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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><b>From:</b> extropy-chat <extropy-chat-bounces@lists.extropy.org> <b>On Behalf Of </b>William Flynn Wallace via extropy-chat<br><b>Subject:</b> [ExI] silly question<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Comic Sans MS";color:black'>Suppose you are on another planet which has an atmosphere. Will the skies be blue?<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Comic Sans MS";color:black'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Comic Sans MS";color:black'>bill w<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Rayleigh scattering is a function of the chemical composition of the atmosphere as well as the density profile.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Every planet has an atmosphere. Even Mercury has an atmosphere (not much of one, a trillionth of ours perhaps.)<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Venus has an atmosphere, but skies there are white if you are high enough, probably nearly black from down at the surface.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>If a planet has an atmosphere like ours with a gravitational field like ours and is a similar distance from a star like ours, good chance that planet would have blue skies.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>spike<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p></div></div></div></body></html>