# PLAN[E]T ENGINEERING 101 *The Urth list — 3 messages, 2 voices, 26 Nov 2002* > Exported from an unofficial mirror of a public mailing list. Copyright > in each message remains with the person who wrote it. > Email addresses are obscured as `user at host`, the form the original > archive published. This file was rebuilt from parsed fields rather than > retained headers, so it is faithful in content but not byte-exact. --- ### Dan'l Danehy-Oakes *26 Nov 2002, 17:17* Ahem. It seems to me that we can explain the difference in climate between Green and Blue, without resorting to a radical difference in their respective orbits ... for example, by invoking a difference in the chemical composition of their atmospheres. Suppose that Green simply has a very high percentage of "greenhouse gasses" -- including but not necessarily limited to CO2? And that Blue has a relatively low percentage thereof? Or put it in terms of albedo, and say that Blue's is higher than Green's, so that the same amount of incident solar raditation produces a higher degree of insolation. Will that not produce the -- relatively small; they're both "life zone" planets! -- difference in their average surface temperature? Frustrated, --- ### Charles Reed *26 Nov 2002, 17:41 · follows Dan'l Danehy-Oakes* Ahem back. You're right, of course. My training is in mathematics, not geological/planetary science. Still, I should have thought of that. My tendency seems to be jumping in with my "ideas" without fully examining other alternatives. Still, there's no denying that even if Green orbits Blue, it doesn't orbit it in the same way that Lune orbits Urth. That was one of the points I was trying to make and I got sidetracked talking about orbits and such. Sheepishly, Charles > Dan'l Danehy-Oakes wrote: > Ahem. > > It seems to me that we can explain the difference in climate between > Green and Blue, without resorting to a radical difference in their > respective orbits ... for example, by invoking a difference in the > chemical composition of their atmospheres. Suppose that Green simply > has a very high percentage of "greenhouse gasses" -- including but > not necessarily limited to CO2? And that Blue has a relatively low > percentage thereof? Or put it in terms of albedo, and say that Blue's > is higher than Green's, so that the same amount of incident solar > raditation produces a higher degree of insolation. Will that not > produce the -- relatively small; they're both "life zone" planets! -- > difference in their average surface temperature? > > Frustrated, > > --Blattid --- ### Dan'l Danehy-Oakes *26 Nov 2002, 18:23 · follows Charles Reed* Charles, I didn't mean to direct my Ahem at you; you are hardly the first to get involved in the orbit trap in discussing the mechanics of the Bleen system. I've seen some of our smartest list members go on at great length about possible orbits (including some extreme cases like a sort of W-shaped orbit that actually works but that I really doubt would be stable for a planetary pair for any long period of time). Nor had I thought of this possibility prior to today, so I'm not claiming any special credit for brilliance here ... > -----Original Message----- > From: Charles Reed [mailto:cmreed at link.com] > Sent: Tuesday, November 26, 2002 9:41 AM > To: urth at urth.net > Subject: Re: (urth) PLAN[E]T ENGINEERING 101 > > > Ahem back. > > You're right, of course. My training is in mathematics, not > geological/planetary science. Still, I should have thought > of that. My > tendency seems to be jumping in with my "ideas" without fully > examining > other alternatives. > > Still, there's no denying that even if Green orbits Blue, it doesn't > orbit it in the same way that Lune orbits Urth. That was one of the > points I was trying to make and I got sidetracked talking > about orbits > and such. > > Sheepishly, > > Charles > > > > Dan'l Danehy-Oakes wrote: >> Ahem. >> >> It seems to me that we can explain the difference in climate between >> Green and Blue, without resorting to a radical difference in their >> respective orbits ... for example, by invoking a difference in the >> chemical composition of their atmospheres. Suppose that Green simply >> has a very high percentage of "greenhouse gasses" -- including but >> not necessarily limited to CO2? And that Blue has a relatively low >> percentage thereof? Or put it in terms of albedo, and say that Blue's >> is higher than Green's, so that the same amount of incident solar >> raditation produces a higher degree of insolation. Will that not >> produce the -- relatively small; they're both "life zone" > planets! -- > difference in their average surface temperature? >> Frustrated, >> >> --Blattid > -- > http://www.urth.net/ To unsubscribe: send > "unsubscribe" to > urth-request at urth.net ---