Basic Astronomy - Meade DS-2000 Instruction Manual

BASIC ASTRONOMY

In the early 17th century Italian Scientist Galileo, using a telescope smaller than your DS-2000
model, turned it skyward instead of looking at the distant trees and mountains. What he saw,
and what he realized about what he saw, has forever changed the way mankind thinks about
the universe. Imagine what it must have been like being the first human to see moons revolve
around the planet Jupiter or to see the changing phases of Venus! Because of his observations,
Galileo correctly realized Earth's movement and position around the Sun, and in doing so, gave
birth to modern astronomy. Yet Galileo's telescope was so crude, he could not clearly make out
the rings of Saturn.
Galileo's discoveries laid the foundation for understanding the motion and nature of the plan-
ets, stars, and galaxies. Building on his foundation, Henrietta Leavitt determined how to meas-
ure the distance to stars, Edwin Hubble gave us a glimpse into the possible origin of the uni-
verse, Albert Einstein unraveled the crucial relationship of time and light, and 21st-century
astronomers are currently discovering planets around stars outside our solar system. Almost
daily, using sophisticated successors to Galileo's telescope, such as the Hubble Space
Telescope and the Chandra X-Ray Telescope, more and more mysteries of the universe are
being probed and understood. We are living in the golden age of astronomy.
Unlike other sciences, astronomy welcomes contributions from amateurs. Much of the knowl-
edge we have on subjects such as comets, meteor showers, variable stars, the Moon, and our
solar system comes from observations made by amateur astronomers. So as you look through
your Meade DS-2000 telescope, keep in mind Galileo. To him, a telescope was not merely a
machine made of glass and metal, but something far more—a window through which the beat-
ing heart of the universe might be observed.
Autostar Glossary
Be sure to make use of Autostar's Glossary feature. The Glossary menu provides an alpha-
betical listing of definitions and descriptions of common astronomical terms. Access directly
through the Glossary menu or through hypertext words embedded in Autostar. See "GLOS-
SARY MENU," page 25, for more information.
Objects in Space
Listed below are some of the many astronomical objects that can be seen with the DS-2000
Series Telescope:
The Moon
The Moon is, on average, a distance of 239,000 miles (380,000km) from Earth and is best
observed during its crescent or half phase when Sunlight strikes the Moon's surface at an
angle. It casts shadows and adds a sense of depth to the view (Fig. 34). No shadows are seen
during a full Moon, causing the overly bright Moon to appear flat and rather uninteresting
through the telescope. Be sure to use a neutral Moon filter when observing the Moon. Not only
does it protect your eyes from the bright glare of the Moon, but it also helps enhance contrast,
providing a more dramatic image.
Brilliant detail can be observed on the Moon, including hundreds of lunar craters and maria,
described below.
Fig. 34: The Moon.
Note the deep shad-
Craters are round meteor impact sites covering most of the Moon's surface. With no atmos-
ows in the craters.
phere on the Moon, no weather conditions exist, so the only erosive force is meteor strikes.
Under these conditions, lunar craters can last for millions of years.
Maria (plural for mare) are smooth, dark areas scattered across the lunar surface. These dark
areas are large ancient impact basins that were filled with lava from the interior of the Moon by
the depth and force of a meteor or comet impact.
Twelve Apollo astronauts left their bootprints on the Moon in the late 1960's and early 1970's.
However, no telescope on Earth is able to see these footprints or any other artifacts. In fact, the
smallest lunar features that may be seen with the largest telescope on Earth are about one-half
mile across.
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