Fig. 34: Jupiter and its four largest moons. The moons can be observed in a different position every night.
Fig. 35: Saturn has the most extensive ring structure in our Solar System.
Fig. 36: The Pleiades is one of the most beautiful open clusters.
Jupiter (Fig. 34) is the largest planet in our solar system, with a diameter 11 times that of Earth. Jupiter appears as a disk with dark lines stretching across the surface. These lines are cloud bands in the atmosphere. Four of Jupiter’s 29 (and still counting!) moons (Io, Europa, Ganymede, and Callisto) can be seen as
Saturn (Fig. 35) is nine times the diameter of Earth and appears as a small, round disk with rings extending out from either side. In 1610, Galileo, the first person to observe Saturn through a telescope, did not understand that what he was seeing were rings. Instead, he believed that Saturn had “ears.” Saturn’s rings are composed of billions of ice particles. The major division in Saturn's rings, called the Cassini Division, is generally visible through all three ETX models. Titan, the largest of Saturn’s moons, can also be seen as a bright,
Deep-Sky Objects
You can use star charts to locate constellations, individual stars, and
Stars are large gaseous objects that are illuminated by nuclear fusion in their core. Because of their vast distances from our solar system, all stars appear as pinpoints of light, regardless of the size of the telescope used.
Nebulae are vast interstellar clouds of gas and dust where stars are formed. Most impressive of these is the Great Nebula in Orion (M42), a diffuse nebula that appears as a faint wispy gray cloud. M42 is 1600 light years from Earth.
Open Clusters are loose groupings of young stars, all recently formed from the same diffuse nebula. The Pleiades (Fig. 36) is an open cluster 410 light years from Earth. Several hundred stars of the cluster are visible through the your telescope.
Constellations are large, imaginary patterns of stars believed by ancient civilizations to be the celestial equivalent of objects, animals, people, or gods. These patterns are too large to be seen through a telescope. To learn the constellations, start with an easy grouping of stars, such as the Big Dipper in Ursa Major. Then use a star chart to explore across the sky.
Galaxies are large assemblies of stars, nebulae, and star clusters that are bound by gravity. The most common shape is spiral (such as our own Milky Way), but galaxies can also be elliptical, or even irregular blobs. The Andromeda Galaxy (M31) is the closest spiral- type galaxy to our own. This galaxy appears fuzzy and
TIPS FOR BEGINNERS 
Further Study....
This manual gives only the briefest introduction to astronomy. If you are interested in pursuing further studies in astronomy, a few topics are suggested below that are worth reading up on. Try looking up some of these in the optional Autostar glossary.
Also included below is a small sampling of books, magazines, and organizations that you might find helpful.
Topics
1.How is a star born? How does a solar system form?
2.How is the distance to a star measured? What is a light year? What is red shift and blue shift?
3.How are the craters on our Moon formed? How old is the Moon and Earth? How old is the Sun?
4.What is a black hole? A neutron star?
5.What are stars made of? Why are stars different colors? What is a white dwarf? A red giant? Have we ever seen the surface of a star besides our own sun?
6.What is a nova? A supernova?
7.What are comets? Minor planets? Meteors? Meteor showers? Where do they come from?
8.What is a planetary nebula? A globular cluster?
9.What is the Big Bang? Is the universe expanding or contracting, or does it always remain the same? What is dark matter?
10.What is an extrasolar planet? What is an accretion (or protoplanetary) disk?
11.What is the difference between an elliptical, a spiral, and an irregular galaxy?
Books
1.The Guide to Amateur Astronomy by Jack Newton and Philip Teece
2.The Sky: A User’s Guide by David Levy
3.Turn Left at Orion by Guy Consolmagno & Dan Davis
4.Astrophotography for the Amateur by Michael Covington
Magazines
1.Sky & Telescope
Box 9111, Belmont, MA 02178
2.Astronomy
Box 1612, Waukesha, WI 53187
Organizations:
1.Astronomical League Executive Secretary
5675 Real del Norte, Las Cruces, NM 88012
2.The Astronomical Society of the Pacific
390 Ashton Ave, San Francisco, CA 94112
3.The Planetary Society
65 North Catalina Ave, Pasadena, CA 91106
And watch Jack Horkheimer, Star Gazer, on your local PBS station.
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