Today!

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Today! From Earths Perspective Lunar
Motion A Brief History of Astronomy
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FROM NOTES Lunar motion tidally
locked--gravity makes same side (with a
displaced core) always face earth. Synodic
period--29.5 days --cycle of phases.
--Length of day on the moon. --Lunar
phases--see diagrams. Siderial
period--27.3 days --with respect to
stars.
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The Moon was hit by a large object, making
oval-shaped, and front side is closer to iron
core than back. This keeps it tidally locked with
same side facing Earth.
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The Phases of the moon.
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A Brief Early History of Astronomy (From
NOTES) 5,000 BC--Sumerians--astrology and '12th
planet'? 2,500 (or 8,500) BC--sphinx and great
pyramid. 1,600 BC--Babylonians--star and planet
tables. 1,500 BC (or much earlier)Hindus
--cycles of cosmos and lifetime of sun. 500
BC--Pythagoras--earth and heavens spherical. 350
BC--Aristotle--physics of forces, geocentric
universe. 250 BC--Aristarchus--first sun-centered
system. 200 BC--Erastosthenes--accurate size of
earth. 130 BC--Hipparchus--epicycle, precession,
charts. 7 AD?--Wise men tracked the Christmas
star --Saturn conjunct Jupiter? 125
AD--Claudius Ptolemy--accurate geocentric
model. 400 AD Hypatia and the Fall of the
Alexandrian Library
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5,000 BC--Sumerians wrote of astrology and
'12th planet with godlike inhabitants?
Nibiru?
Zecharia Sitchin
His book.
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2,500 (or 8,500?) BC--Sphinx and Great
Pyramid. Harvard research found water markings on
Sphinx, dating it to prior to 8500 BC
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1,600 BC--Babylonians--star and planet tables.
The Babylonian zodiac was sidereal, i.e.
longitudes were not measured from the vernal
equinox (the intersection with the celestial
equator), but from a small number of bright fixed
stars near the ecliptic. The most important
reference stars appear to have been Aldebaran
(defining 15º Taurus), Pollux (0º Cancer),
Regulus (5º Leo), Spica (0º Libra), Antares
(15º Scorpius) and Deneb Algedi (0º Aquarius).
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1,500 BC (or much earlier)Hindus --cycles of
cosmos and lifetime of sun.
Hindu Cycle Ancient Modern
yuga 24,000 yrs 25,800 yrs, precession
manvantara 308 mill. yrs 225 mill.yrs., galactic year
Lifetime of sun 8.6 bill. yrs 8.8 bill. yrs., using nuclear physics
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500 BC--Pythagorasthe earth and heavens are
spherical. Hence the music of the spheres, he
called it.
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350 BC--Aristotle--physics of forces,
geocentric, or Earth-centered universe. Planets
on spheres. Each one has several, some going
backward to account for retrograde motion.
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First sun-centered system.
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200 BC--Erastosthenes--accurate size of
earth determined by the angle of Suns rays at
noon.
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130 BC--Hipparchusepicycle designed for
retrograde motion, precession of equinoxes
discovered, charts of planet motion.
Mr. Observer!
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7 AD?--Wise men tracked the Christmas star --was
it Saturn conjunct Jupiter?
Painting by Giotto Christmas star as Halleys
comet?
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125 AD--Claudius Ptolemy--accurate geocentric
model of universe
Epicycle upon epicycleits defects were its
complexity and different handling of inner
planets from outer.
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400 AD Hypatia and the Fall of the Alexandrian
Library
Poor girl. She was head of the Alexandrian
Library, and Christian fanatics cut off her
limbs and head, and dragged her dead body
behind her chariot through the streets of
Alexandria. After all, she didnt believe the
Earth was the center of the Universe! Then they
burned down the Library, destroying about ½ the
knowledge of the ancient world.