Editing Talk:1626: Judgment Day

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:After escaping Earth's well, the nukes still have inherited the velocity of Earth's orbit. They need to reduce their periapsis close to/inside the sun. That would take extreme amounts of Delta v (i.e. energy)... [[Special:Contributions/141.101.79.43|141.101.79.43]] 16:45, 6 January 2016 (UTC)
 
:After escaping Earth's well, the nukes still have inherited the velocity of Earth's orbit. They need to reduce their periapsis close to/inside the sun. That would take extreme amounts of Delta v (i.e. energy)... [[Special:Contributions/141.101.79.43|141.101.79.43]] 16:45, 6 January 2016 (UTC)
  
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:And to those skilled at Kerbal Space Program... that uses a simplified 'nearest body rules' system for orbital mechanics.  You can (I know I have!) launched a rocket of sufficient power such that it escapes the 'back' end of the planet's influence with a pre-escape velocity somewhat equivalent to the planet's forward velocity, which is then removed as part of the transfer to 'open space', leaving it on a highly eccentric orbit (with reference to the newly supreme gravitational source) that is practically 'straight down' (though because of the Kerbal sun's nature, you still usually sun-skim it on a very tight loop back out again).  But that takes more energy than 'merely' getting beyond the planet's influence and end up travelling round the parent body in an orbit only marginally off that of the original planet, the nature (and future) of which depends completely on which direction you eventually broke free.  (NB. This was all in an older version, I think they've changed some things about what happens near the sun, but not the basic physics system.)
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:And to those skilled at Kerbal Space Program... that uses a simplified 'nearest body rules' system for orbital mechanics.  You can (I know I have!) launched a rocket of sufficient power such that it escapes the 'back' end of the planet's influence with a pre-escape velocity somewhat equivalent to the planet's forward velocity, leaving it on a highly eccentric orbit (with reference to the newly supreme gravitational source) that is practically 'straight down' (though because of the Kerbal sun's nature, you still usually sun-skim it on a very tight loop back out again).  But that takes more energy than 'merely' getting beyond the planet's influence and end up travelling round the parent body in an orbit only marginally off that of the original planet, the nature (and future) of which depends completely on which direction you eventually broke free.  (NB. This was all in an older version, I think they've changed some things about what happens near the sun, but not the basic physics system.)
 
:However, IRL you are always subject to gravity from ''every'' body.  Maybe most of the time one dominates, but there's a fuzzy interface (and zones where influences balance out, hence Legrange Points).  Think of it as still having a link to Earth's progression round the Sun, dragging you round, at least until you're at a point in opposition to the Earth, across the Sun (then it's dragging you back that way, encouraging you into a retrograde solar orbit).  Albeit that this ''too'' is an oversimplification.  But by the time you've got your rocket near opposition to its launch planet, you've expended the energies needed to fall into a non-grazing (i.e. utterly non-missing) 'orbit', and it's a ''lot'' of thrust.  Which is what is required of those boosters. [[Special:Contributions/162.158.153.29|162.158.153.29]] 17:58, 6 January 2016 (UTC)
 
:However, IRL you are always subject to gravity from ''every'' body.  Maybe most of the time one dominates, but there's a fuzzy interface (and zones where influences balance out, hence Legrange Points).  Think of it as still having a link to Earth's progression round the Sun, dragging you round, at least until you're at a point in opposition to the Earth, across the Sun (then it's dragging you back that way, encouraging you into a retrograde solar orbit).  Albeit that this ''too'' is an oversimplification.  But by the time you've got your rocket near opposition to its launch planet, you've expended the energies needed to fall into a non-grazing (i.e. utterly non-missing) 'orbit', and it's a ''lot'' of thrust.  Which is what is required of those boosters. [[Special:Contributions/162.158.153.29|162.158.153.29]] 17:58, 6 January 2016 (UTC)
  

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