Topic: Modest space project idea: Lets make a planet.

[Nemesis]

A resurrection of Stormbringer's old thread.

What if we send a fleet of self replicating robotic tugs, solar collector oven satellites and ancilliary equipment to the asteroid belt. They would manuever asteroids into proximity of one another then weld or melt them together until enough mass was accumulated to cause gravity to finish the work of constructing a terrestrial core approximately the same size as the earth's core. Then carbonaceous or nonmetalic asteroids could be processed to form a mantle and finally a crust. The protoplanet could be constructed in such a way that it's solar orbit could be stable and it's spin rate could be controlled as it is built up so that it could be near the earths. Either the original fleet working in the asteroid belt or another dispatched to the ort and kuiper belt could use the materials there to pelt the dry planet with water and gases to become an atmosphere. The gas mixture could be altered so that the distance from the sun is mitigated by greenhouse gases. The limited but self replicating fleet could enable this be done in an amazingly short time (relatively speaking.)

This would have several benefits.

Firstly it would get rid of most of the larger earth endangering debris in the solar system.

Secondly it would in due time give the burgeoning population somewhere nearby to go to.

Thirdly it would develop a knowledge base for terraforming and environmental disaster control. It would spare the existing planets from the environmentalist controversy likely to ensue if someone decides to terraform Mars, Venus, Titan or other worlds. (this would destroy any chances of finding either life or evidence of past life on those worlds.)

The only thing I'm not sure in regards to constructing a planet are in regard to creating the dynamo needed to create a molten core necessary for a magnetosphere. 

[Nemesis]

A problem with his plan - not enough asteroidal mass.

Link to source of quote below

It has been estimated that the total mass of the Main Asteroid Belt may total less than 1/1000th of the mass of the Earth. Indeed, if all asteroids down to the size of meter- or yard-sized boulders or less were combined together, the resulting object would measure less than 1,300 to 1,500 km (810 to 930 miles) across, which is less than one third to one half the diameter of the Earth's Moon. The Main Asteroid Belt is only a small remnant of the material that once resided in the region between Mars and Jupiter, but once may have contained between two to 10 Earth masses of material (Dan Durda, "Ask Astro," Astronomy, December 2000). However, T-Tauri-type Solar winds from a very young Sun, gravitational perturbations from Jupiter developing nearby, and dynamic interactions with other large planetesimals and protoplanets during the first 100 million years, and continuing collisional grinding over the following 4.5 billion years after the formation of the planets, interfered with the formation of a substantial, single planet and caused most of the mass to be lost to the rest of the Solar System and interstellar space.

An alternative mass source would be required.

Instead of planet building, space habitats could be substituted.

Travel to and from his proposed planet between Earth and Mars could use the cycler concept (link to cycler info).  Limited information on cyclers in the quote below.

Modified versions of the space shuttle's external fuel tank might be used as building units for cyclers. The tank ordinarily is jettisoned during shuttle flights, and it burns up in the atmosphere. However, the shuttle's external fuel tank could be modified, adding two additional empty tanks atop the existing fuel tank. Instead of being jettisoned, the modified external tank assembly could then be carried by the shuttle all the way to low-earth orbit, where the dry tanks could be separated from the main tank and used to construct the spacecraft.

Cyclers would take advantage of the gravitational forces that are exerted by the sun, the planets and their moons, which provide "gravity assists" to passing spacecraft. As a spacecraft travels close to a planet, its flight path is bent, causing it to whip around the planet while boosting its speed. The path is commonly called a "slingshot" trajectory, which enables a spacecraft to achieve the proper speed and heading.

"The cycler essentially is in orbit around the sun and makes regular flybys of Earth and Mars," said team member James Longuski, a professor of aeronautics and astronautics at Purdue. "Once you put your vehicle into a cycler orbit, it continues on its own momentum, going back and forth between Earth and Mars. You may need to carry some propellant for an occasional boost, but it's pretty much a free trip after that."

[Javora]

Sheesh, almost makes building the Death Star sound easer.   

[Stormbringer]

Hi guys! The estimated mass available in some form or another is rapidly going up. what is it, three now trans-Pluto planetoids like Sedna? And the sunward asteroids numbers are increasing also though they are hard to find. add to that god knows how much dust...not to mention already formed planets and planetoids that could be altered like mars venus, titan, triton. I still think it is doable.

[Stormbringer]

Also, I recently exchanged Email with a planetary scientist after reading an article he had published on computer modleing of extra solar planets around binary stars. we talked about safe orbital tracks in our own solar system he said that just about any area out to but not including the asteroid belt would provide a stable orbit that would not break up a planet or endager existing planets. So this proposed synthetic planet could easily live in the habitable zone of the solar system.

[Stormbringer]

I E mailed the professor in the story about habitable zone terrestrial planets and he replied back. Here is what we talked about (his replies are in blue) he quoted my original e mail and answered by inserting his answers in my e mail's text.
Professor Jones;

I enjoyed your article on exosolar terrestrial planets recently carried by space.com but it got me thinking about a question i have had from time to time. I'll be brief; Are there stable orbital tracks in out solar system which are unoccupied?if so can you provide me with data on this question. for example; are the conditions that prevented a planet from forming in the area of the asteroid belt likely to have abated by now? would some sort of gravitational tide tear a planet apart if it was put there?

There are many tracks in the Solar System that offer orbital stability and that are unoccupied. The asteroids are in a zone where the gravitational buffeting by Jupiter prevented the formation of a planet, and still does so. This buffeting also prevented Mars from becoming as large as the Earth. But any planet somehow put there fully formed would not be torn apart.

I have layman level discussions on this from time to time concerning megascale engineering. creating a planet to match as closely as possible all earth like parameters such as temperature range, atmospheric pressure, magnetic field, gravity and so on. I have determined enough material is probably left in the solar system at various places like the asteroid belt, kuiper belt and oort cloud and the earth crossing near sun objects to equal earth's mass density and therefore gravity. I have worked out ways of controlling the spin.

The total mass today in the asteroids is insufficient to make a planet of any size. The Edgeworth-Kuiper belt and the Oort cloud could beef this up to a planet, but to be habitable all this material would have to be assembled in the habitable zone, which doesn't extend far beyond Mars. The stunted growth of Mars has led to loss of much of its atmosphere, so its surface is not habitable today.

I would appreciate your ideas on this subject. particularly since your article mentioned computer modeling to determine stable orbits around another sun it should be easy to run that model on our own system here. Thanks in advance.

You can assume (to a first approximation) that anywhere closer to the Sun than the middle of the asteroid belt is likely to offer stable orbits, with narrow zones of exception, such as near Mars, the Earth, Venus, and Mercury. The habitable zone extends today from just beyond the orbit of Venus to just beyond the orbit of Mars.

[Stormbringer]

I wonder if enough radioactive elements could be injected into the core to keep it molten like earth's core without accidentally reaching supercritical density and blowing it up like a planet sized atomic bomb?

[Javora]

Mars already has the orbit and the spin, it just needs more mass.  Wouldn't it be easier to bombard Mars with asteroids then hit the planet with a few nukes to warm the planet up?  It seems that since Mars is a lot closer to the size we need than a few large asteroids combined, it would expend a lot less energy to create what we need in the long run.

*Shrugs*  Just a guess.

[Stormbringer]

Mars already has the orbit and the spin, it just needs more mass.  Wouldn't it be easier to bombard Mars with asteroids then hit the planet with a few nukes to warm the planet up?  It seems that since Mars is a lot closer to the size we need than a few large asteroids combined, it would expend a lot less energy to create what we need in the long run.

*Shrugs*  Just a guess.

Indeed it would. In fact that was one of my earlier suggestions, but-   I thought afterwards that some enviromental activist's would object as would some scientists and the fringers who believe there might be alien archaological finds there. And now it looks like there might be some life there in the form of extremophile bacteria and other simple organisms. If mars were to be resupplied with gases from icy comets it would take 16 million years for the renewed oxygen to escape. many times longer than the entire history of mankind. that's assuming we did not go ahead and increase the rocky mass so that it could not escape at all. It would be the way to go if the critics were ignored.

[Javora]

It seems like it would be faster on both counts if we used the ice on Earth's moon instead of using comets.  But then we will need that ice to get us deeper into space.  The bacteria on Mars could be a double edged sword, while it could be usefull in scientific study it could also be very deadly to humans.  So nuking Mars may not be all that bad and I doubt that Mars was ever populated by any intelligent life form.  Despite what the Globe puts out every other month about reporting that Elvis's face is on the serface of Mars.    

[Stormbringer]

Yeah but the scientific value of studying the first extraterrestrial lifeform even a microbe is a very serious matter. if thye find them and i think they will it nixes the type of engineering we were talking about for a considerable amount of time. perhaps forever. While making your own planet has none of the enviromental and biological pitfalls of reengineering mars. Heck even venus is really a better prospect than Mars because it has the same gravity as Earth, has the proper elements and it's heat problem can be overcome by altering the atmosphere and eliminating the sulphuric acid. tuning the atmosphere the right way could lower the temperature to earth like levels. If not then large "mylar" reflectors could be orbited to shade it and reflect away sunlight.

[Stormbringer]

UIsing the moon is a no no. doing so would devastate the earth. Earthquakes, volcanos, floods, tsunamis, storms, dogs and cats living together; mass hysteria!

[Javora]

But wouldn't the orbit of Venus have to be altered as well?  It seems like that would be harder to do and still keep the spin rate at the same level that Venus is now.  Sounds like a great idea though.

[Javora]

UIsing the moon is a no no. doing so would devastate the earth. Earthquakes, volcanos, floods, tsunamis, storms, dogs and cats living together; mass hysteria!

 


I was just talking about the ice on the moon's surface, not ripping the moon out of Earth's orbit and smashing it into Mars. 
But the ice on the moon could probably be better used as rocket fuel.

