The Moon is positioned near a new moon phase about every 29 days. At that time, we see only a thin crescent of the illuminated surface. Most of its face toward Earth is in shadow. The view below of the Moon’s orbit is oblique, not from directly overhead. The size of the Moon’s orbit is scaled 50x larger than actual size. A 30 sec animated version is at this link.
I enjoy the challenge to see the thinnest crescent sliver of the Moon possible. During the final days of the cycle, as the Moon wanes, I check the southeast sky in the morning before sunrise. The Moon’s crescent appears thinner each day. If my luck is good, the morning sky is clear and seeing is excellent the day before the Moon disappears into the glare of the Sun. Sometimes there is another object nearby such as Venus or Mars. The pairings of two or three objects often make for beautiful photographs. On those occasions, I set the camera on a tripod in front of the house. Hand-held exposures never work.
For the photographers, my settings are often ISO of 160-200, white balance of tungsten or incandescent bulb, f/2.8, shutter speed of one half up to 2 seconds depending on the brightness of the Moon. Manual focus is needed. The camera has a hard time on auto focus. Try a range of settings to find out how your camera performs best.
One of my first attempts was in 2005 when the Moon and Mercury were close. I played around with with photo editing software to add some effects. One of the aspects of these photographs is the visible Earthshine upon the Moon. It faintly shows in the image above. How does Earthshine come about? Why does it happen? Below is a view of the Moon and Earth drawn to scale both in size and distance apart. The view was rendered on my desktop planetarium software. Assume the Sun is far to the left in this view. When the Moon is near new, sunlight travels to the Earth with some small amount reflected back toward the Moon. It is often just enough to illuminate the shadowed side of the Moon if the rest of the sky is darker. Here are more Earthshine photographs. For me, they give a sense of depth to the Moon. They are some of my favorite scenes in the sky. I hope you enjoy them, too. Thanks for joining me.