From: spam@merlyn.demon.co.uk   
      
   JRS:  In article <3FEFAAC4.1A31@ix.netcomARGH.com>, seen in   
   news:sci.space.tech, Scott Lowther  posted at Mon, 29 Dec 2003 04:17:09 :-   
   >   
   >Alternatively... if you wanted to get to Jupiter in 3 months, or six   
   >months, and you had an arbitrarily short thrust time (i.e. high thrust   
   >system), how fast would you have to go? And how fast would you be going   
   >at Jupiter?   
      
     Earth's orbit radius ~ 150 Gm   
   Jupiter's orbit radius ~ 750 Gm   
   Distance ~ 600 - 900 Gm   
   Take worst case ; 900 Gm in 90 days is 10Gm / day.   
   One day is 0.1 Ms (-15%)   
   Hence speed required is 0.1 Mm/s   
      
   That's reasonable, since IIRC Ulysses took something like 15 months,   
   implying 20km/s, which seems feasible.   
      
   As you described it, you would be going 0.1 Mm/s if you did not want to   
   stop, or were using Jovo-braking - and, I suggest, nearer 0.0 Mm/s if   
   you did want to stop gently.   
      
   Earth's speed is about 30 km/s - so a significant navigational   
   correction hardly affecting the principle.   
      
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