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</o:shapelayout></xml><![endif]--></head><body bgcolor=white lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:windowtext'>From:</span></b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:windowtext'> extropy-chat [mailto:extropy-chat-bounces@lists.extropy.org] <b>On Behalf Of </b>Anders Sandberg<br><b>Sent:</b> Tuesday, December 22, 2015 12:12 AM<br><b>To:</b> ExI chat list <extropy-chat@lists.extropy.org><br><b>Subject:</b> Re: [ExI] space-x sticks the landing<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>On 2015-12-22 07:30, spike wrote:<br><br><o:p></o:p></p><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><p class=MsoNormal style='background:white'><span style='font-size:10.0pt;font-family:"Helvetica",sans-serif;color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='background:white'><span style='font-size:10.0pt;font-family:"Helvetica",sans-serif;color:#1F497D'>The wicked coolness is around 32 minutes and following. Tail first landings are soooo cool, I just love em.</span><o:p></o:p></p></blockquote><p class=MsoNormal><br><span style='color:#1F497D'>>…</span>Beautiful.<br><br><span style='color:#1F497D'>>…</span>In the pictures it looks like the vehicle came in from the sea side, which makes sense from a safety perspective, but I can't figure out the orbital mechanics. <br><br><br><o:p></o:p></p><pre>-- <o:p></o:p></pre><pre>Anders Sandberg<o:p></o:p></pre><pre>Future of Humanity Institute<o:p></o:p></pre><pre>Oxford Martin School<o:p></o:p></pre><pre>Oxford University<o:p></o:p></pre><pre><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></pre><pre><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></pre><pre><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>All payloads to orbit would need to be fired eastward, but the landing sequence we saw is the endgame. There was time to bring the eastward velocity to zero and start back westward (or any other direction) without a significant weight penalty. It makes sense to do it that way, so if the thrusters or anything else fails during the landing sequence, the bird overshoots the landing site and drops into the sea rather than some litigious prole’s back yard. <o:p></o:p></span></pre><pre><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></pre><pre><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>As for deceleration, the atmosphere does most of the work for us. For the very first time in launcher history, air is our friend.<o:p></o:p></span></pre><pre><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></pre><pre><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>spike<o:p></o:p></span></pre></div></body></html>