[Stormbringer]

Not necessarilly. a great deal of venus's heat problem is due to runaway greenhouse conditions due to compounds like sulfuric acid in her atmosphere. with the removal of those compounds and the addition of compounds or gases that do not trap heat well the temperature could be lowered to earth norms. just as mars temperatures could reach earth norms with the proper atmosphere. the highest recorded summer temperature on mars is 80 degrees F. which is quite acceptable to humans. Venus could be further cooled with large scale reflectors in orbit around her. However moving her would be a good idea and it would not effect the earth in any way. right now we don't have the means to move a whole planet but in the future we might. A russian scientist has had some success with antigravity research. he became famous for reducing the apparent weight of masses with superconducting disk magnets. Since then he has apparently managed to create a gravity and antigravity beam and his work has been taken up by thousands of amateur enthusiasts.  

[Nemesis]

But wouldn't the orbit of Venus have to be altered as well?  It seems like that would be harder to do and still keep the spin rate at the same level that Venus is now.  Sounds like a great idea though.

Actually the current day on Venus being 243 (Earth) days long I think that to terraform it we would either want to spin it up or use reflectors to simulate a 24 hour day.   Oddly enough on Venus the sun rises in the West and sets in the East.  Venus rotates backwards compared to the other planets and its own orbital direction.

Link to Venus Info

[Stormbringer]

yep. you pointed that out in the old thread too, i think.

[Nemesis]

UIsing the moon is a no no. doing so would devastate the earth. Earthquakes, volcanos, floods, tsunamis, storms, dogs and cats living together; mass hysteria!

As you say Doctor Venkman.  But that only applies if we move it or change its rotation.  It could have air and water added and reflectors to change the apparent day night cycle to a 24 hour period. 

Even a pressure of say 3-7 PSI of non breathable/non corrosive and not toxic (in small quantities) atmospere would make using the Moon much easier.  Flight using aircraft rather than rockets would be possible even balloons or Zepplins would be practical.  Aero braking for landing of space craft (and water landings) would reduce fuel requirements.  Pressurized habitats would have to worry about leakage out rather than explosive decompression.  Minor to semi major leaks would not be the disaster they are with a vacuum outdoors.  No pressure suits only an O2 tank and face mask would be needed (plus heat or cold protection depending on local temperatures). 

[Nemesis]

yep. you pointed that out in the old thread too, i think.

I looked and could not find it.  Maybe in a related thread.

[Stormbringer]

Check this fringer site out. it has some info on Dr. podkletnov's gravity research. But don't letthe fringe site throw you the dr's credentials are real and his research is published and was covered in the mainstream media. Heck boeing, NASA and others have shown interest.

http://www.americanantigravity.com/podkletnov.html

[Nemesis]

I have come across it before.  So far it seems to be "unvalidated".  Anything that can manipulate gravity in any way would be of amazing importance both scientifically and technologically.  One must hope that he is right and that it can be developed.

If it can be proven and the effect magnified in a portable fashion then the rules of transportation systems could easily go totally out the window.   Lower your personal gravity and the fantasy of Icarus becomes real. The Moller skycar would be obsolete before it hit the market. 

Even material processing could dramatically change.  There are materials that in theory could be made in zero or microgravity far more efficiently than in the Earths 1g field.  The ability to create a 0g field on the surface of the Earth would allow those processes without having to travel to space and operate in vacuum conditions with all the equipment in 0g.   

Pumping by changing the gravity field would avoid damaging materials as can occur with current pumping systems.  It would also allow leak free pumps as the gravity controller responsible for the pumping action would not need to be in contact with the material being pumped.

Of course gravity control on a planetary scale would make moving Venus and other bodies easy.  Even spinning up Venus would become doable.  You space project would become modest.

[Stormbringer]

All true. i note however that the reason NASA was not able to replicate was that they refused to follow his protocol for the original experiment. They have subsequently agreed to retry the experiment using his protocol. I do not know the deal with boeing's work. But the good doctor is not alone in postulating gravity coupling with superconducting magnets.

[Commander Maxillius]

I would say Venus would be the best bet at terraforming.  Venus is the closest to Earth's gravity, and the only thing standing in the way of a normal atmosphere is that there's so much of it.  If we could blow the atmosphere off with nuclear devices so that the spin could be affected at the same time, Venus could have the opportunity to cool to temperatures at the equator of around 150ºF a mere hundred years later.

Nuclear devices wouldn't have the ability to reverse the spin and speed it up enough to give it a day less than half a year, but Venus will need water, so tossing comets at it will help to accelerate the spin to at least a 30-hour day. 

Then the only thing we'll have to worry about is the psychotic effect of the huge sun in the sky!

[Stormbringer]

yes using venus does eliminate the primary problem of gathering enoguh mass to equal earth's mass/gravity. the other problems require no fundamental breakthroughs providing we do not have to move her. Nukes however would be too small to blow away the atmosphere. the most logical way of altering the atmosphere is through chemistry and catalysts; either biological or mechanical. for example if microorganisms are developed that feed of sulfuric compounds they would reproduce as long as there was sulphuric compounds in the air. they would reproduce exponentialy as long as the supply was optimal then die off as the level becomes less than optimal. since they grow exponentially they can rapidly eliminate most of the sulpuric acid and any hydrogen sulfides. thier biology could be taylored to bind the sulphur to metals or other heavier than air material. the same could be done for other compounds or elements. if that is insufficient we could super heat the top layer of the atmosphere with lasers or mirrors. the increased kinetic energy would kick many more atoms and molecules out of the gravity well than would normally occur through random brownian motion. in this way the exess atmosphere could be antenuated down to earth norms.

[Nemesis]

We need an advanced ION drive that can use the atmosphere of Venus as reaction mass then use the drives (1000's all over the planet) to spin up the planet and remove unwanted atmospheric components.  Bombard it with comets at the same time to provide more material for spinning up and building an atmosphere/hydrosphere of the "right" types.  Of course ideally we should move Mercury out to be a Venusian moon. 

[Commander Maxillius]

Mercury's very dense.  It's got a solid iron core that's I think larger than Earth's, but total size only slightly larger than our moon.  Putting mass like that in orbit of Venus would only slow her down further.

[Stormbringer]

I'd assume that with a highly eccentric orbit it could be used to actually speed it up but any technology that could move mercury would easily be able to spin up venus.

[Commander Maxillius]

It would be far cheaper to mine Mercury's core where it is than to try to move it anywhere.

[Nemesis]

A planet named for a goddess of love needs a lovers moon.  Mercury is ideally large. 

Besides I want tides in my oceans I don't want them stagnant. 

[Commander Maxillius]

good point, but Mercury's far too massive for that.  Your tides will be huge and the tidal forces will eventually make the whole surface volcanic.

Better to build a Death Star moon or something hollow like that.

[Nemesis]

good point, but Mercury's far too massive for that.  Your tides will be huge and the tidal forces will eventually make the whole surface volcanic.

Better to build a Death Star moon or something hollow like that.

Put it a little further out. 

[Sirgod]

Magma oceans sloshed across early asteroids

    * 18:00 15 June 2005
    * NewScientist.com news service
    * Jeff Hecht

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Some asteroids, such as the 52-kilometre-long Ida, may have been melted by radioactive isotopes when the solar system was forming (Image: NASA)
Some asteroids, such as the 52-kilometre-long Ida, may have been melted by radioactive isotopes when the solar system was forming (Image: NASA)
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Web Links

    * Richard Greenwood, Open University
    * Michael Drake, University of Arizona
    * Nature

 

Oceans of molten rock, or magma, covered some asteroids in the early solar system, reveals a new study of meteorites. But researchers are still puzzled over why other asteroids apparently did not melt at all.

In the solar system's first few tens of millions of years, collisions between rocky objects and the decay of radioactive isotopes melted the interiors of large objects. Magma oceans - perhaps hundreds of kilometres deep - lapped over the Moon, the Earth, and other planets, allowing dense material to settle towards their centres in a process called differentiation. But the extent of asteroid melting had remained unclear.

Now, Richard Greenwood at the Open University in Milton Keynes, UK, and colleagues have analysed groups of meteorites thought to have come from the 530-kilometre-wide asteroid Vesta and from a second, still-unknown, asteroid.
Short half-life

They found all of the meteorites from each source shared the same ratios of oxygen isotopes, suggesting both asteroids must have melted almost completely. "It's an exquisite piece of work," says Michael Drake, a geochemist at the University of Arizona in Tucson, US.

But the research fails to explain why other asteroids do not show any evidence of melting. Ceres, the largest known asteroid - 930 kilometres wide - appears to be totally undifferentiated.

Drake thinks the difference may be down to timing. Previous research has suggested asteroids were heated by the decay of radioactive aluminium-26 in the dusty disc from which the solar system condensed. That isotope has a half-life of only 700,000 years. So if it was the main heat source for the first asteroids, too little may have remained to warm those that formed later, Drake says.

Journal reference: Nature (vol 435, p 916)


question:  How much remaining radioactive material is available? enough to produce an earth sized molten outer core? Thinking magnetic fields here...

[Sirgod]

An Ad Astra terraforming article via space.com:

 Terraforming: Human Destiny or Hubris?
By Dave Brody

posted: 17 June 2005
09:40 am ET

This story first appeared in the Spring 2005 Issue of Ad Astra Magazine

 

"Men are weak now, and yet they transform the Earth's surface. In millions of years their might will increase to the extent that they will change the surface of the Earth, its oceans, the atmosphere, and themselves. They will control the climate and the Solar System just as they control the Earth. They will travel beyond the limits of our planetary system; they will reach other Suns…”

Konstantin Tsiolkovsky c.1926

 

Say the word “terraforming” amidst a gathering of space enthusiasts and it’s a bit like upending your beer mug in an Australian pub. It means you’re ready to duke it out with anybody in the joint. And the fight usually breaks out along these lines: One team sees the quest to replicate the biosphere of Earth on other planets as a moral imperative, an inevitable destiny, or both. Others -- equally passionate -- recoil at such pretension, proclaiming with surety that humans have no right to interfere with Nature as writ large upon the face of other worlds. Both viewpoints are, of course, so fraught with self-defeating conflicts as to be, well, flat out wrong.

