Lunar Observing Tips

Last Saturday was International Observe the Moon Night.  An opportunity for observers around the world to observe the moon, learn about its features and share some experiences.  Usually local astronomy clubs set up a variety of telescopes to give an "up close and personal" view of Earth's only natural satellite. 

International Observe the Moon Night is usually held in October, on a weekend close to the first quarter phase.  First Quarter is actually the best time to observe the moon for several reasons.

First, it rises about noon and so is easily visible in the evening for several hours after sunset. It is also highest above the horizon after sunset which means there is less atmosphere to gaze through, and therefore less distortion. Third quarter moon is similar in how it reflects light, but it doesn't rise until well after midnight.

Second, when the moon is at First Quarter, the light from the sun is not striking the surface directly but rather at a low angle.  This causes the the mountains and craters to stand out in sharp relief, showing off their height and depth.  At full moon phase the lunar features look flat, sort of like looking at a bright light reflected off a dinner plate.  

Using a telescope is great for observing the lunar features, but it's best not to use too much in the way of magnification.  While the moon will look like it's "right there" it will also zoom out of the field of view pretty quickly, requiring more adjustments.  Lower magnification lets you see the entire disk of the moon and therefore enjoy more of the whole experience.

First quarter moon is best for observing its features.
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