for very long duration missions, up to two years. Unlike satellites in low earth orbit, which spend half their time in Earth's shadow, the MMSEV would be out in cislunar space or interplanetary space constantly being exposed to the sun. The entire craft would have to do a slow "barbecue roll" to avoid overheating one side, most likely along its long axis in the opposite direction of the centrifuge. Canfield joints at the end of the beams holding the big solar panels would allow them to continuously track the sun during the barbecue roll.

It's a good start.

Update Mark Holderman responds.

Monday, January 24, 2011

demolishing global warming

The theory of anthropogenic global warming (AGW) is based upon the following principles:
  • the global climate is changing
  • carbon dioxide content of the atmosphere is increasing due to human industrial activity
  • the increase in CO2 concentration increases the amount of heat trapped in the atmosphere
  • this could cause a runaway effect making the earth uninhabitable
This is all presented as though it is established fact, and that the obvious conclusion is that we must greatly decrease the amount of industry worldwide -- achieved through regulation, internationalism, and so-called "green" activity.

But what if one of those principles above is wrong? What if CO2 concentration is not correlated to average global temperature? What if the current variation is in fact insignificant?

The glaciers of Greenland have yielded thousands of ice core samples to scientific survey. Significantly, the Oxygen-18 isotope concentration in the ice is a good proxy for average global temperature over a long timescale. A water molecule containing O-18 is 11% heavier than the O-16 water molecule, so it takes more energy to get a water molecule containing O-18 to evaporate into the atmosphere than it does for O-16. This heavier isotope is more abundant in the snow when the temperatures are warmer, and less abundant when it is colder globally. The ratio of O-18 to O-16 in the ice corresponds to a temperature at ancient glaciers in Greenland - a yearly average high-resolution record going back over 100000 years.

Dr. Don J. Easterbrook has an analysis of these ice core samples, analyzing the rates of change of temperature:
Temperature changes recorded in the GISP2 ice core from the Greenland Ice Sheet show that the magnitude of global warming experienced during the past century is insignificant compared to the magnitude of the profound natural climate reversals over the past 25,000 years, which preceded any significant rise of atmospheric CO2. If so many much more intense periods of warming occurred naturally in the past without increase in CO2, why should the mere coincidence of a small period of low magnitude warming this century be blamed on CO2?
So that about does it for anthropogenic global warming.

Update: Here's another view, looking at ocean sediments, providing a temperature reading dating back 65 million years. And here is the GISP2 data; see for yourself.

Sunday, January 16, 2011

civility in politics?

Ya gotta be kidding me. After eight years of reading about Chimpy mcBushitlerburton? After seing how the Left conducts demonstrations (oh yeah, all those balaclava-garbed idiots throwing firebombs at G20 meetings are "anarchists"), Obama's frequent threatening tone ("... so we know whose ass to kick"), and an incident where Sara Palin was hung in effigy ("For weeks the life-size mannequin of Republican vice presidential nominee Sarah Palin that hung from a noose around its neck in front of Morrisette's West Hollywood home caused little controversy.")- now you want civility?

Lemme tell ya something, princess. Politics ain't ever been civil:

update the next day: remember this from just a few months ago? I could probably dig up a hundred more examples if I wanted to.

I'm with Don Surber. Bite me.