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General Epistemology        Chapter VIII-7       


VIII-7 The interstellar travel



There are several ways for travelling in the Interstellar space: transporting people, transporting computer coded genomes into inseminating probes, or transporting knowledge in repositories. The study of this chapter is made using the today known physics, but speculative physics is also considered at the end of this chapter

Transporting people

(Permalink) Transporting people is a huge endeavour, as it requests to launch a vast life support system, and people to live during millennia inside. Many authors envisioned it, but few weighted the real challenges. It also requests thermonuclear fusion, a thing which is still speculative. Even so an interstellar spaceship would need to carry 30% of its weight into nuclear fuel. Star Wars is still very far.

By the technologies known today, building such a spaceship would need a good part of the world economy and resources. So this is possible only for an united world, having solved the idiot competition between countries, and with a larger economy power than capitalism, that only the ego-free True Economy can provide (chapter VI-8).

In more, many technological developments are still necessary. In theory, they are possible, but need a lot of work to be brought to scale.

The worse technological challenge however is not the complexity and size of such a spaceship, but its reliability. A life support system implies handling a lot of corrosive substances and a lot of machine wear. Especially, nuclear reactors, including fusion ones, become rotten with radioactivity in a much shorter time scale than the thousand years of the shortest interstellar travel.

The worse challenge however is human: it is extremely hard to imagine that people will take birth, educate and live for many generations, in a very limited space where the least failure can bring the whole thing to an abrupt end. Today psychoprimitive Earthlings would need a tight dictatorship control. However we all know that this is a very dangerous things, as dictators always refuse to relinquish their power, and they will try to keep control of the colony after the arrival, even when better conditions no longer justify their authority. In more dictators always restrict the expression and activities of people after their own mental limitations. We may think that psychoeducated people would fare better, but they this still face two obstacles: the psychological conditions in the spaceship would be harder than in a concentration camp. This requires more than psychoeducation: that all the passengers are saints. Second, psychoeducated people will simply refuse do board a spaceship in such dreadful conditions.

In more, these conditions will have to be maintained over many generations, multiplying the occasions of failure by as many.

Worse, upon arrival, if the target planet shows too harsh to be colonized, then the spaceship cannot take over to another one. And the people jailed inside will realize that they are doomed forever to live like this, including for their descendants.

Last but not least, we can imagine that these people bring plants seeds and bacteria with them. But they cannot bring «animal seeds»: only a very small number of species will have to be grown during the whole travel. So the resultant ecosystem, upon arrival, will be very restricted.

The solution to this is to code the genomes of these animals and plants into computer files. But once this done, people too can be coded in this way, and there is no more any point at bringing living people. Which brings us to the second method:

Insemination probes ©

(Permalink) (note 93 on the use of ©) Insemination probes are only carrying computer memories, containing the genomes of a lot of species. They also need a resuscitation machine, able of converting back these genomes into living cells. (Precedence claimed here, starting 2013).

They are much simpler, and much smaller too, making them possible for us now. (However this is still a large endeavour, needing to stop the idiot competition between countries). At last, the absence of living people, and even of any moving parts, make that they can cruise much longer, and thus go much farther. In more, once one is built, many others can be built too at a much lower marginal cost, increasing the chances of reaching an inhabitable planet by sending a lot of them.


There are still many stringent limitations, though. Not the least being that an human ovum is not enough to recreate an Human. An Human person needs... parents. And education, and life support, for 20 years. So that the lander still has to bring an education system, and a life support system, even if smaller and inactive during the travel. The hugeness of such a system unfortunately brings us near the previous case of transporting people. Worse, it has to be landed on the target planet!


A solution however appeared recently (2015-2016): 3D printing of living bodies (Precedence claimed here, March 30, 2016). The advantage are ground shaking:

- The newly printed person is able to work in some days, without a long education process.

- Building a brain with an already created connectome can make the newly created person already educated, knowing to speak, skilled with many manual activities, and ready to learn complex activities, drive vehicles, handle instruments, etc.

- But especially, the newly printed persons can be natively psychoeducated, and at once start a stable and harmonious community, without the risk of a conflict or a dictatorship destroying this community. In facts, the advantages of printing natively psychoeducated people are so huge, that this may even replace the classical pregnancy! This could happen on Earth, soon, maybe in a century. In hope that the method is controlled by normal persons, not by the financial nobility, because the later will on the contrary use it to print working slaves and sex slaves with huge breasts. Without false modesty I can state that my book has a higher level.


On a new planet however, the challenge remains that the 3D printer, its ancillary machinery and energy source, has to bear, not only the interstellar journey, but tens of thousands years in some tungsten capsule, sheltered from the hostile elements of a living ecosphere, until the air is breathable and time comes to print animals and Humans. In this case, a lander of about a hundred tons may be enough, less than a thousand in the worse case. A still smaller lander is possible in the tons or tens of tons scale, if it creates a whole industrial fabric before being able to reconstruct a body printer.

