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The Stars
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:
O'Reilly Media | Digital Astrophotography
Our Solar System
The Zodiac
The zodiac is a cycle that covers a year's time. There are several versions of the zodiac system. There is a Babylonian zodiac, an Indian zodiac, a Chinese zodiac, a Western zodiac, and several others. All of the various zodiacs are basically the same. They are all based upon the constellations and they all contain 12 stations, or signs.
The Western zodiac is the one that is mostly used in the United States. Modern Western astrological signs are really just simplifications of the signs used in Hellenistic times.
In the list below are the Roman names for the signs of the zodiac, their ecliptic longitudes of their first points, the symbols that represent them, and the associated dates:
Aries: 0°, the Ram, March 21 to April 20
Taurus: 30°, the Bull, April 20 to May 21
Gemini: 60°, the Twins, May 21 to June 21
Cancer: 90°, the Crab, June 22 to July 22
Leo: 120°, the Lion, July 23 to August 22
Virgo: 150°, the Virgin, August 23 to September 22
Libra: 180°, the Scales, September 23 to October 23
Scorpio: 210°, the Scorpion, October 24 to November 22
Sagittarius: 240°, the Archer, November 22 to December 21
Capricorn: 270°, the Sea-goat, December 22 to January 19
Aquarius: 300°, the Water Carrier, January 20 to February 18
Pisces: 330°, the Fish, February 19 to March 20
Sidereal zodiac astrology (used mostly by Indian astrologists) dates are different from the tropical zodiac astrology dates. However, the tropical zodiac dates are the ones that are used primarily in the West.
Astrology is not an exact science (if you think of it as a science). All of the implications of certain signs and the position of certain planets are open to interpretation. Different astrologists will give different readings based upon the same information.
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More articles:
Ham the Chimp - Wikipedia, the free encyclopedia
Amateur Astronomy Magazine
Telescopes.com: Shop Telescopes and Telescope Eyepieces
The Planet Venus
SOLAR ECLIPSE: Stories From the Path of Totality
Astronomy Clubs
Planting by the Moon
Ah, the moon! The moon has been studied by astronomers (both professional and amateur) for centuries. We even reached out and touched it when Neil Armstrong stepped onto the moon 1969. The moon has been the subject of songs, movies, and poetry, and probably always will be. Astronomers have always been utterly fascinated by the moon, and mankind has been fascinated by how it affects the earth and earthlings since time began.
We do know without a doubt that the moon regulates the ocean tides. It is also a certainty that sleeping with moonlight on your head will not turn you into a werewolf or drive you insane. Some beliefs about the moon have been proven true while others have been proven not true.
Farmers have planted according to the moon for centuries, and more and more farmers are returning to those moon-planting axioms every year. Why? Because they work. Planting root vegetables when the moon is "waning" will produce more root vegetables like potatoes, carrots, turnips, beets, etc. Planting vegetables when the moon is increasing will produce more vegetables that produce above ground (beans, peas, lettuce, tomatoes, etc.).
Planting and gardening by the moon gets even more specific. For example, it is better to turn soil when the moon is in the last quarter. The moon tells farmers and gardeners when it is to their advantage to plant, as well as when it is to their advantage to pull weeds or turn soil.
There are many who doubt the validity of planting by the moon, but consider that the moon does have an effect on humans (you can get a lot of debate about that statement). We don't fully understand everything we know about those effects yet. You can ask any policeman, clergyman, doctor, or nurse and they will tell you that during a full moon, there are more crimes committed, more suicides, and more babies born.
Related Topics: The Planet Neptune,
The Constellations, Ancient Astronomical Calendars
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