Text 519, 58 rader
Skriven 2006-05-25 07:56:00 av Robert E Starr JR (965.babylon5)
Ärende: Re: Do we need artificial
=================================
* * * This message was from Andrew Swallow to rec.arts.sf.tv.babylon5.m * * *
         * * * and has been forwarded to you by Lord Time * * *         
            -----------------------------------------------             

@MSGID: <NeCdnVYxKP-1zu3ZRVnyvw@bt.com>
I have been looking at the food requirements of a 4 year trip to Mars. 
For 6 people they will have to carry 14 metric tons of food.  I suspect 
that there is insufficient room for that much food in the CEV.

From
http://pet.jsc.nasa.gov/documents/simaDocs/FY02Metric.doc
Advanced Life Support Research and Technology Development Metric ~V 
Fiscal Year 2002, JSC 60313 A
See section 3.4.1.1.2

Food per pay per person = 1.61 kg (as used on International Space Station)
Number of people = 6
Number of years = 4
Days in year = 365
Kilograms in a metric ton = 1,000

Total weight = 1.61 * 6 * 4 * 365 / 1,000 = 14.1 metric tons.

The astronauts are going to need either a bigger vehicle or a heavy 
transporter to deliver the food.

The food will also need keeping fresh for 4 years.



The planned heavy lift cargo launcher can lift 106 metric tons to Low 
Earth Orbit (LEO).  We can get a reasonably sized Moon/Mars base along 
with furnishings and food with a weight limit of 106 metric tons.  A 
chemical rocket to put that in moon/Mars orbit would be enormous and 
shipping it in separate 21 ton trips will cost a major fortune.

NASA was developing several rival methods of ion propulsion able to move 
large loads over long distances using only small amounts of propellent. 
  Pity Project Prometheus was cancelled earlier this year (2006).  That 
will have probably stopped the development of nuclear propulsion.  Solar 
powered propulsion already exists and could still be scaled up by the 
private sector, its is viable when solar panels can produce a half to 
one mega Watts.

1.Solar powered rocket
   http://www.grc.nasa.gov/WWW/RT1999/6000/6920kerslake3.html
   http://www.entechsolar.com
2.Magnetoplasmadynamic thrusters
   http://www.nasa.gov/centers/glenn/about/fs22grc.html
   http://www.adastrarocket.com
3.Hall effect thrusters
   http://www.grc.nasa.gov/WWW/ion/present/hipep.htm
   http://www.aerojet.com

Andrew Swallow
                                                                    
--- SBBSecho 2.11-Win32
 * Origin: Time Warp of the Future BBS - Home of League 10 (1:14/400)