As to the problem of landing such a large vessel, then the best solution appears to be that... the lander is a plane! And it lands on the water, near the shore. From here, it can drop its wings, deploys caterpillars and find a safe place on land.


So, in short, genetic insemination probes are in all cases a much better deal than an inhabited spaceship. And still better with body printers. Despite some remaining difficulties, they make things much easier. So we can expect that if space colonisation exists, it uses these methods. This strengthens the Fermi paradox, though: we find not traces of such probes on Earth, or even not Bracewell probes in our vicinity.

Star hitch hiking

(Permalink) This is a peculiar case of interstellar travel: at the occasion of a close encounter of our sun with another star, interstellar travel could be much easier. This would allow to send first automated probes, in order to start the bioforming process, and later passengers ships, which then find an already inhabitable and industrialized world.

The efficiency of such a process much depends on the rate of such close encounters, which in turn depends on the place in the galaxy. In more, the target system must have bioformable planets, which further reduces this rate. In the whole Earth history, such encounters were probably few. If they were common, then likely the solar system would have been broken by one, and we would not be here. Although the abrupt ending of the Titus-Bode series beyond Neptune, and the presence of some «intruder» carbon bodies, may be the consequence of such an encounter. If so, when it happened, the distance of the next inhabitable world was only twice the distance of Neptune, or even less. This makes the jump possible in an human lifetime, with a small passengers ship, while unmanned ships also send machines, seeds and frozen ovums.

To be noted that such star encounters will certainly happen, in the three billion years available for Mankind. Which offers us a real mean to swarm on other planets, even without thermonuclear propulsion.

However in globular clusters, in the centre bulb of our galaxy, or in small galaxies, star encounters are much more common, to the point that we discounted these dangerous places in our probability of finding inhabitable planets (chapter VIII-3) But there must be zones where star hitch hiking would be possible often enough to allow for a wide spreading of a given civilization. This would also allow civilizations to escape the deadly star encounters which destroy solar systems. And of course to survive the end of their own star.

Star surfing

(Permalink) This is also an useful interstellar navigation technique: using stars for gravitational assistance, to reach others. This would allow for an Interstellar probe or spaceship to go faster, or farther, and thus increase their chances of finding suitable planets.

The most suitable candidates for this are... white dwarves. Two reasons:

- They cleared their surrounding of all the dust and asteroids, so that it is safer to approach them.

- They can be approached much closer, due to the much lesser heat emission. Indeed, an interstellar probe passing at 250km/s through the solar system at safe distance of the sun (say some 50 millions kms) would go straight through without any large deviation. But at 300,000kms of a white dwarf, the much stronger gravitation field allows it to do a complete u-turn if needed. This can be used to accelerate, turn, or even to brake for the approach of the target star.


A variant of this idea appears for instance with an Earth probe like the Daedalus project, which was envisioned to explore the Barnard star. But Barnard is a solitary: a gravitational slingshot around Proxima Centauri may also allow to explore Alpha Centauri, with the same spaceship. Similarly, an assistance with Sirius B will allow to also explore Sirius A, and even to brake at its approach.

I claim precedence for star surfing, from October 10, 2014, in a fantastic storytelling in Inworldz, that of course everybody knows.

Target planets and colonisation plan

(Permalink) Not every planet can be colonized.

First of all, a planet must have correct physical and chemical conditions. But if so, it may already have developed life of its own...

So that a second condition is that life has not already started on the planet. Besides the obvious ethical problem of invading a world and destroying its own evolution, there is a stringent practical reason: once there is life on a planet, it is impossible to eradicate it (at least in a way which still allows for the colonists to live in). So that the colonists would in fact live in a world ridden with diseases, poisonous plants or stinking matters (to their senses). A nightmare. This reason alone may explain why Earth was never colonized, even if immoral civilisations had the occasion to do so.


This problem makes that networks of colonized planets may not be so numerous, or not so pervasive. Although one is enough to populate a galaxy: scientists evaluated that only some millions years is enough to create one.


A possible solution is that colonizing civilisations target very young planets, with good conditions, but without life yet. Still this is not ideal, because the conditions in young solar system may be unstable.

Another solution is that they colonize planets of large stars, even knowing that they live only some tens of millions years. Still a good bargain for a fast development plan and planned moving to other such planets before their sun explodes. In more, from here they can launch further expeditions toward more stable planets. This makes possible (both ethically and technically) a network of high technology colonized planets among large stars, making of them the best place for SETI to find intentional or unintentional signals.

The challenge of energy

(Permalink) There is no energy in space, and only few available on a non-industrialized planet. However a spaceship requires huge amounts of energy, and any lander will need a constant supply for many years.

The only strong enough sources known today are nuclear.


More precisely, the only thing we know to do is nuclear fission. Still it has lots of inconveniences, especially the pollution it creates preclude its use on the surface of a planet. Worse, a fission reactor produces a lot of neutrons, which make its very structure rot in some tens of years, not to speak of the delicate electronics of a spaceship.

