Celestron Omni CG-4 Telescope Mount Celestial Observing - Page 1

Celestial Observing English What can you see with your telescope? This section covers visual observing hints for solar system and deep sky objects as well as general observing conditions which will affect your ability to observe. The larger the aperture of your telescope, the easier it is to locate and observe objects. Many amateurs use the phrase "there is no substitute for aperture" which is true, but many newcomers and especially young people begin with small aperture telescopes, and as their interest levels grow, so can their aperture requirements. Observing the Moon Often, it is tempting to look at the Moon when it is full. At this time, the face we see is fully illuminated, and its light can be overpowering. In addition, little or no contrast can be seen during this phase. One of the best times to observe the Moon is during its partial phases (around the time of first or third quarter). Long shadows reveal a great amount of detail on the lunar surface. At low power, you will be able to see most of the lunar disk at one time. Change to optional eyepieces for higher power (magnification) to focus in on a smaller area. Lunar Observing Hints To increase contrast and bring out detail on the lunar surface, use optional eyepiece filters. A yellow filter works well at improving contrast while a neutral density or polarizing filter will reduce overall surface brightness and glare. Observing the Planets Other fascinating targets include the five naked eye planets - keep in mind that the larger the aperture of your telescope, the more detail you can see on the planets. You can see Venus go through its lunar-like phases. Mars can reveal a host of surface detail and one, if not both, of its polar caps. You will be able to see the cloud belts of Jupiter and the great Red Spot (if it is visible at the time you are observing). In addition, you will also be able to see the moons of Jupiter as they orbit the giant planet. Saturn, with its beautiful rings, is easily visible at moderate power. A planisphere or star charts for the current time and date, will help you locate what planets are visible and where. Planetary Observing Hints • Remember that atmospheric conditions are usually the limiting factor on how much planetary detail will be visible. So, avoid observing the planets when they are low on the horizon, or when they are directly over a source of radiating heat, such as a rooftop or chimney. See the "Seeing Conditions" section later in this manual. • To increase contrast and bring out detail on the planetary surface, try using eyepiece filters. 1