 

Weird, isn’t it, that an enterprise that no one now alive can remotely hope to see fulfilled should arouse such fire and fury? [Nobody quibbles much about warp drives, wormholes or what we’re actually going to reply to ET.] But there seems to be something about the notion of taking a planet upon whose surface you did not evolve and changing it to suit yourself that catalyzes all audiences immediately to one pole or the other.

 

Bind yourself to the nearest mast and try to listen dispassionately to the combatants and you’ll start to hear these discussions for what they really are: religious conflicts. Disagreements rooted in faith, belief and longing. What you won’t hear, usually, is good science. Not often sound engineering tips. And not much of immediate practical use to those of us who want to expand Humankind’s range to include the resource base of space, a primary goal of the membership of the National Space Society.

 

Equally odd, if you think about it, the terraforming tirades seem to swirl solely around Mars. The asteroids are much easier to work with. Earth’s Moon is closer, better known and sports a more fun-friendly gravity field.  Europa, and (likely) other moons of the gas giants, may have lots more liquid water and could harbor more complex life.  Comets have mega-tons of water and organics and they visit us predictably. And, as long as we’re talking technology that doesn’t yet exist, we might imagine (as Carl Sagan, and a generation of science fiction writers before him, did) thinning and cooling the atmosphere of Venus -- a virtual twin of Earth in size and mass -- as least as easily as we could cause a thicker and warmer atmosphere to magically stick to the low mass of Mars. [See Randa Milliron’s excellent article in the winter 2005 issue of ad Astra.]

 

Yet Mars is where the terraforming battle rages now. So let’s face it.

 

Designer Worlds

 

“Can we do it? We’re doing it on the Earth,” argues Jim Bell, lead scientist for the Mars Exploration Rovers’ PANCAM, “We’re changing the Earth’s atmosphere whether we realize it or not. It’s certainly within the realm of a reasonable extrapolation of future technology to think we can do it on Mars. Must we do it? I don’t think that’s our call. I think that’s the call of the people who are living there a hundred years from now, living in spacesuits, dealing with this gritty dust that’s all over the place, having to manufacture oxygen from rock or ice underground.”

 

Not everyone wants to wait that long: “We have the capability now of being the pioneer species that can go out to a currently barren island out there on Mars and make it habitable for life,” declares engineer and author Robert Zubrin. “Really, what humans are doing is, in a sense, fulfilling an obligation on behalf of the terrestrial biosphere.”

 

Gaia Weighs In

 

There is a notion -- strangely, embraced by both ultra-liberal tree huggers and rabid reactionary exploiters -- that the Earth is somehow a self-regulating über-organism. This idea implies that Terra’s vast mass and complex biosphere will adapt to human-induced alteration in a manner that is ultimately favorable to that biosphere as a whole system (though not necessarily good for humans). But why would it be that Earth can do that, while Mars seems to have “areo-formed” itself from a warm wet world to a cold, dry barren wasteland? As Jim Bell puts it: “How do you go from an Earth-like place, to a Mars-like place?”

 

That is a central question behind the current Spirit/Opportunity missions. And their Principal Investigator, Steve Sqyures, has this to say about terraforming: “We are very far from being able to control -- or even fully understand -- the climate of our own planet. And I think that changing the climate of an entire planet in an intended direction, getting an intended outcome and betting people’s lives on that outcome strikes me as a chancy proposition for the foreseeable future. It sounds like a tough thing to do.”

 

Perhaps this whole business may turn out to be about simply taking control of the pace of biological  change  rather than about redirecting towards or away from Earth’s biology.

 

Astrogeophysicist Chris McKay, one of the first scientists to look seriously into the notion of purposefully guiding the biological evolution of Mars  -- and one of the founders of the so-called Mars Underground -- thinks of a Red Planet re-engineered, but for the original residents. “If there is life on Mars, it's not doing very well. We know that from just looking at the planet. And it could use some help,” McKay believes. “I think we would be ethically on good grounds to support it, to encourage it to flourish into a global scale biota like we have on Earth, especially if it was on the verge of extinction which it could well be.”

 

McKay would champion a technological effort to nurture these, presumably microbial, or at least miniature, Martians: “They would have the right to evolve on their own biological trajectory. Although Mars is a very interesting world without life, my own personal judgment is that life is a more intrinsically valuable, beautiful phenomena.” Chris McKay perceives a marked difference between warming the planet up to support simple, stupid life and fully engineering a human-shirtsleeve balanced Nitrogen/Oxygen atmosphere at water cycling temperatures. On McKay’s Mars, the first is possible and desirable; the second is not.

 

To do either requires giving the rusty red world a much thicker atmosphere. Mars atmospheric scientist Scot Rafkin isn’t sanguine about that possibility: “I think it would be tough. And more than the technical aspect, you have to wonder how expensive it would be versus, say, enclosing huge regions of Mars and modifying the environment for human habitation. It might make more sense to do that than to try and add significantly more mass to the entire atmosphere.”

 

“Life on Mars probably died out young when the planet went through this transformation to a thin, cold atmosphere,” says planetary scientist David Grinspoon. “There’s nothing about the ancient past of Mars that was so different from Earth that the origin of life should not have happened. I think it’s quite reasonable to look for fossils on Mars (but) in my opinion Mars at present is dead, dead, dead.”

 

Lacking any other examples of life in the Universe, there’s no denying that Earth life’s propensity to begat more life is spectacular. “The fundamental policy of life is one of talking barren environments and transforming them into those that are friendly to the propagation of life,” opines Mars Society founder Robert Zubrin. “That is why we have oxygen in Earth’s atmosphere and why there is soil on Earth’s continents. It’s an artifact of life. Symbiotic communities of plants and animals have transformed the Earth.”

 

Earth life and Mars life could be rooted in the same DNA. Or they could have had independent origins. “The question of going to Mars if there are, in fact, Martians – even microbes – is a question that tends to be glossed over by people that are really excited about the idea of going to Mars,” David Grinspoon adds. “The good news is that there aren’t Martians, I’m pretty sure. But we have to be a lot more sure before we go starting to set up our strip malls and sports stadiums.”

 

Given our track record of modifying Earthly environments, can we safely conclude that Nature has pre-destined -- or at least deputized -- Homo sapiens to be the agent of its spread to the stars?

 

Again, Bob Zubrin: “Human beings in bringing life to Mars will be, in a very real sense, continuing the work of Creation. We will not be playing God but engaging in that activity that God gets the most credit for doing. By so doing, we will show the divine nature of the human species and, therefore, the precious nature of every member of it. No one will be able to look at a terraformed Mars and not be prouder to be human.”

 

Designer Humans

 

Ah, but what is a human in this brave new Universe? Though the specifics are fuzzy at best, no one disagrees that true, deep change of an entire planet -- Mars or any other -- will take “a long time.” Our great-great grandchildren may find that it is easier to reshape and supplement people to live on varied worlds than it is to rework those worlds for the sake of people. The bio-memetic revolution is just now being born. And it may seem to its beneficiaries, a few generations hence, that the idea of altering an entire globe to perform like Earth is rather like Michelangelo depicting God as a great white, corpulent, male, cloud-floating human. It’s a great work of art, but it now seems awfully exclusive and faintly embarrassing.

 

Could be our concern here ought not to be for what our descendants will think of us for having contemplated terraforming, but rather what the terraformers’ progeny will think of them for having actually done it. Heady stuff.

 

Next page: The Designer’s Galaxy

[Sirgod]

Part 2:

The Designer’s Galaxy

 

One way to keep one’s sanity inside a terraforming discussion is to remember why one wanted to set sail for space in the first place. Perhaps the most compelling reasoning for grabbing a toehold beyond Earth was articulated by Greg Allison within these pages a few months ago:  survival, not just of we the “smart monkeys” but of Earth’s complex and explosive ecology.

 

“If you’ve got an endangered species, you don’t want to have just one little plot of it someplace,’ says David Grinspoon. “All life on Earth is that endangered species. If we get to that stage where we’ll be moving from one celestial body to another, we’ll have a pretty good crack at outliving the Sun. We may be manning the lifeboats, but in those lifeboats there will be all the species of Earth coming with us (well, maybe not the mosquitoes).”

 

We space enthusiasts have felt this push for a long time. Konstantin Tsiolkovsky, the Russian space visionary, began to build out a sensible strategy for populating the galaxy while the Wrights were still building bicycles. By the middle of the 1920’s he “had it down to a science” (engineering details to be worked out later, of course). A liberal translation goes like this:

 

    * Build, test and fly winged airplanes powered by rocket engines. [Sound familiar, X PRIZE fans?]

 

    * Bit by bit, fly these faster and higher. [We now call it: “Build a little; test a little.”]

 

    * Drop the wings and create true rockets with reaction control systems.

 

    * Learn to splashdown from orbit into the cushioning ocean. [Alan Shepard became Tsiolkovsky’s test pilot in 1961.]

 

    * Get up to Mach 25 and orbit the suckers.

 

    * Incrementally extend your mission durations.

 

    * Learn how to grow plants in zero-G to make atmosphere.

 

    * Get your crews comfortable working outside in pressure-suits.

 

    * Put your EVA skills to work making closed-cycle orbiting plant nurseries.

 

    * Build town-sized space stations in various Earth orbits.

