Many amateurs complain about the Moon's overwhelming glare, especially during the gibbous and full phases. Although it will not damage your eyes, the Moon's brightness can be diminished by using a neutral-density Moon filter or by placing a stop-down mask in front of your telescope.
Stopping down a telescope to about 2 or 3 inches in aperture will make moonlight more manageable. Cut a circular piece of cardboard matching the diameter of your telescope's objective lens or primary mirror, and then cut out a hole 2 or 3 inches across. Secure the mask in front of the telescope, and you're set. If you have a reflector or catadioptric telescope, be sure to offset the hole to one side so that no part of the secondary-mirror support blocks the mask's opening.With a detailed Moon map in hand, you can survey our nearest space neighbor in amazing detail.
Antonin Rukl's Atlas of the Moon
is the best lunar atlas in print, while Patrick Chevalley and Christian Legrand's freeware Virtual Moon Atlas
is a great program for creating customized charts.
Each lunar phase holds something exciting for the sightseeing astronomer. The crescent phases after New Moon through First Quarter display a tremendous variety of lunar terrain. Dominating the equatorial zone are the vast expanses of the lunar seas Maria Crisium, Fecunditatis, Tranquilitatis, and Serenitatis. Many large craters are scattered to their north, while the South Polar Region is awe-inspiring in its coarse beauty. Of special interest there are the craters Clavius and Tycho, both of which see sunrise the night after First Quarter.
After First Quarter, sunlight slowly pours into Oceanus Procellarum. The largest of all lunar maria, the Ocean of Storms holds many wondrous sights, including the craters Copernicus and Kepler. To the north, the crater remnant Sinus Iridum and the unusual dark-floored crater Plato receive first light. To the south, Tycho seems ablaze as its magnificent system of bright rays scatters beyond the Moon's equator. Once Full Moon passes, the sequence reverses, with shadowing and lighting effects adding a different perspective to our neighbor.
As the Moon tracks across the sky, it will often pass in front of, or occult, stars. On rare occasions, it will occult a planet. Watching the Moon slowly cross in front of another celestial object can be a lot of fun, as well as a useful scientific activity.
By knowing the exact moment of disappearance or reappearance of a star or planet, scientists may detect slight fluctuations in the Moon's orbital distance and speed. It is also possible to determine if the occulted star is single or an unresolved double.Occultations of brighter stars and planets are always fun to watch.
Find a year's worth of upcoming occultations published in the Royal Astronomical Society of Canada's annual Observer's Handbook
. Lunar eclipses are also great to watch from any location. All you need is a good view of the Moon. Information and tips about upcoming eclipses are also available in Astronomy
as well as in my book Eclipse!
(John Wiley & Sons, 1997).Related video: Observe the Moon with a small telescope
— Follow a few easy tips, and you'll be an experienced moonwatcher in no time.