Sponge: List the five Moon phases. What are waxing and waning?

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Sponge List the five Moon phases. What are
waxing and waning?
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Ancient Astronomy
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The scientific method involves theory and
experimentation.
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Prior to the acceptance of the scientific method,
what scientists "thought" was accepted without
being tested.
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This held back the development of newer more
correct theories for centuries.
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Aristotle (384-322 B.C.) demonstrated one of the
earliest uses of the scientific method.He
noticed that all lunar eclipses showed a curved
shadow.
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He concluded that since the shadow was always
curved, then the Earth must be round. (A sphere
is the only object whose shadow is always
circular.)
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He also argued that distant stars would appear at
different positions to observers at different
locations on the Earth if the Earth were round.
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We use this difference in appearance to find the
distance to stars. The method is called
triangulation.
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PARALLAX - the apparent shift of an object as
seen from two different points of observation.
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Closer objects form a "fatter" imaginary
triangle.Farther objects form a "thinner"
imaginary triangle.
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The amount of parallax is inversely proportional
to an object's distance.
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COSMOLOGY - the study of the workings of the
universe on a large scale.
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The ancient Greeks believed the universe to be
comprised of the stars (which were attached to
the celestial sphere), and the known components
of the solar system the Sun, Earth, Moon, and
the five then known planets.
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The parts of the solar system were obviously not
part of the celestial sphere because they did not
move like the stars.
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They added additional spheres for the Sun and the
Moon.
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The Sun and Moon each move steadily and keep the
same brightness.
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Their location and appearance are easy to
predict.
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The explanation was not as easy for the other
members of the solar system.
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The planets Mercury, Venus, Mars, Jupiter, and
Saturn are not consistent in their movement and
brightness. The name "planet" means "wanderer".
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From night to night the planets generally move
from west to east (as does the Moon) this is
called direct motion.
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However, the planets seem to speed up and slow
down.
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Three of the planets Mars, Jupiter, and Saturn
loop back and move east to west for a few months
(retrograde motion).
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Also, Mars, Jupiter, and Saturn are brightest
during this retrograde motion.
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These observations did not fit the simple
cosmology offered by the ancient Greeks however,
few people questioned that this cosmology was
correct.
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THE GEOCENTRIC SOLAR SYSTEMAristotle (384-322
B.C.)
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The Earth must be stationary because1. The
Earth doesn't feel like it's moving.2. We feel
no strong wind from the motion.3. Why is there
no parallax visible in the position of the stars?
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The early models employed circles (the perfect
curve, what else would God use?).
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This cosmology was largely unchallenged until the
16th century.
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Circles around the Earth worked well for the Sun
and the Moon, but not for the planets.
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For the planets, they added the epicycle to the
deferent.
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The best geocentric model of all time was
constructed by the Greek astronomer Ptolemy
around 140 A.D.
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It was made of approximately 80 different circles.
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The Ptolemaic cosmology was the accepted system
for over 1000 years.
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Aristarchus (310-230 B.C.) was one Greek who
did question what was accepted by most others.
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He suggested that a rotating Earth which orbited
the Sun would explain the observations.
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But Aristotle's influence was too great and his
ideas persisted.
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ANCIENT ASTRONOMYAncient astronomy was
practical in nature.Sailors and farmers.
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Ancient astronomical sitesStonehenge (England)
- construction spanned 2000 years from 2800 B.C.
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Carucol Temple (Mexico) - built by the Mayans
around 1000 A.D.
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Big Horn Medicine Wheel (Wyoming) built by the
Plains Indians.
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Other cultures have great astronomical
traditions the Chinese and the Arabs are
prominent figures.
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