Doug... wrote:
In article ,
says...

Doug... wrote:


What's making a really significant difference is that... it's also moving away from
periapsis and towards apoapsis. Since Mars' orbital eccentricity is
currently *much* greater than Earth's, that means that the change in the
solar energy reaching the ground on Mars between periapsis and apoapsis
is *far* greater.

Doug,

With 1.52 semimajor axis and .093 eccentricity,
I'm getting 1.37 AU perihelion and 1.66 AU apohelion.

1.37/1.66 = .83

.83^2 = .69

I believe you are correct that Mars' greater eccentricity
makes a substantial difference between periapsis and apoapsis
insolation.


According to a very well-done book I've been poring over, "Mars, The
Mystery Unfolds" by Peter Cattermole, the difference between perihelion
and apohelion insolation is on the order of 40%. That's QUITE a
difference.

Doug



1/.69 is about 1.45 so my figures can land in the same ball park.

The percentage varies depending on whether you're considering

(apohelion insolation/perihelion insolation)
or
(perihelion insolation/apohelion insolation)

Hop David
http://clowder.net/hop/index.html