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Tremus
2012-May-11, 08:04 PM
I have often wondered what is really out there. We all know about comets and ice, dust, gas and the occasional dwarf planet, but there is a real mystery out in those outer reaches of our solar system that we have to consider. It may be that this will be the furthest that we as a spicies may ever reach. I dream of the stars but they are beyond us.

DanishDynamite
2012-May-15, 07:05 PM
The stars may be beyond us in our lifetimes but if we take care of our spaceship, Earth, there is no reason (physics-wise) that our descendants won't reach the stars, or the entire Milky Way for that matter. Still, in my own lifetime I would like to learn everything I can, including the mysteries that the Kuiper Belt objects will reveal.

Cosmologist
2012-Jul-26, 12:31 PM
Aren't Kuiper belt objects mostly ice comets? Sounds like a good pitstop for picking up volatiles to make rocket fuel. Very convenient for starships. All we need is a long term suspended animation system.

Shigeru
2012-Jul-27, 02:55 PM
The stars may be beyond us in our lifetimes but if we take care of our spaceship, Earth, there is no reason (physics-wise) that our descendants won't reach the stars, or the entire Milky Way for that matter. Still, in my own lifetime I would like to learn everything I can, including the mysteries that the Kuiper Belt objects will reveal.

Absolutely agree! That are exactly my thoughts, as also Sagan says, let's hope what humanity can advance to the next step.

neilzero
2012-Aug-06, 04:50 PM
If we travel away from the sun at the rate of 1000 million miles per year, = we are in the Oort cloud or outermost Kuiper belt in one century, but we need to slow to about 50 million miles per year and turn right to soft land on a rather slow orbiting Oort cloud ice ball. That is a large amount of delta v to loose to collect some resources. We may not have enough energy to resume our out bound trip even at 100 million miles per year. Our century old neuclear power plant is likely making watts instead of megawatts. Solar panels died long ago plus negligible sunlight. Our super conducting ring has one or more opens somewhere on it's 200 mile circumfrence. Our solar sail is in taters and the solar wind is much weaker than closer to the Sun. We distroyed our Orion type pusher plate matching speed with the ice ball, and have only a few half strength H bombs left. What energy source might be practical to produce significant delta v? Our craft likely has more mass than the ISS = international space station, so we have ejection mass, but almost no energy.
With incredible good luck a comet that was near the sun about a century ago may come along side at about the same speed and direction (so we don't need to slow down), but one chance in a million is extremely optimistic, as we have not yet found the first comet on a hyperbolic trajetory, so one closely matching our hyperbolic tragetory is very improbable. Neil

ASTRO BOY
2013-Jan-27, 04:10 AM
The stars may be beyond us in our lifetimes but if we take care of our spaceship, Earth, there is no reason (physics-wise) that our descendants won't reach the stars, or the entire Milky Way for that matter. Still, in my own lifetime I would like to learn everything I can, including the mysteries that the Kuiper Belt objects will reveal.



My thoughts and feelings exactly!!!!
Maybe even beyond given time.....

John F
2014-Feb-22, 10:07 AM
Aren't Kuiper belt objects mostly ice comets? Sounds like a good pitstop for picking up volatiles to make rocket fuel. Very convenient for starships. All we need is a long term suspended animation system.

Sounds like a great place to plant a colony. Each colony will house professional astronomers along with interested people living at a space colony out there. Complete sky mapping will be possible with telescopic arrays at such distances apart across the solar system. SPS beams from colonies closer in can map much of it before people get there.

As long as no critical part or tool breaks aboard the space colony/mine/factory and the life system can be made to make good use of the flying mountains of ices and stuff, people will begin testing extreme long duration trips, by going farther out; comet-hopping.
Any of many proposals that make mediocre at best starships will make just fine interplanetary/cometary colony ships; maybe up to tens of years to really distant Oort halo colonies, but only a year or so to where trans-Neptunian Kuiper belt objects are. Months to Jupiter. Trade of some extended sort can happen with tens-of years transport times. Possibly fast crewed ships can transfer genes as well as tools, all the way out into the Oort cloud and people might not necessarily be born & die in one distant habitat as a normal practice for a long time. If raw materials will be ubiquitous and cheap, think of the luxury markets in hand-crafts. What else will be worth shipping?
It leads to an extremely slow nomadic form of interstellar travel, but if long-duration self maintaining mini-biospheres can survive and carry humans as a macro-life colony, it gets us there. We (or whatever we've evolved into by then) will be all across this galaxy and into M-31 in Andromeda, long before they start colliding (\approx15Gyear)

John F
2014-Feb-22, 10:31 AM
"1000 million miles per year"
That's about 50km/sec. Nuclear pulse from the 1950s-'60s would do it, space-built and huge. Build it really extremely big (tens of thousands of tons, mag-sail coupled to the pulses of plasma, and it could reduce the trip time considerably with truly insanely fast trajectories. ISP in the millions, no physical interaction with the plasma pulses.
Easily several times the \Delta V specified. More, probably, for a stripped crew transport, loaded with bombs and propellant. Notably, the propellant whether it be ices/plastics or metals, is up to 90% of the mass of "rocket propellant" ejected. The fissionable "pits" of the bombs are less than 10%.
As long as firing circuits and everything else could be made to work, I don't know enough to bet either way that century-old Pu 238 will still controllably go critical -not that such durations are necessarily implied.
The Outer Kuiper cloud is tough to trade with, but there's plenty to grow into closer in, and there will be ships to do it with.
The colonies the ships trade with are on their paths, proceed over long time by mating with/eating a cometary body while boosting to their next rendezvous with another chunk, years in the future. The eventual bet will be that colonies can be self-sustaining with cometary materials for long enough to eventually match with something passing at low relative velocity, but that's not technically orbiting the Sun. Beyond that, they're on their own unless ships can get to them.

Ivan Bilic
2014-Jun-10, 09:27 PM
I have often wondered what is really out there. We all know about comets and ice, dust, gas and the occasional dwarf planet, but there is a real mystery out in those outer reaches of our solar system that we have to consider. It may be that this will be the furthest that we as a spicies may ever reach. I dream of the stars but they are beyond us.

You are right on that we don't know what all is there. Kuiper Belt is still unexplored area, as entire outer solar system. We could find lot of surprises there. It is not long time that we discovered Van Allen radiation belt close to our earth.

speach
2014-Jul-09, 01:03 AM
I dislike the term 'ice' this implies solid water, is that what we are talking about? If so where did it come from? Or we talking about solid methane and other materials that are a gas at earth temperatures and pressures?