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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p> </o:p></span></p><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> extropy-chat [mailto:extropy-chat-bounces@lists.extropy.org] <b>On Behalf Of </b>Stephen Van Sickle<br><b>Sent:</b> Friday, April 15, 2016 2:43 PM<br><b>To:</b> ExI chat list <extropy-chat@lists.extropy.org><br><b>Subject:</b> Re: [ExI] Breakthrough Starshot - To The Stars!<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal><i><span style='font-size:9.5pt'>I know of no examples that are single mission organizations with nothing to do (and thus, no reason for people to continue participating in or remember them) for years at a time.</span></i><o:p></o:p></p><div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='font-size:9.5pt'>Why would they have "nothing to do?" The major cost is in engineering and the capital cost of the laser array. Keep sending probes. Use the laser array for other uses such as a telescope array, or much slower (and massive) local spacecraft, or super lidar for astronomical uses.</span><o:p></o:p></p></div></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='font-size:9.5pt'>Now there is a thought. Why bother with a payload? What could you see with a 100 GW laser array and the telescope array that goes with it, using it as lidar? The "probe" would be 5 times faster. And you can gather data for far longer than 2 hours.</span><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='font-size:9.5pt'>I leave the calculations as an exercise for the students. Anyone? Anyone? Spike?</span><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='font-size:9.5pt'>steve</span><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div></div><div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Steve I have been on vacation without enough bandwidth to pull the petals off a daisy, so I haven’t followed the discussion much. <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>If we are talking about using a telescope array to focus a laser over a long distance to accelerate a probe, ja the same array can be used to gaze at a distant patch of sky in the direction the probe is being pushed. You could do both at the same time: photons don’t bother each other coming and going at the same time.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>I am not sure that is what you meant however.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Tomorrow I get the mighty info pipe back.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>spike<o:p></o:p></span></p></div></div></body></html>