 

    * Harness the Sun to heat your habitats, nurture their plants and push your around the Solar System.

 

    * Expand your operation to the Main Belt of asteroids, using their resources to replicate your large habitats. Encourage big, diverse groups of people to live there.

 

    * Populate the rest of the Solar System -- and as much farther out as you can get -- changing planets as needed. [OK, so there’s the “T” word, finally.]

 

    * Now -- as a consequence of the god-like powers you’ve obtained -- work on changing humans to live more personally fulfilling, socially responsible lives.

 

    * Give in to population pressure and expand Humanity’s range to other stars; spreading Earth’s spawn geometrically.

 

    * Leave the Sun behind entirely -- sometime well before it burns out.

 

So now you have it: a sixteen-step program to an infinite future for the seed of Humankind. Note how late in the game terraforming appears. Almost a century ago, Tsiolkovsky’s stunning intuition showed that long before you get to the level of engineering required to transform whole worlds, you already have everything you need to prosper in space without such worlds! And there are very good reasons not to automatically gravitate to planets.

 

Planet Problems

 

Implicit in this notion of planned planetary engineering is that you have to start with something the size of a whole world. But why do that?

 

Students and followers of Gerard K. O’Neill (yes, this author is one such) have conducted thousands of gentle, loving interventions for the past three decades, trying to help our colleagues get past their inborn “planetary chauvinism.”  Just because you evolved on a planet does not necessitate that you continue to live on one. And there are some profoundly good reasons not to do so. Like that big honkin’ “gravity well” that you have to expensively and dangerously blast your way up out of each time you need to go someplace. And the bigger the planet, the worse the penalty.

 

It’s tough to scale your engineering efforts to alter an existing world, making it ecologically dynamic yet stable enough for biology (like Earth’s beneficial disequilibrium). But in building ever-larger individual contained habitats, you may likely learn the environmental and construction technologies to do so. Along the way, you end up creating a whole host of custom-designed mini-worlds in wide a range of shapes, sizes, climates, gravity levels and life-styles associated with these factors.

 

Importantly, a widely distributed, de-centralized society is much more resilient to (likely completely immune from) acts of senseless terrorism -- even if such acts are perpetrated on a planetary scale: say a diverted retrograde comet; a doomsday bio-weapon; choose your own personal nightmare…

 

And after all, planets are not common, not easy to travel to, and not really all that nearby.

 

Enticing as it may be, Mars is still on the order of 100 million miles away.  And it’s a bitch of an environment to work in: dusty, cold, windy, dry... Much closer are the Near Earth Asteroids; easier to get to than the Moon, much richer in materials too.  Planetary geophysicist Dan Durda says it this way: “By the time you pull all the metals, the rich organic molecules, all the useful volatiles like water, the oxides (for re-entry shields) out of the surface of an asteroid, the slag (the garbage) you have left over has about the same composition as the lunar soil.”   And you, or your teleoperated robot, can work your way around most any asteroid with your fingertips. There’s no deep “gravity well” to climb out of.

 

Way to Go

 

Let’s face it: space settlement -- whether upon the surface of a terraformed sphere or within an engineered one  -- is the living embodiment of “disruptive technology.”  If we go (and I say we must) we will change the Solar System and it will change us.

 

Easy for writers, like yours truly, to sit back and poke irony; hard to “put yer nickel down and bet”. So I say this: Go on, inflame your colleagues.  Debate terraforming all you want. Challenge and duel to your heart’s content.  But at the end of the night  -- and particularly the next morning when it comes time to approach the bankers and the venture capitalists -- let’s do what works.

 

And what works is what takes the least work: Asteroid/comet resources in near Earth orbits. The use of solar energy and electro-tether technology -- and a little bit of nuclear power -- to launch ourselves into a Hydrogen/Oxygen economy, which then would drive higher-order materials processing. And Humanity would get lots and lots of cheap, free-floating, scalable, designer settlements in interesting, useful orbits. Argue about modifying and colonizing whatever mud-balls you want as soon as the technologies truly become available.

 

But if you want to widely populate space soon, do this first. The way Tsiolkovsky, O’Neill and, perhaps, God (or at least the physics of the Universe) intended.

 

Dave Brody has been a Life Member of the National Space Society since 1982. He is currently IMAGINOVA’s Executive Producer and Director of Media; the views expressed herein are entirely his own.

[Nemesis]

It seems someone is already building a planet nearby.

Planet Construction Site Spotted

A vast collection of space pebbles surrounding a relatively nearby star is a planetary construction zone, astronomers said today.

The star, TW Hydrae, is young and ripe for developing new worlds.

New observations reveal a swath of pebble-sized material extending at least a billion miles from the star. It's just the sort of stuff theory says is needed for making comets, asteroids and eventually planets around a young star

[Stormbringer]

Fascinating. I hope it has enough radioactive rocks to build and sustain a molten core.

[Nemesis]

Link to full story

Violent jet detected spewing from brown dwarf

    * 13:06 24 June 2005
    * NewScientist.com news service
    * Maggie McKee

A jet of matter has been detected spewing from a brown dwarf for the first time, mimicking a process seen in young stars. The observation suggests brown dwarfs form like stars - and even hints that jets might once have gushed from planets such as Jupiter and Saturn.

Brown dwarfs occupy the middle ground between planets and stars, weighing between 13 and 75 times the mass of Jupiter. Often called "failed stars", they are not massive enough to burn hydrogen in their cores. But astronomers are divided over what stunts their growth

Apply this to Jovian and sub Jovian planets and you may be giving justification of Velikovsky's "theories".

[Stormbringer]

one thing he did was explain how that planet got it's odd orbit and inclination. as far as I know no one else has even attempted it. I have read his books of course. don't know what to make of it. it certainly is out there though.

[Stormbringer]

planetary scale engineering seriously proposed:   http://www.popsci.com/popsci/aviation/article/0,20967,1075786,00.html

How Earth-Scale Engineering Can Save the Planet
Maybe we can have our fossil fuels and burn ’em too. These scientists have come up with a plan to end global warming. One idea: A 600,000-square-mile space mirror

By Michael Behar | August 2005

 
 
 
 
 
 
 

 
Related Articles: 
How Earth-Scale Engineering Can Save the Planet
Engineered Earthquakes
From The Editor


 
David Keith never expected to get a summons from the White House. But in September 2001, officials with the President’s Climate Change Technology Program invited him and more than two dozen other scientists to participate in a roundtable discussion called “Response Options to Rapid or Severe Climate Change.” While administration officials were insisting in public that there was no firm proof that the planet was warming, they were quietly exploring potential ways to turn down the heat.
Most of the world’s industrialized nations had already vowed to combat global warming by reining in their emissions of carbon dioxide, the chief “greenhouse gas” blamed for trapping heat in Earth’s atmosphere. But in March 2001 President George W. Bush had withdrawn U.S. support for the Kyoto Protocol, the international treaty mandating limits on CO2 emissions, and asked his administration to begin studying other options.

Keith, a physicist and economist in the chemical and petroleum engineering department at the University of Calgary, had for more than a decade been investigating strategies to curtail global warming. He and the other scientists at the meeting—including physicists from Lawrence Livermore National Laboratory who had spent a chunk of their careers designing nuclear weapons—had come up with some ideas for “geoengineering” Earth’s climate. What they proposed was tinkering on a global scale. “We already are inadvertently changing the climate, so why not advertently try to counterbalance it?” asks retired Lawrence Livermore physicist Michael MacCracken, a former senior scientist at the U.S. Global Change Research Program who helped organize the meeting.

“If they had broadcast that meeting live to people in Europe, there would have been riots,” Keith says. “Here were the bomb guys from Livermore talking about stuff that strikes most greens as being completely wrong and off-the-wall.” But today, a growing number of physicists, oceanographers and climatologists around the world are seriously considering technologies for the deliberate manipulation of Earth’s climate. Some advocate planetary air-conditioning devices such as orbiting space mirrors that deflect sunlight away from Earth, or ships that intensify cloud cover to block the sun’s rays. Others are suggesting that we capture carbon dioxide—from the air, from cars and power plants—and stash it underground or react it with chemicals that turn it to stone.

[continued]

[Stormbringer]

Carbon dioxide wasn’t always public enemy number one. For the past 400,000 years, the concentration of CO2 in the atmosphere has fluctuated between about 180 and 280 ppm (parts per million, the number of CO2 molecules per million molecules of air). But in the late 1800s, when humans set about burning fossil fuels in earnest, atmospheric CO2 began to increase with alarming speed—from about 280 ppm to the current level of almost 380 ppm, in a scant 100 years. Experts predict that CO2 could climb as high as 500 ppm by 2050 and possibly twice that by the end of the century. As CO2 levels continue to rise, the planet will get hotter. “The question now,” says Ken Caldeira, an atmospheric scientist at Lawrence Livermore and one of the world’s leading authorities on climate change, “is what can we actually do about it?” Here are some of the geoengineering schemes under consideration.

1. Store CO2 Underground
Feasibility: 10
Cost: $$
RISK: 4
In the southeastern corner of Saskatchewan, just outside the town of Weyburn—the “Opportunity City”—a steel pipeline descends 4,000 feet below the prairie at the edge of a 70-square-mile oil field. Into this subterranean cavern, petroleum engineers are pumping 5,000 tons of pressurized, liquefied carbon dioxide every day. The aim is twofold: Use high-pressure CO2 to drive oil from the porous rock in the reservoir to the surface, and trap the carbon dioxide underground.
Welcome to the world’s largest carbon-sequestering operation. Dubbed the Weyburn Project, it began in July 2000 as a partnership between EnCana, a Canadian oil and gas company, and Canada’s Petroleum Technology Research Centre. With $13 million in funding from more than a dozen sponsors, including the U.S. Department of Energy, engineers have already socked away six million tons of carbon dioxide, roughly the amount produced by burning half a billion gallons of gasoline.

