Astro Bob blog: Liquid eye meets rocky moonWe continue with our exploration of the moon with binoculars and small telescopes.
By: Bob King, Duluth News Tribune
Liquid eye meets barren moon
Last night's moon photographed through a small telescope.
Sunlight comes in a at low angle along the day-night boundary
(terminator) casting long shadows that enhance the outlines of craters
and other landscape features. Photo: Bob King
I stopped during a walk in the woods yesterday and looked around at the small balsam firs standing in snow littered with bits of bark, pine cone scales and broken evergreen needles. This is where I belong, I thought. Somehow a kid from Chicago found his favorite place on Earth, and it turned out to be in the middle of a scrubby forest atop volcanic bedrock. I'm not sure how we become more comfortable in one landscape over another but I'm glad for it. Perhaps you have a special corner of Earth you call home. If so, I hope you're living there now.
What a nice surprise the clear sky was last night. I spent at least an hour looking at the moon in the scope. All sorts of delicacies were on the table from thread-like faults to ancient, colorful lava flows to watching the first rays of sunlight touch the pinnacle of a mountain peak inside a shadow-filled crater. If northern Minnesota is my primary home, the moon is my second. Because it's so close to Earth, a vast amount of detail is visible even in a small telescope. If I had no need for sleep, I'd spend the whole night looking at the moon. Soft, moist eye meets dry, sun-beaten rock. What wonders we're permitted to enjoy in a lifetime.
Three mountain ranges come into view tonight near the terminator in moon's northern hemisphere (top half). Photo: Bob King
Tonight the moon's terminator scootches further to the east; what was in shadow last night emerges now into sunlight. Highlights this evening include a great profusion of craters large and small in the vicinity of the terminator. Some of these as well as three of the moon's 18 mountain ranges -- the Apennines, Alps and Caucasus -- are visible in binoculars. The Apennines are a gently curving range about 400 miles long with peaks as high as three miles. Their tops will be lit in the early morning lunar sun. Can you also see the other two ranges in binoculars? Give it a try tonight.
Mountains on Earth generally form as a result of moving tectonic plates that "bump" into one another. On the moon, many of the most prominent mountain chains like the Apennines were formed from rock uplifted during enormous impacts long ago. One of the largest dark spots that forms part of the "man in the moon's" face is Mare Imbrium or the Sea of Rains. This 700-mile diameter basin was formed formed by a colossal asteroid impact about 3.7 billion years ago which later filled up with lava. Several mountain ranges define its perimeter including the Apennines.
Were you out this morning to see the shuttle Endeavour and space station cross through the sky? I went out not knowing how far apart in time they'd be. Endeavour came first and passed right next to Saturn as it traveled from the southwest to the southeast. But where was the space station? Ah! Two minutes later the considerably brighter station followed virtually the same path.
We might have another chance to see them tomorrow morning if the weather is bad at the landing sites. For Duluth and region, take a look in the southeastern sky at 5:06 a.m. for the shuttle followed by the space station at 5:10 a.m.
Both Endeavour and the ISS flew right past Saturn during dawn this morning. Since their paths are not identical they must have been in slightly different orbits, one higher and the other lower. Details: 35mm lens at f/2.8, 25-second exposure at ISO 200. Photo: Bob King