Here's an overview of ideas presented in my Interstellar Transportation proposal which uses current technology (including reasonable expectations for near term improvements) for the most part. By attempting to implement this system we can enhance our survival by reducing the natural hazards that can otherwise prevent us from achieving the advanced levels of civilization postulated for our cosmic neighbors. In order to survive and evolve, sets of living organisms must alter their local environment. The sentient ones will learn to do so beneficially. Extrapolating from "Cortez and the Aztecs" we would be wise to learn to deal with non-benevolent advanced sentients while achieving and practicing benevolence ourselves.

The lone termite beholds its maturing mound incapable of awe.
One built by the termite and its moundmates driven by biological law.
Pursuing an unconscious urge within their genes constructed;
Daring humans to do what human consciousness has instructed?
These termites persist by the grace of the aardvark's claw,
And humans thrive by that of the asteroids orbits' pitch and yaw.
Ever looking askance anticipating the supernova's power raw,
In anxious quandary about the skewed orbit of a black holes's maw
And not unmindful of patient earth's restless crust's upheaval;
Knowing each can place this single basket of humans beyond retrieval.



ABSTRACT
An operational concept for developing and implementing interstellar transportation and exploration as well as enhancing travel to and the colonization of the solar planets is described. The Alpha Centauri System can be reached within 10 (where 40 years is a piece of cake) years after trip initiation from the Solar System. Exploration of the entire Milky Way galaxy is achievable as the system expands from star to star. Vehicle velocity profiles with greater than 0.5 light speed have been tabulated including the power levels required. The method of acquiring this power is outlined. The design uses propellant exhaust rates on the order of a few hundred kilograms (rest mass) per second, expelled at relativistic velocities, and photon sail effects. The assumption is made that this much mass is available in interplanetary and interstellar space or can be made available via soloton-like particle beams radiated from the trip initiating star. High level system requirements and design approaches are included.

OPERATIONAL CONCEPT
This operational concept is for interstellar transportation, solar and extrasolar planet colonization, and the exploration of distant stellar systems. It requires a system comprising 4 independent interfacing major elements as presented in the system description. This concept defines the starting point that is expected to require benefit of the knowledge gained from its evaluation and implementation.

CONSTRAINTS
Propellant exhaust velocities (Ve) must be an appreciable fraction (0.3 to 0.5) of the speed of light to minimize the total propellant mass.

The propellant exhaust velocities produced by chemical combustion processes are orders of magnitude smaller than 0.3c therefore, chemical combustion processes are ruled out of consideration for interstellar distances.

Fission processes at the required energy levels are too mass intensive.

Fusion processes for the required energy levels are currently out of reach
and are likely to remain so for 250 or more years.

Matter/antimatter propulsion processes capable of providing energy at the
required levels will defy our cleverness for yet another two or more centuries.

Zero point vacuum energy harnessing and wormhole exploitation processes
are too heavily invested in imagination to merit serious consideration.

The nearly perfectly collimated beamed energy must be sufficient to provide 10^17 to 10^19 watts and the receiving surface must be as small as it can be and acommodate power densities on the order of .01 to 10 megawatts per square meter. The design goal is to limit the mass of the receiving surface including its support structure to no more than than 99% of the total mass of the vehicle.

D. Sole sail is a soul sale. Plasma rocket propulsion is required to achieve the desired orbit at the destination stellar system.

ASSUMPTIONS
A. Photovoltaic efficiencies of 50% or greater will be available within 20 years.

B. Material and or processes can be selected (or developed) to accommodate the
mass to thrust ratios and power density characteristics required by the
system descriptions.

C. The system can be extended from each stellar system to the next by either
transporting the essential components from “the next star back”
or manufacturing them in place where suitable natural platforms (planets
and/or their moons) are found or can be assembled.

D. Sufficient material exists in interplanetary and interstellar space to supply
the propellant mass required for propulsion. It is the nature of the
gravitational forces at play in each stellar system to cause cometary and
asteroidal objects and materials to be expelled into galactic orbits thus
providing both propellants and hazards. What we think of as the Oort cloud
may turn out to be, or more likely, merge with "a continuum" of material in
galactic orbit among the stars.


The earth is but humanity's cocoon precariously attached to the solar system which is but a twig on the galactic tree. Now is the time for the imago to emerge and explore the tree----and eventually, its neighbors. Shall our dreaming limit our vision of progress to having our descendants do less than engineer the expansion of the universe...with appropriate deference to the will and grace of God of course?

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For those inclined to oppose human meddling with the structure of the universe or the composition and configuration of objects and groups of objects within the universe, consider:
Whether there is a limit to the magnitude of a modulation of chaos below which order remains invariant? Or, is order but a fiction invented by perspectives applied over finite, however large, time intervals?

Good piece of work!

But some of the things you outlined we might not discover how to utilise for 30 or more years, is that still classed as in the near forseeable future? I do not know.

But we may discover things like false vacuum, tomorrow, all it takes is for someone to come up with a really, really clever idea and develop it. Like Einstein did. Its unlikely though...

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MacTalk - The Australian Apple Community - iPod, iPhone and Mac.

isn't it weird that we try to prejudge another civilization that doesn't exist by our expectations that change every day.

It's not only not wierd, it's the only way open to us. Extrapolation from where we are and what we know, and what we can easily imagine, are our only tools and quite valuable. It puts us in a better position than are slugs and earthworms and maybe even most other primates.

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For those inclined to oppose human meddling with the structure of the universe or the composition and configuration of objects and groups of objects within the universe, consider:
Whether there is a limit to the magnitude of a modulation of chaos below which order remains invariant? Or, is order but a fiction invented by perspectives applied over finite, however large, time intervals?

Lol. Daddy has a point though. Given the diversity of civilisations on Earth, perhaps we shouldn't be so quick to make prejudgements.

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Climate Change Australia

Au contrare! We have been and are being much too slow. Our very survival depends on our exploring the likely outcomes of contacts with extraterrestrials. Carbon based critters are very likely simply because of the nature of carbon. Intelligence and aggression go together because the more intelligent anticipate dangers, alas sometimes falsely, and attempt to posture themselves to avoid their own destruction leading to the conclusion that the best defense is the best offense you can employ. From the most general of perspectives the civilizations of the Inca and the Aztecs, except for more primitive technology and barbaric religious practices, were not that different from that of the European states.

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For those inclined to oppose human meddling with the structure of the universe or the composition and configuration of objects and groups of objects within the universe, consider:
Whether there is a limit to the magnitude of a modulation of chaos below which order remains invariant? Or, is order but a fiction invented by perspectives applied over finite, however large, time intervals?

A truly fascinating article.