The Timeline
Unlike other geoengineering schemes, this one is already happening, with more than half a dozen major projects under way. The problem, says Howard Herzog, a principal research engineer at MIT’s Laboratory for Energy and the Environment, is that concentrated CO2 is in short supply. There’s too much of the gas floating around in the air, but actually capturing, compressing, and transporting it costs money. In the U.S. and most other nations, there are no laws requiring fossil-fuel-burning power plants—the primary source of CO2 emissions—to capture a single molecule of the gas.

The Promise
By 2033, the Weyburn Project will store 25 million tons of carbon dioxide. “That’s like taking 6.8 million cars off the road for one year,” says project manager Mike Monea, “and this is just a pilot test in a small oil reservoir.” Saline aquifers, giant pools of saltwater that have been trapped underground for millions of years, could hold even more CO2. Humans dump about 28 gigatons of CO2 into the atmosphere every year. Geologists estimate that underground reservoirs and saline aquifers could store as much as 200,000 gigatons.

The Perils
Before CO2 is injected into the ground, it’s compressed into what’s called a supercritical state—it’s extremely dense and viscous, and behaves more like a liquid than a gas. In this form, CO2 should remain trapped underground for thousands of years, if not indefinitely. The danger is if engineers accidentally “depressurize” an aquifer while probing for oil or natural gas. There’s also a risk that carbon dioxide could escape slowly through natural fissures in subterranean rock and pool up in basements or cellars. “If you walked down into a basement [full of CO2],” Keith says, “you wouldn’t smell it or see it, but it would kill you.”

2. Filter CO2 from the air
Feasibility: 4
Cost: $$$
RISK: 4
Klaus Lackner is accustomed to skeptics. They’ve doubted him since he first presented his idea for extracting carbon dioxide from ambient air in March 1999, at an international symposium on coal and fuel technology. “The reaction from everyone there was utter disbelief,” recalls Lackner, a physicist with the Earth Engineering Center at Columbia University.

He called for the construction of giant filters that would act like flypaper, trapping CO2 molecules as they drifted past in the wind. Sodium hydroxide or calcium hydroxide—chemicals that bind with carbon dioxide—would be pumped through the porous filters much the way antifreeze is circulated through a car’s radiator. A secondary process would strip the CO2 from the binding chemical. The chemical would recirculate through the filter, while the CO2 would be set aside for disposal.

The Timeline
Lackner is collaborating with engineer Allen Wright, who founded Global Research Technologies in Tucson, Arizona. Wright is developing a wind-scrubber prototype but remains tight-lipped about the project. He estimates that a completed system is at least two years away.

The Promise
Wind scrubbers can be placed wherever it’s convenient to capture carbon dioxide, so there’s no need to transport it. Lackner calculates that a wind scrubber designed to retain 25 tons of CO2 per year—the average amount each American adds to the atmosphere annually—would require a device about the size of a large plasma-screen television. A single industrial-size wind scrubber about 200 feet high and 165 feet wide would snag about 90,000 tons of CO2 a year.

The Perils
Some experts are dubious about the ease of separating carbon dioxide from the binding chemical, a process that in itself would require energy from fossil fuels. “CO2 is so dilute in the air that to try to scrub from it, you have to pay too much for energy use,” Herzog says. And to capture all the carbon dioxide being added to the atmosphere by humans, you’d need to blanket an area at least the size of Arizona with scrubber towers.

[continue]

[Stormbringer]

3.Fertilize the ocean
Feasibility: 10
Cost: $
RISK: 9
On January 5, 2002, Revelle, a research vessel operated by the Scripps Institution of Oceanography, left New Zealand for the Southern Ocean—a belt of frigid, stormy seas that separates Antarctica from the rest of the world. There the scientists dumped almost 6,000 pounds of iron powder overboard and unleashed an armada of instruments to gauge the results.
The intent was to test a hypothesis put forth by oceanographer John Martin. At a lecture more than a decade ago, Martin declared: “Give me a half-tanker of iron, and I will give you an ice age.” He was alluding to the fact that the Southern Ocean is packed with minerals and nutrients but strangely devoid of sea life. Martin had concluded that the ocean was anemic—containing very little iron, an essential nutrient for plankton growth. Adding iron, Martin believed, would cool the planet by triggering blooms of CO2-consuming plankton.

Oceanographer Kenneth Coale, who directs the Moss Landing Marine Laboratories near Monterey, California, was a chief scientist on the Southern Ocean cruise. He says the project was a success, proving that relatively small quantities of iron could spawn colossal blooms of plankton.

The Timeline
Scientists are wary, saying that too little is known about the deep-ocean environment to endorse further large-scale experiments. In October, Coale and other scientists will gather in New Zealand for a weeklong meeting sponsored by the National Science Foundation, New Zealand’s National Institute for Water and Atmosphere, and the International Geosphere-Biosphere Programme to decide how to proceed.

The Promise
Iron fertilization is by far the cheapest and easiest way to mitigate carbon dioxide. Coale estimates that just one pound of iron could conceivably hatch enough plankton to sequester 100,000 pounds of CO2. “Even if the process is only 1 percent efficient, you just sequestered half a ton of carbon for a dime.”

The Perils
“What is still a mystery,” Coale says, “is the ripple effect on the rest of the ocean and the food chain.” One fear is that huge plankton blooms, in addition to gorging on CO2, will devour other nutrients. Deep currents carry nutrient-rich water from the Southern Ocean northward to regions where fish rely on the nutrients to survive. Says Coale, “A fertilization event to take care of atmospheric CO2 could have the unintended consequence of turning the oceans sterile. Oops.”

4. Turn CO2 to Stone
Feasibility: 7
Cost: $$
RISK: 3
The Grand Canyon is one of the largest carbon dioxide repositories on Earth. Hundreds of millions of years ago, a vast sea covered the land there. The water, rich in carbon dioxide, slowly reacted with other chemicals to create calcium carbonate, or limestone—the pinkish bands striping the canyon walls today.

Nature’s method for turning CO2 to stone is achingly slow, but researchers at the Goldwater Materials Science Laboratory at Arizona State University are working on a way to speed up the process. Michael McKelvy and Andrew Chizmeshya use serpentine or olivine, widely available and inexpensive minerals, as feedstock to fuel a chemical reaction that transforms CO2 into magnesium carbonate, a cousin of limestone. To initiate the reaction—known as “mineral carbonation”—the CO2 is compressed, heated, and mixed with feedstock and a catalyst, such as sodium bicarbonate (baking soda).

The Timeline
Scaling up the process to handle millions of tons of CO2 would require huge quantities of serpentine or olivine. A single mineral-carbonation plant would carve out a mountain, but, McKelvy says, “You could carbonate [the CO2] and put it right back where the feedstock came from.”

The Promise
Mineral carbonation is simply an accelerated version of a benign natural process. The limestone in the Grand Canyon is 500 feet thick, McKelvy says, “and it has been sitting there not bothering anybody for millennia.”

The Perils
It costs roughly $70 to eliminate one ton of CO2, a price that McKelvy says is too high. Also, the feedstock and CO2 must be heated to high temperatures. “You wind up having to burn fossil fuels in order to provide the energy to activate the mineral to put away the CO2,” he says.

[continue]

[Stormbringer]

5. Enhance Clouds to Reflect Sunlight
Feasibility: 6
Cost: $$
RISK: 7
Some proposed solutions to global warming don’t involve capturing carbon dioxide. Instead they focus on turning down the heat by deflecting or filtering incoming sunlight.
On any given day, marine stratocumulus clouds blanket about one third of the world’s oceans, mostly around the tropics. Clouds form when water vapor clings to dust or other particles, creating droplets. Seeding clouds with tiny salt particles would enable more droplets to form—making the clouds whiter and therefore more reflective. According to physicist John Latham, a senior research associate at the National Center for Atmospheric Research in Boulder, Colorado, boosting reflectivity, or albedo, in just 3 percent of marine stratocumulus clouds would reflect enough sunlight to curb global warming. “It would be like a mirror for incoming solar radiation,” Latham explains.

Latham is collaborating with Stephen Salter, an emeritus professor of engineering design at the University of Edinburgh, who is making sketches for GPS-steered wind- powered boats that would cruise the tropical latitudes, churning up salt spray. “I am planning a flotilla of unmanned yachts sailing backward and forward across the wind,” Salter says. “They would drag propellers through the water to generate electricity, which we’d use to make the spray.”

Salter wants to outfit each boat with four 60-foot-tall Flettner rotors, which look like smokestacks but act like sails. An electric motor starts each rotor spinning, which, along with the wind, creates a pressure differential (less pressure in front of the rotor, more in back), generating forward thrust. From the top of the rotor, an impeller would blast a fine saltwater mist into the air.

Until the concept is tested, Salter isn’t sure exactly how many ships would be needed to mitigate global warming. “Maybe between 5,000 and 30,000,” he says. That may sound like a lot, but Salter notes that for World War II, the U.S. built nearly 100,000 aircraft in 1944 alone.

The Timeline
Latham initially raised the notion in a 1990 paper. “The article went down like a lead balloon,” he says. But early last year in England, at a geoengineering conference hosted by MIT and the Tyndall Centre for Climate Change Research, he presented the concept again. “The consensus was that a number of ideas originally thought to be outlandish were deemed sufficiently plausible to be supported further. Our work fell into that category.” Latham needs a few million dollars to test his idea. “On the scale of the damage that will be caused by global warming, that is utterly peanuts.”

The Promise
What’s nice about this idea is that it can easily be fine-tuned. “If we tried it and there was some deleterious effect, we could switch it off, and within four or five days all evidence would have disappeared,” Latham says.

