|
Our Sun
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:
Christopher Wren - Wikipedia, the free encyclopedia
The Planet Neptune
The Planet Saturn
The planet Saturn resembles the planet Jupiter in many ways. Saturn is also a planet that has very little if any solid matter. It is believed that there is a hard rocky core, but that belief is unproven (albeit very probable) theory. Saturn, like Jupiter, is made up of gases and liquids. There is an internal heat source. We know this because Saturn radiates more energy than it receives.
Saturn rotates fast. It makes one complete revolution once every 10 or 11 hours. Saturn rotates around the sun once every 29.5 years. Because it rotates so fast, Saturn is flattened at the poles, making it an almost oblate planet.
The space probes, Pioneer 11, Mariner 11 and 12, and Voyager I and II, provide the best and most accurate information to astronomers about the planet Saturn, even though the Hubble space telescope takes very good images of Saturn. The space probes get "up close and personal," so to speak, and have provided information about Saturn that nothing else could have provided.
Wind velocity on Saturn is extreme. Wind speeds of more than 1,118 mph have been recorded. Unlike the winds on Jupiter, however, wind speeds on Saturn do not seem to be closely related to the positions of the belts and bands.
The rings around Saturn are one of the most interesting features. Really high-resolution pictures taken on the Voyager missions tell us that the rings are actually made up of hundreds of thousands of very small rings. The evidence suggests that the rings are composed of particles that are mostly ice crystals. A lot has been learned about the rings of Saturn over the last 20 or so years, but there is so much about them that is still a mystery. |
|
More articles:
NASA - Home
Solar System Exploration: Planets: Jupiter
Physics/ Astronomy Assistant Professor | Los Rios Community ...
Solar System - Wikipedia, the free encyclopedia
Basic Astronomy - General Astronomy Quiz
Mirrors and Lenses
NASA
In 1958, the Congress of the United States enacted, and the President Dwight D. Eisenhower signed, the National Aeronautics and Space Administration Act (NASA). The act begins with a very simple statement; "An Act to provide for research into the problems of flight within and outside the Earth's atmosphere, and for other purposes."
The Cold War between the United States and (what was) the Soviet Union was in full swing. With the passing and signing of the act that established NASA, what has come to be known as the "space race" was kicked off. The Soviet Union had launched Sputnik 1 and had an apparent head start in the race to space.
The United States caught up quickly. In January 1958, Explorer 1 (America's first earth satellite) was launched.
Then NASA launched human space flight initiatives with Mercury's single astronaut program (flights during 1961-1963) to determine if a human could survive in space.
The Project Gemini (flights during 1965-1966) with two astronauts to was used to practice space operations, like rendezvousing and docking spacecraft and extravehicular activity (EVA or space walks).
This was followed with Project Apollo (flights during 1968-1972) to explore the Moon. Since then NASA has conducted robotic missions to the Moon (Ranger, Surveyor, and Lunar Orbiter); Venus (Pioneer Venus), Mars (Mariner 4, Viking 1 and 2), and the outer planets (Pioneer 10 and 11, Voyager 1 and 2).
NASA has had its problems over the years. The space shuttle Challenger blew up on January 28, 1986, killing seven astronauts. The space program was grounded for two years. Another tragedy happened on February 1, 2003, when the space shuttle Columbia disintegrated on re-entry. All seven people on board were killed instantly.
Space travel is not without its dangers, but space in the next great frontier for mankind to conquer. You can be sure that the space program and NASA will continue into the foreseeable future.
Related Topics: Telescope Accessories,
Astronomy Funny Bone, Guide to Buying a Telescope
|