• Tonight - September 25, 2012 - see if you can make out the dark areas on the waxing gibbous moon. These smooth, low-lying lunar plains are called mare

(singular) or maria (plural), the Latin words for sea or seas. You should be able to see the darkened portions on the moon with the eye alone. But if you'd like to scrutinize the maria more closely with binoculars or the telescope, the view may be sharper before sunset or at dusk - or before the nighttime accentuates the lunar glare.
• In times past, astronomers really thought the dark areas contrasting with the light-colored, heavily-crated highlands were lunar seas. In some ways they were correct, except that these were seas of molten magma instead of water. Now solidified, this molten rock

came from volcanic eruptions that flooded the lunar lowlands. However, volcanic activity - at least from basaltic volcanoes - is now a thing of the moon's past.
• Everything you need to know: Harvest Moon 2012
• For the most part, lunar maria are found on the near side of the moon. In this respect, that makes the near side - not the far side - the dark side of the moon.
• Maria cover about 30% of the near side but only 2% of the far side. The reason for this is not well understood, but it has been suggested that the crust on the moon's far side is thicker, making it more difficult for magma to reach the surface.
• The lighter-colored highland regions of the moon are composed of anorthosite, a certain kind of igneous rock. On Earth, anorthosite is uncommon, except for in the Adirondack Mountains and the Canadian Shield. For this reason, people in this part

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