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Old 02-05-2007, 02:48 PM
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erick (Eric)
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Join Date: Dec 2006
Location: Gerringong
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<reopen random off topic chatter>

So how come we got the prettier face of the Moon facing the Earth - who arranged that? Seriously, why so few maria on the far side?

OK, I did a bit of Wikipedia searching:-

"The two hemispheres have distinctly different appearances, with the near side covered in multiple, large maria (Latin for 'seas,' since the earliest astronomers thought, wrongly, that these plains were seas of lunar water). The far side has a battered, densely cratered appearance with few maria. Only 2.5% of the surface of the far side is covered by maria,[1] compared to 31.2% on the near side. The most likely explanation for this difference is related to a higher concentration of heat-producing elements on the near-side hemisphere, as has been demonstrated by geochemical maps obtained from the Lunar Prospector gamma-ray spectrometer. While other factors such as surface elevation and crustal thickness could also affect where basalts erupt, these do not explain why the farside South Pole-Aitken basin (which contains the lowest elevations of the Moon and possesses a thin crust) was not as volcanically active as Oceanus Procellarum on the near side (for a more detailed discussion, see Lunar mare)."

So, there it is - we don't really know - that doesn't surprise me.

</end random off topic chatter>
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