The Perils
One worry is that although the tiny salt particles released by evaporating sea mist are perfect for marine stratocumulus-cloud formation, they are too small to create rain clouds. “You might make it harder for rain to form,” Salter says. “Therefore, you would not want to do this upwind of a place where there is a bad drought.”

6. Deflect Sunlight With A Mirror
Feasibility: 1
Cost: $$$$
RISK: 5
One of the most ambitious schemes is a giant space “mirror” positioned between the Earth and sun to intercept sunlight. To build the mirror, physicist Lowell Wood, a senior staff scientist at Lawrence Livermore, proposes using a mesh of aluminum threads that are only a millionth of an inch in diameter and a thousandth of an inch apart. “It would be like a window screen made of exceedingly fine metal wire,” he explains. The screen wouldn’t actually block the light but would simply filter it so that some of the incoming infrared radiation wouldn’t reach Earth’s atmosphere.

The Timeline
Wood, who has been researching the mirror idea for more than a decade, says it should be considered only as a safety net if all other means of reversing global warming “fail or fall grossly short over the next few decades.”

The Promise
Once in place, the mirror would cost almost nothing to operate. From Earth, it would look like a tiny black spot on the sun. “People really wouldn’t see it,” says Michael MacCracken. And plant photosynthesis isn’t expected to be affected by the slight reduction in sunlight.

The Perils
Wood calculates that deflecting 1 percent of incoming solar radiation would stabilize the climate, but doing so would require a mirror spanning roughly 600,000 square miles—or several smaller ones. Putting something that size in orbit would be a massive challenge, not to mention exorbitantly expensive.

[end]

[Stormbringer]

OK remember one objection to my premise of building a planet from scratch was the amount of available mass free to do so in the solar system. well every week we get announcements indidcating the sparce mass beleif of scientists is wrong now there is this one:

Gemini Samples Spectrum Of 2003 UB313: Pluto-Like Surface

Figure 2: 2003 UB313 spectrum (red, obtained at Gemini Observatory by Trujillo, Brown and Rabinowitz) and Pluto (black, from Rudy et al. 2003). The "dips" characteristic of methane ice are indicated by red arrows and are present in both 2003 UB313 and Pluto.
Washington DC (SPX) Jul 31, 2005
The Gemini Observatory has obtained a preliminary spectrum of 2003 UB313, the lastest so-called "10th planet". These observations were obtained on January 25, 2005 by Chad Trujillo, a Gemini staff member who is also on the discovery team for 2003 UB313, the existence of which was formally announced by the Minor Planet Center in Cambridge, MA on July 29, 2005.
The discovery team (Mike Brown of Caltech, Chad Trujillo of Gemini and David Rabinowitz of Yale) are still uncertain of the exact size of the body, but report that it must be Pluto-sized or larger. The body is the most distant solar system body known to orbit the sun at 97 AU from the sun, over 3 times farther away than planet Pluto.

The "planet" was originally discovered in late December 2004 with data collected from the Samuel Oschin 1.2 meter telescope at Palomar Mountain, CA.

To better characterize the surface of the object the team obtained spectra with NIRI (the near-infrared spectrograph) on the much larger 8 meter Gemini North telescope on Mauna Kea, Hawaii.

The NIRI spectra shows strong signatures of methane ice, remarkably similar to the spectrum of Pluto, which is also dominated by methane ice in near-infrared observations.

Figure 2 shows the spectra of Pluto and 2003 UB313, with arrows marking the "dips" that correspond to methane features. The same features are readily apparent in both the Pluto and the 2003 UB313 spectra.

Trujillo states, "We still do not know much about this object, however, it is clear that it is very similar to Pluto in both size and composition, at least upon first glance."

The presence of methane ice is unusual in that it indicates a primitive surface that has not likely been heated significantly since the solar system formed 4.5 billion years ago.

"If 2003 UB313 ever got close to the sun, all the methane ice would have boiled off immediately," Trujillo continued.

"To date, no one has seen methane on any other Kuiper Belt Object, only on Pluto and Neptune's moon Triton." The distant Kuiper Belt is a collection of bodies orbiting the sun beyond Neptune, and is likely the parent population to the comets.

The team have also obtained spectra of the smaller mini-planet 2003 EL61, which was reported on July 28, 2005 by two independent teams: one from the Sierra Nevada Observatory in Spain and the Brown, Trujillo and Rabinowitz team. This object is smaller than Pluto, but shows strong water-ice features, similar to what is seen on the surface of Pluto's moon Charon.

Results will be reported in detail at the 37th annual meeting of the Division for Planetary Sciences of the American Astronomical Society in September 2005 at the University of Cambridge, UK.

[Stormbringer]

lots of info on kuiper objects in this article from space daily.com: 

Mysterious Deep-Space Object Raises Questions On Origin Of Solar System

An edge-on-view of the solar system to show the tilt of Buffy's orbit. See larger image. Credits: The Canada France Ecliptic Plane Survey.
Paris (AFP) Dec 13, 2005
Astronomers working in Canada, France and the United States said Tuesday they had found a small deep-space object, nicknamed Buffy, that challenges mainstream theories about the evolution of the Solar System.
The rock lies in the Kuiper Belt, the name for the flock of objects beyond Neptune's orbit that are believed to be leftover rubble from the Solar System's building phase and are the source for many comets, the Canada-France Ecliptic Plane Survey (CFEPS) said.

Measuring between 500 and 1,000 kilometers (300 to 600 miles) across and taking about 440 years to make just one circuit of the Sun, Buffy is remarkable not for its size -- around half a dozen identified Kuiper Belt objects are bigger -- but for its location and orbital tilt.
"This new object challenges current theories about the history of the early Solar System," CFEPS said in a press release.

"(...) This new discovery is exciting because it causes us to rethink our understanding about how the Kuiper Belt formed." Buffy has an almost perfect circular orbit and encircles the Sun at an extreme tilt, at 47 degrees to the orbital plane of the planets as they swing around the Sun.

But it lies in a curious outer region of the Kuiper Belt, on the dark, bone-freezing fringes of the Solar System.

The theory is that, billions of years ago, this remote community of rocks, the so-called "extended scattered disk" of the Kuiper Belt, got their extremely eccentric orbits because of a passing star.

The star's gravitational pull was enough to give the objects a tug, pulling them out of a circular orbit but not enough to coax them away from enslavement to the Sun.

But Buffy is the odd one out -- its almost-perfect orbit and tilt circular puts a dent in the "star" theory.

One possibility, the discoverers say, is that, in the infant days of the Solar System, the nascent Neptune lay much closer to the Sun.

It eventually migrated outwards, causing at least some members of the Belt's "extended scattered disk" to develop more circular and tilted orbits, they speculate.

Buffy is the temporary name given by the team for the object, whose official designation by the Paris-based International Astronomical Union (IAU) is 2004 XR 190.

Its orbit is in a relatively narrow range of between 52 and and 62 astronomical units (AU) from the Sun (an AU is a standard measurement, being that of the distance between the Earth and the Sun, of approximately 150 million kilometers, or 93 million miles).

By comparison, another "extended scattered disk" member called Sedna swings out to as far as 900 AU before coming as close to the Sun as 76 AU.

The Kuiper Belt was first recognised in 1992.

Most of its objects lie in a region that extends from 30 to 50 AU where there are "at least" 70,000 rocks with a diameter of 100 kms (60 miles) or more, according to David Jewitt, a specialist at the University of Hawaii.
Buffy was first noted by Lynne Allen of the University of British Columbia, Canada, in December last year as she pored over data from powerful computers that sift through telescopic images in search of new celestial sightings.

Because Kuiper Belt objects take so long to go around the Sun, it takes between one and two years of additional observations to calculate their orbits precisely.

Further measurements are needed over the next three months for a fine-tuning of Buffy's orbit.

related report


Discovery of a large Kuiper Belt object with an unusual orbit

A team of astronomers working in Canada, France and the United States have discovered an unusual small body orbiting the Sun beyond Neptune, in the region astronomers call the Kuiper belt. This new object is twice as far from the Sun as Neptune and is roughly half the size of Pluto. The body, temporarily code-named "Buffy", has a highly unusual orbit which is difficult to explain using previous theories of the formation of the outer Solar System.

Currently 58 astronomical units from the Sun (1 astronomical unit, or AU, is the distance between the Earth and the Sun), the new object never approaches closer than 50 AU, because its orbit is close to circular.

Almost all Kuiper belt objects discovered beyond Neptune are between 30 AU and 50 AU away. Beyond 50 AU, the main Kuiper belt appears to end, and what few objects have been discovered beyond this distance have all been on very high eccentricity (non-circular) orbits.

Most of these high-eccentricity orbits are the result of Neptune "flinging" the object outward by a gravitational slingshot. However, because this new object does not approach closer than 50 AU, a different theory is needed to explain its orbit. Complicating the problem, the object's orbit also has an extreme tilt, being inclined (tilted) at 47 degrees to the rest of the Solar System.


Source: Agence France-Presse

[Stormbringer]

[SNIP]

Measuring between 500 and 1,000 kilometers (300 to 600 miles) across and taking about 440 years to make just one circuit of the Sun, Buffy is remarkable not for its size -- around half a dozen identified Kuiper Belt objects are bigger -- but for its location and orbital tilt.

[SNIP]

Most of its objects lie in a region that extends from 30 to 50 AU where there are "at least" 70,000 rocks with a diameter of 100 kms (60 miles) or more, according to David Jewitt, a specialist at the University of Hawaii.

[SNIP]

Thats a lot of mass! and that does not include the Oort cloud proper or the asteroid belts. so is this enough mass to fire up the Magrathea planet factory?

[prometheus]

What if we send a fleet of self replicating robotic tugs, solar collector oven satellites and ancilliary equipment to the asteroid belt.

