[ RadSafe ] Fission, Fusion, Mars, Spacecraft...

[Maury Siskel]

Is it possible that doing away entirely with patrol boats and simply 
using NP cruisers  for that function might be an optimum solution?
Best,
Maury&Dog    [MaurySiskel maurysis at peoplepc.com]
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On 3/26/2013 10:23 AM, Brennan, Mike (DOH) wrote:
> Hi, Joe.
>
> Given that I will be attending a science fiction convention this weekend, and one of the panels I am on is about spaceship combat, I've given a fair amount of thought to things like this.
>
> With current, or near term technology, getting mass into orbit is the expensive part.  This is the first big problem with using some type of nuclear reactor for propulsion in space: there is a minimum size you can make a reactor, and it is fairly big.  When you include the reactor, its
> auxiliary systems, and the reaction mass, you need a very large system before it has higher energy density than a chemical rocket system.  To use a down-to-earth example, it is clearly a good idea to make aircraft carriers nuclear powered, it is a reasonable idea to make cruisers nuclear powered, it makes no sense at all to make patrol boats nuclear
> powered.
>
> When thinking about space travel, it is important to not confuse acceleration with velocity.  The propulsion plant determines what acceleration your ship is capable of, but velocity is only limited by time and reaction mass/fuel.  (yes, I can hear you shout, "But what about relativity!"  By the time you can sustain accelerations that get
> you to relativistic velocities in fairly short lengths of time, you are not working with anything we could build with our current understanding of physics).  I don't foresee us building a ship where acceleration will be a challenge for people (once it gets out of the gravity well, of course).
>
> I love nuclear power in space, but we are at least two scientific breakthroughs away from needing it for manned ships.
>
>
>
> -----Original Message-----
> From: radsafe-bounces at health.phys.iit.edu
> [mailto:radsafe-bounces at health.phys.iit.edu] On Behalf Of
> JPreisig at aol.com
> Sent: Monday, March 25, 2013 10:07 PM
> To: radsafe at health.phys.iit.edu
> Subject: [ RadSafe ] Fission, Fusion, Mars, Spacecraft...
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