home bbs files messages ]

Forums before death by AOL, social media and spammers... "We can't have nice things"

   rec.arts.sf.science      Real and speculative aspects of SF scien      45,986 messages   

[   << oldest   |   < older   |   list   |   newer >   |   newest >>   ]

   Message 45,334 of 45,986   
   Thomas Koenig to dsdy120@gmail.com   
   Re: Revisiting the Gravity Gauge   
   11 Mar 18 19:27:40   
   
   From: tkoenig@netcologne.de   
      
   dsdy120@gmail.com  schrieb:   
      
   > Several assumptions for the following calculations:   
      
   > 1. Planet is airless and nonrotating   
      
   OK.   
      
   > 2. Attacker occupies circular orbits only.   
      
   Hmmm...   
      
   > 3. Defender fires projectiles straight upward - this makes sense   
   > because defenders only care about altitude - not velocity. Anything   
   > above 1 km/s generally starts becoming a bad day for either   
   > combatant   
      
   No, this does not make sense.   
      
   Asuume you're in LEO, at 7.9 km/s.  You have 3.3 km/s delta v at   
   your disposal.   
      
   Now, you can add that delta v tangential to your velocity, giving you   
   escape velocity, so you can hit everything in orbit around Earth.   
      
   Alternatively, you can add the delta v perpendicular to your   
   current velocity.  According to Phythagoras, this will give   
   you a combined velocity of 8.56 km/s, so you get only 0.66 km/s   
   additional velocity.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)   

[   << oldest   |   < older   |   list   |   newer >   |   newest >>   ]


(c) 1994,  bbs@darkrealms.ca