We aren't even confident of our ability to move an asteroid on a collision course with Earth yet, let alone our ability to transport them around the solar system...  And out in space, where are the raw materials for self replication going to come from?

[prometheus]

Not necessarilly. a great deal of venus's heat problem is due to runaway greenhouse conditions due to compounds like sulfuric acid in her atmosphere. with the removal of those compounds and the addition of compounds or gases that do not trap heat well the temperature could be lowered to earth norms. just as mars temperatures could reach earth norms with the proper atmosphere. the highest recorded summer temperature on mars is 80 degrees F. which is quite acceptable to humans. Venus could be further cooled with large scale reflectors in orbit around her. However moving her would be a good idea and it would not effect the earth in any way. right now we don't have the means to move a whole planet but in the future we might. A russian scientist has had some success with antigravity research. he became famous for reducing the apparent weight of masses with superconducting disk magnets. Since then he has apparently managed to create a gravity and antigravity beam and his work has been taken up by thousands of amateur enthusiasts. 

Ground Control to Major Tom?  Moving Venus? 

We haven't even moved ourselves beyond LEO in the last thirty three years...  What we want to be doing is setting up ambitious space prjects with realistic goals...

[Stormbringer]

What if we send a fleet of self replicating robotic tugs, solar collector oven satellites and ancilliary equipment to the asteroid belt.

We aren't even confident of our ability to move an asteroid on a collision course with Earth yet, let alone our ability to transport them around the solar system...  And out in space, where are the raw materials for self replication going to come from?

The asteroids. these self replicating probes will be about the size of a salt box. along with  swarms of smaller 'bots down to molecular machine size. when their job is done they will deorbit on the planet adding a infinitesimal fraction of mass to it.

[Stormbringer]

Not necessarilly. a great deal of venus's heat problem is due to runaway greenhouse conditions due to compounds like sulfuric acid in her atmosphere. with the removal of those compounds and the addition of compounds or gases that do not trap heat well the temperature could be lowered to earth norms. just as mars temperatures could reach earth norms with the proper atmosphere. the highest recorded summer temperature on mars is 80 degrees F. which is quite acceptable to humans. Venus could be further cooled with large scale reflectors in orbit around her. However moving her would be a good idea and it would not effect the earth in any way. right now we don't have the means to move a whole planet but in the future we might. A russian scientist has had some success with antigravity research. he became famous for reducing the apparent weight of masses with superconducting disk magnets. Since then he has apparently managed to create a gravity and antigravity beam and his work has been taken up by thousands of amateur enthusiasts. 

Ground Control to Major Tom?  Moving Venus? 

We haven't even moved ourselves beyond LEO in the last thirty three years...  What we want to be doing is setting up ambitious space prjects with realistic goals...

you post this as if the main thrust of my post was the idea that we were going to have to move venus in the first place when in fact the gist of what i said concerning the notion was that at some time in the future such a feat might not seem as impossible to us as it does today. you see no problem in portraying my post as if i announced my intent to hook a peterbilt up to her and drop the clutch immediately and then attacking that distorted portrayal?

[Nemesis]

Link to full article

PASADENA, Calif. (AP) – Astronomers have spotted a swirling debris cloud around a sun-like star where terrestrial planets similar to Earth may be forming in a process that could shed light on the birth of the solar system.

Looks like Stormbringer is practicing.

[prometheus]

Not necessarilly. a great deal of venus's heat problem is due to runaway greenhouse conditions due to compounds like sulfuric acid in her atmosphere. with the removal of those compounds and the addition of compounds or gases that do not trap heat well the temperature could be lowered to earth norms. just as mars temperatures could reach earth norms with the proper atmosphere. the highest recorded summer temperature on mars is 80 degrees F. which is quite acceptable to humans. Venus could be further cooled with large scale reflectors in orbit around her. However moving her would be a good idea and it would not effect the earth in any way. right now we don't have the means to move a whole planet but in the future we might. A russian scientist has had some success with antigravity research. he became famous for reducing the apparent weight of masses with superconducting disk magnets. Since then he has apparently managed to create a gravity and antigravity beam and his work has been taken up by thousands of amateur enthusiasts. 

Ground Control to Major Tom?  Moving Venus? 

We haven't even moved ourselves beyond LEO in the last thirty three years...  What we want to be doing is setting up ambitious space prjects with realistic goals...

you post this as if the main thrust of my post was the idea that we were going to have to move venus in the first place when in fact the gist of what i said concerning the notion was that at some time in the future such a feat might not seem as impossible to us as it does today. you see no problem in portraying my post as if i announced my intent to hook a peterbilt up to her and drop the clutch immediately and then attacking that distorted portrayal?

No, what I was meaning was that when all the space cadets who engage in enlightened prediction come spiralling back down to Earth, I think one has to accept that moving planets is, and always will be, a little out of our jurisdiction.  Force = mass x accelaration.  Middle School maths.  the force you would require to move an object the size of Venus is beyond imagination.  Hell, we can't even be confident of deflecting an asteroid several orders of magnitude smaller and lighter than Venus from hitting us and wiping us out.  This kind of speculation about moving planets is not worth engaging in...

[prometheus]

What if we send a fleet of self replicating robotic tugs, solar collector oven satellites and ancilliary equipment to the asteroid belt.

We aren't even confident of our ability to move an asteroid on a collision course with Earth yet, let alone our ability to transport them around the solar system...  And out in space, where are the raw materials for self replication going to come from?

The asteroids. these self replicating probes will be about the size of a salt box. along with  swarms of smaller 'bots down to molecular machine size. when their job is done they will deorbit on the planet adding a infinitesimal fraction of mass to it.

That doesn't really answer my question...  We replicate by drawing biomatter from the ecosystem we exist in...  How are these probes going to accomplish the same feat when they will have to exist in a vacuum and operate on lumps of metal, ice and rock?

[Stormbringer]

What if we send a fleet of self replicating robotic tugs, solar collector oven satellites and ancilliary equipment to the asteroid belt.

We aren't even confident of our ability to move an asteroid on a collision course with Earth yet, let alone our ability to transport them around the solar system...  And out in space, where are the raw materials for self replication going to come from?

The asteroids. these self replicating probes will be about the size of a salt box. along with  swarms of smaller 'bots down to molecular machine size. when their job is done they will deorbit on the planet adding a infinitesimal fraction of mass to it.

That doesn't really answer my question...  We replicate by drawing biomatter from the ecosystem we exist in...  How are these probes going to accomplish the same feat when they will have to exist in a vacuum and operate on lumps of metal, ice and rock?

At the nano level atoms could be seperated mechanically atom by atom or catalytically or using electrostatic or magnetic or even EM forces.  Most of this has been acomplished at nano scale in the laboratory. the larger probes would  break up asteroid material if necessary. the nano scales ones would work on dust sized particles. Also the larger ones would act as seperators, forges, and fabricators. once they have reproduced a number of times they would drop the reproductive mission and assume the planetary construction mission. there are a number of ways that could be worked out to divide the reproductive and constructive missions to optimize the alogrithmic progression. it could even be more adaptive so that constructors could return to the reproductive role if necessary for some reason.       

[prometheus]

What if we send a fleet of self replicating robotic tugs, solar collector oven satellites and ancilliary equipment to the asteroid belt.

We aren't even confident of our ability to move an asteroid on a collision course with Earth yet, let alone our ability to transport them around the solar system...  And out in space, where are the raw materials for self replication going to come from?

The asteroids. these self replicating probes will be about the size of a salt box. along with  swarms of smaller 'bots down to molecular machine size. when their job is done they will deorbit on the planet adding a infinitesimal fraction of mass to it.

That doesn't really answer my question...  We replicate by drawing biomatter from the ecosystem we exist in...  How are these probes going to accomplish the same feat when they will have to exist in a vacuum and operate on lumps of metal, ice and rock?

At the nano level atoms could be seperated mechanically atom by atom or catalytically or using electrostatic or magnetic or even EM forces.  Most of this has been acomplished at nano scale in the laboratory. the larger probes would  break up asteroid material if necessary. the nano scales ones would work on dust sized particles. Also the larger ones would act as seperators, forges, and fabricators. once they have reproduced a number of times they would drop the reproductive mission and assume the planetary construction mission. there are a number of ways that could be worked out to divide the reproductive and constructive missions to optimize the alogrithmic progression. it could even be more adaptive so that constructors could return to the reproductive role if necessary for some reason.       

How are they going to produce rubber insulation, copper cables, pnp semiconductors, plasitc polymers etc from the raw materials on an asteroid?

[Stormbringer]

Molecule by molecule. this type of synthesis has been demonstrated in principle by scientists and engineers working on micro assembly techniques using ion probe microscopes modifed forthe task. while it might sound slow, actually it would not be; because the initial swarm (millions or billions of nano scale machinesmass produced by automated plasma vapor deposition or IC die machines) and thousands of the larger processing/factory/forge bots will be made on earth and transported out to thier job site.

[prometheus]

Molecule by molecule. this type of synthesis has been demonstrated in principle by scientists and engineers working on micro assembly techniques using ion probe microscopes modifed forthe task. while it might sound slow, actually it would not be; because the initial swarm (millions or billions of nano scale machinesmass produced by automated plasma vapor deposition or IC die machines) and thousands of the larger processing/factory/forge bots will be made on earth and transported out to thier job site.

Sounds unlikely in the extreme...  We can't even explain how it happened in Earth based life, let alone replicate the process.  I wonder why human's have so much trouble accepting the fact that technology has limitations?

[Stormbringer]

But it is not life. it is a manufacuring technique that has some characteristics  in common with living organisms.

[prometheus]

But it is not life. it is a manufacuring technique that has some characteristics  in common with living organisms.

