Basic astronomy, Appendix c – Meade Instruments 6" LS-6 ACF User Manual
Page 39

In the early 17th century Italian Scientist Galileo, using 
a crude telescope considerably smaller than the LS-6, 
turned it to look towards the sky instead of distant trees 
and mountains. What he saw, and what he realized 
about what he saw, forever changed the way mankind 
thought of 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 planets, 
stars, and galaxies. Building on his foundation, Henrietta 
Leavitt determined how to measure the distance to stars; 
Edwin Hubble proposed a glimpse into the origin of the 
universe; Albert Einstein unraveled the relationship 
of time and light. Almost daily, using sophisticated 
successors to Galileo’s crude telescope, such as the 
Hubble Space Telescope, more and more mysteries of 
the universe are being solved and understood. We are 
living in a golden age of astronomy. 
Unlike other sciences, astronomy welcomes 
contributions from amateurs. Much of the knowledge 
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 LS-6 telescope, keep 
Galileo in mind. To him, a telescope was not merely a 
machine made of glass and metal, but something far 
more - a window through which the beating heart of the 
universe might be observed. 
Objects in Space
Listed below are some of the many astronomical 
objects that can be seen with the LS-6
BASIC ASTRONOMY
APPENDIX C:
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. 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. 
Using the LS-6, brilliant detail can be observed on the 
Moon, including hundreds of lunar craters and maria, 
described below.
Craters are round meteor impact sites covering most 
of the Moon’s surface. With no atmosphere 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. 
BASIC
ASTRONOMY
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