Space exploration began with the launch of Sputnik and Astrophysics was born as the application of physics to the phenomena observed by Astronomy, which etymologically means laws of the stars.
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| Astronomy As A Hobby |
The first step in enjoying astronomy is to learn your way around the sky using only a dark sky, your eyes, and a star chart. Look for the more prominent patterns in the constellations and make note of the brighter stars. A star chart will give you a positional layout of the constellations, similar to a road map. You can then progress to using a pair of ordinary binoculars, and then to a telescope. A local astronomy society might allow you to use their telescope to view the night sky.
The further you are from city lights, the more objects you will be able to see in the night sky. You will be able to see thousand of stars, including the Milky Way, in very dark areas. Your latitude will also affect your view of the night sky. If you live in the northern hemisphere, you will not be able to see stars lying near the South Celestial Pole. The further north you are, the fewer stars you will be able to see south of the celestial equator. The time of year will also affect what you see, because as the Earth orbits the Sun, the night side looks out at different parts of the Universe. To get the best all-round view, choose a site as dark and as far away from trees and buildings as possible. Make sure you are warm, so you can stay out long enough for your eyes to adapt to the dark. It can take up to half an hour for your eyes to achieve maximum sensitivity in the dark. Use a red lightbulb, rather than an ordinary flashlight, to read your star chart to help retain your dark adaptation. To help orient yourself on your star charts, try to get an idea of where north is. Pick a prominent constellation or asterism on a chart and see if you can find it in the sky. You might be surprised to find that stars are quite far apart from each other in the sky; patterns that are easy to see on a star chart may be very spread out in reality and not so obvious. Some of the stellar patterns may also be changed by the fact that some of the fainter stars might not be visible. In a very dark sky, you may see many extra stars that interfere with stellar patterns. Once you find an obvious pattern, follow the chart and try to find another one. This is the first step in a technique called star-hopping. You can use the naked eye, binoculars or a telescope to star-hop. As magnification increases, the distances you star-hop will become smaller, and your star charts will become more detailed. Star charts do not show planets because planets are constantly moving. One way to distinguish a planet from a star is that planets hardly ever twinkle. They are not point sources of light, so the Earth’s atmosphere doesn’t affect their light as much as it affects starlight. A bright reddish “star†in the evening or morning twilight will be Mars. A brilliant “star†will be Jupiter. A fainter, yellower “star†will be Saturn. |