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Author Topic: How do you go near light speed?  (Read 2449 times)

Offline ScientificSorcerer

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How do you go near light speed?
« on: 31/08/2014 18:00:36 »
How do you travel near light speed?



The reason why I ask this question is because interstellar distances are unimaginably vast and if astronauts are ever to get to the nearest stars in practical time then near light speed is required.

For example the nearest stars to our sun are the alpha centauri stars A and B + a dwarf star, alpha centauri a binary star system and is around 4 light years away. If we were to use rockets to get there it would take around 75,000 years.

To be honest the problem of getting near light speed isn't very complicated. All you need to do to approach light speed is constantly accelerate.  rockets can't constantly accelerate (they run out of fuel) and end up drifting from place to place.

All you need is a propulsion system which can continually accelerate, if you can do that then you will eventually get to near light speed but how do you do that? So far nobody really knows, but one thing is for sure. you can't use rocket fuel.

You would most likely need to use the energy around you to propel yourself.  For example you may need to utilize the photons around you and the charged particles in solar wind as means for power and propulsion.  By using the abundant resources around you, you wont ever run out of fuel and be able to propel your self faster and faster.

For example, what if you could use solar panels to collect electrical energy then convert that electrical energy into thrust. or you could use solar sails

Another example would be to use ionizing radiation as propulsion.  Imagine if you could collect alpha particles and thrust them out the back of your space ship at high energy, that would give you propulsion.

I don't know to be honest, those are just some examples but maybe you guys have ideas for continuous propulsion. If you do please reply below.
« Last Edit: 31/08/2014 18:04:58 by ScientificSorcerer »


 

Offline syhprum

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Re: How do you go near light speed?
« Reply #1 on: 31/08/2014 21:19:30 »
As you approach light speed the 2.7K CMBR will appear as Gamma radiation which will be uncomfortable for the occupants of the space ship
 

Offline evan_au

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Re: How do you go near light speed?
« Reply #2 on: 31/08/2014 22:21:28 »
Quote
if you could use solar panels to collect electrical energy then convert that electrical energy into thrust

The current Rosetta mission is solar-powered, but when it was "catching up" with the comet, its orbit took it out near Jupiter. At these large distances from the Sun (5 times further than Earth) sunlight is very dim (25 times less than on Earth), and the space probe had to enter a "hibernation" state in order to maintain minimal temperatures in this very cold environment. This left no spare power for communication, scientific research or propulsion.

Outside our solar system, solar power is negligible, so some form of nuclear power would be required.
 

Offline yor_on

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Re: How do you go near light speed?
« Reply #3 on: 31/08/2014 23:53:50 »
It's a nice idea but I don't think you can. It's as Syphrum writes, the light becomes gamma radiation. Unmanned small probes should have a better chance possibly? On the other tentacle, if you can find some way to make worm holes :) or something similar. Can't use any principle for inflation or expansion I think, even if we knew how to 'do it'.
 

Offline PmbPhy

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Re: How do you go near light speed?
« Reply #4 on: 01/09/2014 00:23:30 »
Who said that you can't travel near light speed using a conventional rocket? It's possible, just impractical. You'd have to have a crazy large rocket in order to store all the fuel you need for accelerating.

Regarding safety concerns regarding radiation, I read recently that they're coming close to solving that problem. If I can then I'll find where I read that and post the link.
 

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Re: How do you go near light speed?
« Reply #4 on: 01/09/2014 00:23:30 »

 

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