[meteorite-list] Venus May Have Once Had A Moon

[Philip R. Burns]

At 04:12 PM 10/11/2006, Philip R. Burns wrote:
>At 02:57 PM 10/11/2006, Rob McCafferty wrote:
>
>>If log angular momentum is plotted vs log Mass, all
>>planets fit nicely on a line except Venus and Mercury
>>(Earth/moon system needs to be combined).
>>Now since angular momentum is a conserved quantity, it
>>matters not one jot how far a planet and its moon
>>drift apart. Combine the angular momentum of Venus and
>>Mercury and they slot nicely on the line like all the
>>others.
>>If some accuse me of favouring an idea which is too
>>neat, I'd accuse the author of this article of this
>>article of over-thinking a problem. The peculiar
>>rotation of venus is rather nicely explained by it
>>losing a moon, especially one as big as Mercury.
>
>I believe the late Robert Harrington (d. 1993) of the U. S. Naval 
>Observatory proposed many years ago that Mercury was an escaped moon 
>of Venus.  I don't have the reference to hand, but it shouldn't be 
>too hard to find.

Here is the reference:

T.C. Van Flandern and R.S. Harrington (1976), "A dynamical 
investigation of the conjecture that Mercury is an escaped satellite 
of Venus", _Icarus_ vol. 28, pp. 435-440.


-- Philip R. "Pib" Burns
    pib at pibburns.com
    http://www.pibburns.com/