This still makes a fission exploration probe possible, with the technologies we know today. Uranium can be extracted from the mines which were discovered on the Moon (since the mines on Earth are now nearby empty). Given the short useful lifetime of nuclear reactors, but their high power, they could work during the acceleration and deceleration phases. Proposed technologies are:

- Zubrin's salty rocket: uranium salts are dissolved in water. The reaction takes place when jets of this water meet in a combustion chamber. A rough but powerful method. My contribution is to surround the main jets with jets containing lithium or boron salts, to increase the impulse.

- Things like dust plasma reactors, where electrically charged uranium dusts float in a chamber. More durable than classical reactors, since it much less depends on some exquisite metallurgy, but more speculative.


Nuclear fusion is also theoretically possible, but yet we were unable to run any, and we have no proofs that this is actually possible.

- Most of the efforts were put in magnetic confinement (tokamaks). If ever this works some day, it will be a huge machine, and more polluting than a fission reactor, from the huge neutron flux. In more a significant part of this neutron energy arrives in the superconducting coils, making their cooling impossible once a significant reaction starts. My guess is that none of such machines will ever enter in production, or even run more than some seconds at full power.

- Other fusion methods still have to show their efficiency, without the need of a huge machinery: IEC tubes, laser confinement, etc. Currently they are even farther from production than tokamaks. But here at least, good surprises are still possible.

- Aneutronic fusion requires more rare resources, like lithium and boron, and still more energy to start the reaction. But it produces much less pollution, making it more suitable for a long cruising interstellar probe.

My personal speculations would be: (precedence claimed on April 2016)

-An atom force microscope would push hydrogen atoms inside the electron shell of a large atom. The strong electrical forces would then allow them to fusion. This was the proposed principle for cold fusion, and it would work better than the electrolysis process tested until now. A variant would use covalent chemical liaisons, not between the outer electrons, but between the electrons of the inner shells of large atoms, if ever such a thing is possible. Hydrogen atoms trapped this way may be pulled close enough to fusion, as in the muonium.

-In naive presentations of nuclear fusion, hydrogen atoms are slammed against each other, for instance with two opposite proton beams. This does not actually work, since the protons are so small that they just whizz past each other. In more they are dispersed, wasting the acceleration energy. But a very accurate electromagnetic optics would allow them to actually encounter.


I do not know if ever such methods will work. But if they do, they will provide with small yet efficient thermonuclear cells, of small power but working for a long time, able to accelerate an interstellar probe with a better impulse than fission. They may even allow for operating a lander, until more classical local energy source can take the relay.

If this does not exist at all, then we cannot expect to find any Bracewell probe, paleoartifact and the like. But still a lot of electromagnetic emissions for the SETI.

Interstellar travels with unknown physics

(Permalink) Of course Star Wars style spaceship would erase all the limitations above, by allowing fast travels of persons and unlimited cargo capacity. This however creates a very strong Fermi paradox: such a huge activity would be noticed on Earth. Space travels would be ubiquitous, and there would be all sorts of people using them, with many different motives, so that one day or another they would show up on Earth (That is, they would already be here for long). Also, the only practical results of SETI to date, is precisely that there would not be such a huge technological civilisation in our galaxy.

I would however not deny the possibility that some objects would be precisely such remnants of extraterrestrial visits (Chapter VII-5 on paleoartifacts).

To be remarked that the fields of UFOs and paleoartifacts are heavily polluted by a huge amount of conspiracy theory and cook stuff. In a science study, we even not need to mention these things. However we noted here (AZF) that such an intense propaganda activity can be the effect of an ongoing active boosting disinformation effort, aiming at censoring some real information, already released or yet to come. As proof, the media which spread this stuff also propagate climate denigration, racism, economy austerity, etc. So that nobody can swear of nothing.

Interstellar travels using UFO

(Permalink) The hypothesis as what UFOs are alien spaceships, using some unknown technology, suffers of the same contradiction: space travels would be ubiquitous, and easily noticed.

Well, precisely, UFOs were noticed...

At least, them are noticed, while no other of the hypothesis above is supported by any observation.

However the hypothesis we preferred in chapter VII-2, is that they would not be machines, and even not spaceships. Instead, they would be accidental interferences of the consciousness world into the physical world (psychical hypothesis). This makes that they are not intrinsically extraterrestrial visits. However this does not totally preclude an extraterrestrial consciousness to use this phenomenon to manifest on Earth. But as it is known today, the UFO phenomenon (or a possible spiritual technique allowing to master it) does not allow these visitors to stay on Earth, and all the more not to bring physical bodies or physical objects. To such an extent that we even not know any (proven) object coming from an UFO! Even not any (proven) message, beyond immediate reactions to the witnesses, like responding to light flashes This is troubling, and it will be discussed in chapter VIII-9 about why people able to contact Earth may refuse to actually do it.







General Epistemology        Chapter VIII-7       







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