Posted on 01/17/2014 7:17:49 AM PST by 12th_Monkey
Interstellar flight certainly ranks among the most daunting challenges ever postulated by human civilization. The distances to even the closest stars are so stupendous that constructing even a scale model of interstellar distance is impractical. For instance, if on such a model the separation of the Earth and sun is 1 inch (2.5 centimeters), the nearest star to our solar system (Proxima Centauri) would be 4.3 miles (6.9 kilometers) away!
The fastest object ever built by the human species is the Voyager 1 space probe, moving at a speed of 18 miles per second. If it were heading toward Proxima Centauri (which its not), Voyager 1 would reach our nearest stellar neighbor in about 80,000 years.
Clearly, if interstellar travel is to be accomplished on human timescales, much greater speeds are required. At 10 percent of the speed of light (a thousand times faster than Voyager 1, but a conceivable speed for likely soon-to-be-realized fusion engines), Proxima Centuri could be reached in approximately 45 years less than a human lifetime.
However, the necessary energies to achieve substantial fractions of the speed of light, thus cutting the travel time to the stars to less than a human lifetime, are equally mind-boggling.
Every pound of starship moving at 99.9 percent the speed of light will have a kinetic energy more than three times greater than the energy of the largest nuclear weapon ever detonated. Nevertheless, there may be a way of supplying an engine with such prodigious energies.
In his 1955 paper Geons, John Wheeler, one of the pioneers of the theory of black holes, coined the term "Kugelblitz" which translates literally to "ball lightning." He suggested that if enough pure energy could be focused into a region of space, that energy would form a microscopic black hole,
(Excerpt) Read more at space.com ...
“The fastest object ever built by the human species is the Voyager 1 space probe, moving at a speed of 18 miles per second. If it were heading toward Proxima Centauri (which its not), Voyager 1 would reach our nearest stellar neighbor in about 80,000 years.”
Coincidentally, that just happens to be the orbital speed of Earth around the Sun (~18 miles/sec, or ~66,000 miles/hr).
Give me a break. Everyone knows this is what the Romulans use, not us! Geesh!
So how do they plan to keep form running into things?
Travel at the speed of light rules out radar things. By the time you got a return form an object you would be on top of it.
Of course when you start talking about speeds close to that of light, it brings up all sorts of weird stuff like time dilation and length contraction.
Here's an explanation of time dilation that I wrote myself a few years ago. Hope it makes sense. The graphic I found on the Web.
First, from Wikipedia: "One second is defined as 'the duration of 9192631770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom'..."
http://en.wikipedia.org/wiki/Second
Now imagine, instead of a vibrating 'caesium 133 atom', we have a beam of light bouncing back and forth between two mirrors within a vertical tube. Now let's say, for the sake of argument, that it takes precisely 'one second' for the light beam to reach the top mirror (tick), reflect off it, reverse and reach the bottom mirror (tock).
Now let's say the light tube, or 'light clock', is resting on a flatbed train car, and on the flatbed is an observer who we will call "Observer A". To Observer A, who is moving along with the train and is therefore 'at rest' with respect to it, the light beam simply travels from the bottom of the tube *vertically* to the top of the tube and then straight back down again. From the relationship, speed equals distance over time, we get time equals distance over speed. So this is then how Observer A defines time (t=distance/speed). Important to note here, is, according to theory and supported by experimental evidence, light travels at the SAME SPEED for ALL observers.
Now let's say there is an observer B standing on the embankment alongside the train watching it pass by. From this observer's point of view, or frame of reference, the light beam does not simply travel vertically up and down but rather in a slanted or diagonal path, since the train is in motion, let's say from left to right as Observer B sees it. Now since the light beam travels a diagonal path between tick and tock, again, from OB's stationary point of view, the light beam therefore is traveling a LONGER distance (from OB's perspective). Therefore, since the light beam is traveling a longer distance (from OB's perspective) AND since light travels at the same speed for all observers, the light beam MUST take a longer time to bounce between the two mirrors (tick-tock). Therefore, the two observers (A and B) do NOT agree on what a "second" is.
http://galileo.phys.virginia.edu/classes/252/srelwhat.html
The mathematical relationship between the two paths is based on the Pythagorean Theorem for right-triangles that many of us used in high school.
Here is that mathematical relationship (between time as perceived by the two different observers) that is derived from the familiar Pythagorean Theorem (a squared + b squared = c squared, c being the longest leg of the 90 degree (right) triangle depicted in the above illustration):
-ETL
That is an interesting factoid that I’ve never heard before. Thanks.
My memory is fuzzy on the subject, but I think the Voyagers were the first probes to use gravity assists to get to their cruising speeds.
they need that kind of power for the cloaking device.
PFL
If you only traveling at 45% of light then I guess it would still work. But the real point is even an object the size of a pea hitting a ship at 45% of light would probably end the trip rather quickly.
Star Trek Tech used deflector shields to eliminate this pesky problem and deal with hostile aliens as a bonus. But that is just as impossible as building a singularity to power an engine.....at least for now that is.
They tried that in “Event Horizon”...it didn’t end well...
And that’s why I use worm holes for all my interstellar flight.
You can actually use that little formula in my post 5 to see how a second aboard a ship traveling at 45% light speed would compare to that of a second back on earth. Just replace v with .45c
V’ger 1 is moving at 38,000 mph which is 10.5 miles/sec. Possible confusion between kilometers and miles pet hour.
...it would also shorten the trip via ‘length contraction’, from the high-speed ship’s perspective.
“Schwarzschild Kugelblitz”
May the Schwartz be with you.
Therefore, the two observers (A and B) do NOT agree on what a "second" is.
Two questions:
1) But they would both agree one the height of the (vertical) tube, right?
2) If the tube were not oriented vertically, but rather parallel to (i.e., in line with) the direction of motion of OA, thus undergoing apparent shortening in length (as per the Lorentz Transformation) as viewed by OB, then they couldn't agree on the length of the tube either, could they?
Regards,
I think time dilation would be in full effect. If it takes 45 years to get to your destination at speeds approaching light then time dilation would mean a great deal of time would pass on earth. In fact, it would be possible for a ship with the capability to fold space (developed while the near light speed was on it’s journey) would arrive ahead of the NLS ship.
Light speed, time dilation and that kind of theoretical thinking messes with my head.
It has also been theorized that if you built one of these things and kept it fed (you have to add matter to it or else it would eventually evaporate in a BOOM) that you could use the power from on e device to start additional devices...
Basically it is just a Matter to Energy conversion engine that uses a trick of gravity to stay stable.
If you over feed it the amount of energy released actually goes DOWN... It is kinda paradoxical that way...
contraction? I thought that length theoretically increased as an object approached light? Just like matter falling into a black hole is supposed to spaghettify.
You're correct.
"As of 2013, the probe [Voyager 1] was moving with a relative velocity to the Sun of about 17 km/s.[12]"
http://en.wikipedia.org/wiki/Voyager_1
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Voyager 2:
"The probe is now moving at a velocity of 15.428 km/s relative to the Sun.[6]"
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