It might be that all the planets flop around unless they have a large moon to provide stability.
In the shadow of the Moon
New Scientist | 30 January 1999 | editors
Posted on 08/31/2004 8:42:25 AM PDT by SunkenCiv
http://www.freerepublic.com/focus/f-chat/1203912/posts
18 posted on 08/31/2004 12:24:41 PM PDT by RightWhale
http://www.freerepublic.com/focus/f-chat/1203912/posts?page=18#18
New evidence for the Moon's soft middle
New Scientist | 14 February 2002 | Will Knight
Posted on 12/27/2004 2:29:35 PM PST by SunkenCiv
http://www.freerepublic.com/focus/f-chat/1309193/posts
28 posted on 12/31/2004 9:21:42 AM PST by SunkenCiv
http://www.freerepublic.com/focus/f-chat/1309193/posts?page=28#28
When the Days Were Shorter
Alaska Science Forum (Article #742) | November 11, 1985 | Larry Gedney
Posted on 10/04/2004 10:31:59 AM PDT by SunkenCiv
http://www.freerepublic.com/focus/f-chat/1234919/posts