Biologists are in agreement that if something can satisfy the following conditions

   1. Growth, development, maturity
   2. Metabolism, consuming, transforming and storing energy/mass; growing by absorbing and reorganizing mass; excreting waste
   3. Motion, either moving itself, or having internal motion
   4. Reproduction, the ability to create entities that are similar to, yet separate from, itself or consisting solely of entities that exhibit the quality of reproduction.
   5. Response to stimuli - the ability to measure properties of its surrounding environment, and act upon certain conditions. This property is also called homeostasis.

that by any sensible definition it is alive.  Your probes will have to satisfy all of these conditions...

[Stormbringer]

Right off the bat the probes will violate condition one.

[prometheus]

Right off the bat the probes will violate condition one.

Don't be absurd...  Do you think they are going to instantly appear fully formed in a puff of smoke if they are built molecule by molecule, or if they are "built" at all for that matter?  Don't think of growth, maturity, developement in a 12 step program way, think of it the way a biologist sees it and it makes sense...

The ability to self regulate damage is considered growth to a biologist.  If you cut yourself, do you not heal with no conscious effort on your part?

These machines will have to grow and develope until they reach a state of completion, which is maturity...

[Stormbringer]

But that growth is not directed by an  genetic code integral to the "growing" object nor is the object itself doing the "metabolizing."  if you say that a manufactured nanobot is growing in a biological sense then you must say any manufactured object meets the living criteria.

[prometheus]

But that growth is not directed by an  genetic code integral to the "growing" object nor is the object itself doing the "metabolizing."  if you say that a manufactured nanobot is growing in a biological sense then you must say any manufactured object meets the living criteria.

No biologist has ever stated that all life in the Universe has to be DNA based...  That would be an absurd statement to make given that there is no data to confirm or deny it.

The probe, if it is converting and distributing energy in an organized, meaningful and self regulating way, is metabloising, and if the probe is capable of building on or repairing itself according to a pre determined plan, as a human does, it is growing.  Whether the code it is following is genetic or binary makes no fundamental difference...

[Stormbringer]

Not really. there must be an integral programming which includes the urge to reproduce and which governs the building process and repair process internally. these nanoprobes  were not discussed WRT self repair. they do not direct their own creation once stasrted. that process is completely controlled externally by nanobots that are already complete. as the components accrue those components do not control the process. there is no "cellular" life processes. 

[prometheus]

Not really. there must be an integral programming which includes the urge to reproduce and which governs the building process and repair process internally. these nanoprobes  were not discussed WRT self repair. they do not direct their own creation once stasrted. that process is completely controlled externally by nanobots that are already complete. as the components accrue those components do not control the process. there is no "cellular" life processes. 

How can they reproduce if they don't have an inbuilt urge to do so?

[Stormbringer]

They do. but their reproductive means are external. they have no generative organs. they also do not divide in the manner of cells. the new bot to be does not self organize. the partially assembled device has no life drives. leave a partly assembled bot alone and it will not go on building itself. It cannot do it.

Conversely;  when gametes meet given a proper environment the resulting organism divides, metabolizes, comunicates chemically, follows it's own integral instructions and does display survival and other living behaviors. a fetus is programmed to live and will struggle and adapt in order to facilitate that.

[prometheus]

They do. but their reproductive means are external. they have no generative organs. they also do not divide in the manner of cells. the new bot to be does not self organize. the partially assembled device has no life drives. leave a partly assembled bot alone and it will not go on building itself. It cannot do it.

Conversely;  when gametes meet given a proper environment the resulting organism divides, metabolizes, comunicates chemically, follows it's own integral instructions and does display survival and other living behaviors. a fetus is programmed to live and will struggle and adapt in order to facilitate that.

True, but we're splitting hairs here...  A gamete has more chance of ending up on your girlfriends chest or flushed down the toilet in a tampon and winding up on the nearest beach than creating a new life form...  A newborn baby would be dead in a matter of days left to it's own devices, so the requisition of external influence does not disqualify something from being alive...

But to get back to what I was on about originally, if we can figure out how environmental variables lead to the creation of self motivating automata (ie ourselves), we stand a much better chance of (no pun intended) reproducing the process...

[Stormbringer]

Self assembling materials have been created in the laboratory. a micron sized device that has it's own motive means has been made and demonstrated. add enough complexity of parts increases the size a bit but these things arre still microscopic. admitedly a device that can follow a program has not yet been done but it is only a matter of time. the devices i envision do not need to be self assembling in the sense above but in the sense that they can build replicas from spare parts. those spare parts either being made by specialized miner forging bots or by earlier versions of themselves if they are generalized enough to handle mining, extracting forging and assembly themselves. each process adds to the size and complexity of each unit. at some point specialization makes more sense. but it seems doable to me.

[prometheus]

Self assembling materials have been created in the laboratory. a micron sized device that has it's own motive means has been made and demonstrated. add enough complexity of parts increases the size a bit but these things arre still microscopic. admitedly a device that can follow a program has not yet been done but it is only a matter of time. the devices i envision do not need to be self assembling in the sense above but in the sense that they can build replicas from spare parts. those spare parts either being made by specialized miner forging bots or by earlier versions of themselves if they are generalized enough to handle mining, extracting forging and assembly themselves. each process adds to the size and complexity of each unit. at some point specialization makes more sense. but it seems doable to me.

Well, who knows...  It's not likely to be in my lifetime, so I guess I'll never find out...

[Stormbringer]

http://space.com/scienceastronomy/060814_tno_found.html

Discovery Hints at a Quadrillion Space Rocks Beyond Neptune

By Sara Goudarzi
Staff Writer
posted: 15 August 2006
06:13 am ET
 


Dozens of rocky bodies that are part of a sea of small rocky fragments never observed before have been spotted in the suburbs of our solar system beyond planet Neptune, thanks to a novel technique.


These newly detected chunks of dust and rock coined Trans-Neptunian Objects (TNO) are smaller than 330 feet (100 meters) across. They are leftovers from the formation of planets.


Scientists had previously detected TNOs larger than 31 miles (50 kilometer) across such as the Kuiper Belt Objects (KBO), a subset of TNOs. They suspected that there may be distant objects beyond Neptune since the 1940's, but it wasn't until 1992 that the first KBO was discovered. 


Since then, they've found so many large objects in the outskirts of the solar system that they had to come up with crazy names, like Plutinos, Centaurs, and Cubewanos, to keep them in order. And although researchers suspected the presence of smaller objects, they didn't have a way to detect the sea of debris.


"The searches for Kuiper Belt Objects usually look for reflected light from the Sun and the small motion relative to fixed background stars," said Asantha Cooray, assistant professor of Physics and Astronomy at the University of California, Irvine.  The amount of reflected light from a small body, however, is so extremely dim that not even the largest telescopes, or much larger telescopes one could imagine building either on Earth or space, could see it.


But scientists didn't look for the reflected light this time. Examining data from NASA's Rossi X-ray Timing Explorer, they monitored the light from a background star, Scorpius X-1, as small objects moved in front of it in what are called occultations. They found obvious dips in the light.


Other than the Sun, Scorpius X-1 is the brightest X-ray source in the sky, said study leader Hsiang-Kuang Chang, Associate Professor of Physics & Institute of Astronomy at the National Tsing Hua University, Taiwan.


"We discussed various possibilities for causing these dips and concluded that occultation by small TNOs are the most likely one," he told SPACE.com in an email interview.


Alltogether, Chang and colleagues identified 58 definite dips. Their findings are detailed in the Aug. 10 issue of the journal Nature.


Observing occultations is a widely known method for studying foreground objects by monitoring the light of background stars. The rings of Uranus were first discovered during an occultation of a star by Uranus. But never have such small objects been detected this way.


"The interesting thing here is that instead of monitoring optical stars, these authors monitor light from an X-ray source since X-ray detectors can record light at small time intervals compared to optical detectors," Cooray told SPACE.com.  "A 100-meter body only occults a background source for about 10 milliseconds and optical detectors cannot record light continuously at such small time intervals."


Based on this finding, the researchers estimate that the number of TNOs reaches around a quadrillion, rather than the mere billions to a trillion as previously thought.


This shows an extremely dense disk of material at the outer edges of the solar system mostly populated by smaller bodies, Cooray said. "Since these are leftover material from the solar system formation process, it says that the original disk from which the planets formed was more massive at distances around Neptune than previously suggested and in strong conflict with some of the early models for the formation of Kuiper Belt Objects."

[Nemesis]

I don't know if you read any Sci Fi but I recently read the novel Building Harlequin's Moon (now available in paperback) which details the construction of a habitable moon in the Gliese 581 star system.  The novel is already obsolete because of the planet found in the habitable zone when the book says there isn't anything there.  But the planet building section is interesting, it takes the characters 60,000 years.

[Stormbringer]

cool

[Commander Maxillius]

Why would you need to build a planet?  I would think a structure like a Dyson's Sphere would be more economical.  You need only build a shell and stick a radiant power source in the center.

[Nemesis]

The Dyson Sphere is a rather misunderstood concept.  Freeman Dyson who originated the concept had the idea that any technological civilization would eventually need the entire energy output of their sun and would construct a "shell" around it as an energy gathering device.  The shell as he envisioned it would not have been solid but would have been composed of objects in orbit that collectively at all times would be intercepting the whole of the electromagnetic spectrum.  It was never intended to be lived on.

With a solid Dyson Sphere you either need to rotate it for gravity in which case all the air will be in a narrow band around the equator or use gravity generators.  One generator failure and all your air is flowing into space.  Also no nights and no seasons.  Many plants and animal species would have to be genetically reengineered to survive in the environment over the long term.

The SciFi novel Second Genesis contains a good description of such a non continuous Dyson Sphere.

For living on Nivens concept of a Ringworld is much better though you do need to have something to keep the sun centered.