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Ham the Chimp
Telescope Accessories
When you purchase a telescope -- any telescope -- what you get is…well…a telescope. You don't get anything else, and there are a few "accessories" that really shouldn't be considered accessories.
For example, you really, really need a mount for your telescope. Telescopes need to remain perfectly still while you are observing the heavens. Even the slightest movement isn't satisfactory. It is impossible to hold a telescope perfectly steady, so when you buy your telescope, you also need to buy a mount.
There are basically two types of telescope mounts to choose from: altazimuth and equatorial. The mount that will best serve your needs depends upon how and who will use it. There are two things that you need to remember no matter how much information you gather.
1. Astazimuth mounts cost less that equatorial mounts and they are easier to operate.
2. Equatorial mounts are more expensive than astazimuth mounts, are more difficult to operate, and have many more controls.
Slow-motion controls are another "extra," and both astazimuth and equatorial mounts can be fitted with them.
Filters are another "essential" accessory. For the beginner, just three filters will do; a solar, a lunar, and a light-pollution filter.
A solar filter will cost between $30 and $150 depending upon the filter you choose. Basically, a solar filter allows a user to observe the sun and sunspots because it allows only a small fraction of the sunlight to pass through it. Mylar filters (less expensive) cause the sun to appear as a light-blue color, while glass filters (more expensive) leave the sun in its natural yellow-orange color.
A lunar filter is not expensive, and if you want to observe the moon in any phase other than the first quarter, you need one. A lunar filter will cost about $20.
If you live in a metropolitan area, you most definitely need a pollution filter if you intend to look at deep sky objects. Pollution filters cost between $60 and $150, or even more.
See Also:
Astronomy For Kids - KidsAstronomy.com
Asteroids, Comets and Meteors
The Planet Mars
Earthlings have always been fascinated by the planet, Mars. The "little green men from Mars" invading Earth has been the stuff of science fiction for decades. On October 30, 1938, Orson Welles did a dramatization of H. G. Wells's "War of the Worlds" on the Mercury Theatre on the Air radio show. During the four commercial breaks of the program, there were disclaimers aired telling the audience that the content was fictional. Still, panic erupted in towns across America.
There was a new 40-inch telescope being built by the University of Chicago in 1895. An astronomy professor, Samual Leland Phelps, wrote a book about the project called "World Making." In the book, the professor wrote, "It will be possible to see cities on Mars, to detect navies in [its] harbors, and the smoke of great manufacturing cities and towns...Is Mars inhabited? There can be little doubt of it...conditions are all favorable for life, and life, too, of a high order. Is it possible to know this of a certainty? Certainly." Well…not exactly, professor!
From observations of Mars from stationary observatories on earth, astronomers concluded that:
1. The reddish color of Mars is caused by red rocks and dust.
2. The polar ice caps increase and decrease according to seasons.
3. There are what were thought to be canals on the surface. (That has since been disproved)
4. There are areas of Mars that change color. (It was believed that this was vegetation, but that has been disproved, as well.)
5. Mars has an atmosphere.
Space probes, beginning with Mariner 4, 6, 7, and 9 from 1965 through 1971, and the Viking 1 and 2 probes in 1976, disproved many of the previously held beliefs about Mars. We are learning more about Mars all the time, and one important fact is that there aren't any little green (or any other color) men living on Mars. |
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More articles:
Astronomy For Kids - KidsAstronomy.com
Constellation Energy Group
Space Tourism, Space Transport and Space Exploration News
Mercury Seven - Wikipedia, the free encyclopedia
Astrology - Wikipedia, the free encyclopedia
The Planet Jupiter
Sir Christopher Wren
Sir Christopher Wren once said, "In things to be seen at once, much variety makes confusion, another vice of beauty. In things that are not seen at once, and have no respect one to another, great variety is commendable, provided this variety transgress not the rules of optics and
geometry." For those of you who do not know, Christopher Wren was an English architect and mathematician who became Savilian Professor of Astronomy at Oxford in 1661. He is most famous for the buildings that he designed after the Great Fire of London.
Wren was interested in many things, and over his lifetime, he made many contributions to scientific knowledge and in many different ways. For example, he constructed a transparent beehive for the purpose of scientific observation; he studied the moon and experimented on terrestrial magnetism; and he also performed the first successful injection of a substance into a dog's bloodstream.
Along with Sir Paul Neile, Wren constructed a 35-foot telescope. During this timeframe, Wren also studied and improved the microscope and the telescope.
Wren was fascinated by the planet, Saturn. He began his observations of Saturn about 1652 with the intention of explaining the rings. Wren developed a hypothesis which he wrote in De Corpore Saturni. Before his work could be published however, Christian Huygens (a Dutch astronomer) presented his theory of the rings of Saturn. Wren immediately recognized the fact that Huygens' was a better hypothesis than his own, so De Corpore Saturni was never published.
Wren constructed a beautifully detailed model of the moon and gave it to the king. Although Sir Christopher Wren eventually turned his attention to architecture, he remained fascinated by astronomy all of his life.
Related Topics: The Planet Uranus,
Asteroids, Comets and Meteors, Our Sun's Twin
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