When And How To Best Observe The Moon

Common sense may tell you that the best time to view the Moon is during a full moon, when the vastest area of it can be seen. Reality says instead that the correct time to observe is about six to nine days after the new moon. Rays from the sun hit the surface of the moon at a perpendicular angle during a full moon, which decreases the surface detail visibility. During the quarter and crescent phases, sunlight is hitting at a shallower angle, so details on the surface are much easier to see. The brightness of full moons can also produce an afterimage that lasts for several minutes in viewer’s eyes and washes out details from view. In the first week after a new moon, a smaller percentage of the moon can be seen, but the details will be much more pronounced. The best place to see these details are right along the “terminator,” or the dividing line between the illuminated side and the dark side of the moon.

The Moon is the only celestial body that can be easily viewed with the naked eye. The lunar seas, the basaltic plains, and other details like craters can all be seen without technological aid. Optical instruments can make the viewing experience more enjoyable though if available.

Binoculars are a good option for beginners. They offer a larger field of view, along with easier portability. One disadvantage is that binoculars are not as steady as other devices. However, binocular tripods are available, and the recent development of image-stabilized binoculars has also helped.

For the more interested observer, telescopes are the best option. A small telescope can usually show more detail than binoculars. Larger telescopes for amateur viewers can show details on the surface as small as 1 km in diameter. This is of course always dependent on atmospheric conditions. With a greater aperture of the telescopic mirror, or a larger lens, smaller features can be seen.

Filters can be used in order to bring out greater contrast. For example, a popular tool is a simple neutral density filter, which will cut down on the amount of light reaching the viewer’s eye by about 60-95%. With this filter, viewing does not need to be restricted to right after a new moon. Enough light can be filtered out to view a gibbous or even a full moon. There are no shadows during a full moon, so all that is seen are variations in the reflectivity of different parts of the Moon. The greatest difference in reflectivity is between the dark lunar seas and the light highlands because of the difference in the two compositions. The lunar seas are made of basaltic lava, which contain iron, titanium, and the darker metals. In contrast, the highlands are made of bright, aluminum-rich rock. With a filter, these different materials can be seen the best.

Daily Moon Horoscope
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