Only one more day left until Christmas Eve, and astronomers have just discovered a unique feature on the lunar surface. Although accepted for many years to be a natural feature of selenography, modern astrophotography coupled with today’s high-powered telescopes have discovered an area near the lunar North Pole that’s apparently being used as a runway by a man in a red suit piloting an unusual spacecraft…
Be sure to spark the imaginations in your young viewers (or simply enjoy the holiday smile) as you show them the Alpine Valley!
Tonight’s outstanding feature will be the lunar Vallis Alpes. Located near the terminator in the lunar “North Pole”, this wonderful gash in the landscape very conspicuously cuts across the lunar Alps just west of crater Aristotle. As you view this 180 km long and (at points) less than 1 km wide feature, ask yourself how it was formed. While it looks very artificial with limited aperture and possibly like it could have been formed by a glancing blow from a small asteroid, it’s actually a volcanic/tectonic feature called a sinuous rille.
If Santa were to look up along the southeast side of the Alpine Valley, he’d see a very tall linear cliff that’s slightly concave – like an amphitheater. To the northwest would be a small series of hills leading up the the grand lunar Alps. To the south would be another curved mountain ring about 16 or 17 miles in length, and from 3 to 4 miles in width. This forms the gorge, bordered on the east by sheer vertical cliffs, towering thousands of feet above the bottom of the valley. The valley floor is a flat, lava-flooded surface that is divided by a slender, cleft-like rille. Chances are this “little runway” was once a graben that which was flooded with magma.
But tonight? It’s the most special place not on Earth!