Transcript Biography

Early Astronomers
Intro to Astronomy Unit
Ancient Greeks
Biography
 Aristotle (384-322 BC)
Major Contributions
 Proved that the Earth
is round using math
and observations.
Claudius Ptolemy
Biography
 Greek
 Lived ca. AD 83-168
Major Contributions
 Created the Geocentric
model of the solar system in
which the Earth was the
center.
Nicolaus Copernicus
Biography
 1473-1543
 From Poland
Major Contributions
 Earth as a planet
 Model of the solar system
with the sun at center called
the Heliocentric model.
 Proved that Earth rotates
Johannes Kepler
Major Contributions
Biography
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Discovered 3 laws of planetary
motion:
 1571-1630
1) Planet’s orbit is an ellipse (oval)
 Danish
shape
 Brahe’s assistant
2) The planets move faster when
nearer the sun and slower when
 Mathematical
farther away
 *New astronomy*
3) A planet’s orbital distance
determines its distance from the
sun
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Defined the term astronomical unit
as the average distance between
the Earth and the sun
(approximately 150 million km)
Galileo Galilei
Biography
 1564-1642
 Italian
Major Contributions
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Galileo used a telescope to
make better observations.
1. Four “satellites” or moons
orbiting Jupiter
2. Planets are circular disks,
not just points of light
3. Venus has phases just
like the moon
Sir Isaac Newton
Biography
 1642-1727
 English
Major Contributions
 Formulated the law of
universal gravitation saying
that all objects have gravity
between them.
 Explained the laws of inertia
and gravity.
 Inertia says that an object in
motion will stay in motion till
acted on by another force.
Contemporary Astronomers
Edwin Hubble
Major Contributions
Biography
 Explained that the universe
 Born: 11/20/1889
was and still is expanding
 Died: 9/28/1953
 Has a telescope that orbits in
space named after him. The
 American
Hubble Space Telescope
Stephen Hawking
Biography
 Born:1/8/1942
 British
Major Contributions
 Theorized the existence of
black holes.
Geocentric Model/Earth Centered
Heliocentric Model/ Sun Centered
Geo and Heliocentric
Geocentric meaning Earth Centered was
created by Claudiaus Ptolemy. He thought
the earth was the center of everything in
the Solar system.
 Heliocentric meaning Sun Centered was
created by Nick Copernicus and he
thought and proved that the sun was the
center of the solar system and every thing
revolves around the sun.
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Astronomical Unit
The time it takes for light to travel from
the sun to earth is 1 AU. ABOUT 150
MILLION KILOMETERS…….
 Light Year- The distance light travels in
1 year
 Light Minute- The distance light can
travel in 1 minute
 Light Hour- The distance light can
travel in 1 hour.
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The Big Bang Theory
 Big
Bang Theory is where a
nebula cloud of rotating gases
and rock; condensed, heated
then cooled and collapsed. As
a result this created our galaxy
and solar system.
Order of Formation
Big Bang
1. Galaxies
2. Solar system
3. Sun
4. Earth
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Big Bang Order of Formation
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As this cloud of gases and rock condensed
and exploded, several things formed.
The first thing that formed was the different
Galaxies. There are 3 types of galaxies. Our
Galaxy is the Milky Way. Yummmmm!
The second thing that formed was the Sun. It
provided heat for the planets, including
earth.
Next and last they earth began to take shape,
form and grow.
Types of
Galaxies
What is a galaxy?
A galaxy is a huge cluster of stars, dust,
and gas held together by gravity.
 Large galaxies have more than a trillion
stars while small galaxies have fewer than
a billion.
 Astronomers believe that there are billions
of galaxies in the universe.
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Basic Types of
Galaxies
Spiral
Elliptical
Irregular
Spiral Galaxy
Shaped like pinwheels
 Sweeping “arms” made
of gas, dust, and
younger stars, rotate
around the galaxy’s
center called a bulge.
 The bulge is a dense
group of old stars
 Our Milky Way Galaxy is
a Spiral Galaxy.
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Milky Way Galaxy
 Our
solar system
is located on one
of the spiral
arms called the
Orion Arm.
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All of the stars we
see at night are
part of the Milky
Way Galaxy.
Elliptical Galaxies
 Among
the largest
galaxies in the universe
 Looks like a snowball
 Contains mostly older
stars that rotate
around the center of
the galaxy in an
unorganized fashion
Elliptical Galaxy
Irregular Galaxies
Least common type of
galaxy
 Smaller and shapeless
 Contains very hot
newer stars and older
stars
 May form when two
galaxies collide
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Irregular Galaxy
Gravity
Gravity is the force between all objects
that pulls them together.
 Gravity Keeps the planets in orbit around
the sun. Gravity keeps you and all objects
on earth.
 2 factors affect gravity- Mass of an object
and distance between objects.
 For example- Mercury has more gravity to
the sun than earth because the distance is
shorter between them.
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Inertia
Inertia is a law that states that all objects
will stay in motion until stopped by another
force.
 For example- gravity holds the planets in
orbit but inertia keeps the planets moving.
 The moon has both gravity and inertia.
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Our 8 Planets
Mr. Smith
The Sun
Made of mainly gases.
 Much larger than any planet in the solar
system.
 Creates the gravity needed to hold planets
in orbit.
 The sun is the only star in our solar
system. All other stars are in our galaxy
outside our main system.
 As you look into the night sky, your seeing
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Continued……Sun
The sun is made up of 6 parts; The
Corona, Chromospheres, photosphere,
Convective zone, radiative zone and the
core.
 When you look at the sun your seeing the
Photosphere.
 The Corona is the suns atmosphere
 The Convective zone is where the gases
circulate
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Continued……Sun
Will the sun burn out or shrink?
 Scientist have found out that the suns
energy comes from nuclear fusion.
 Fusion is the joining of two atoms to create
energy.
 The energy created from hydrogen atoms
fusing creates helium atoms. It then gets
sent into other layers and eventually
reaches the surface in the form of light
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Sun
Mercury
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1st planet from the sun
Shortest revolution/year=88 earth days
Rotation/day=58 earth days
Rotates retrograde (clock wise)
Much smaller than earth and the smallest planet
Its atmosphere is made of Oxygen, sodium, helium
Mercury is a terrestrial planet
Terrestrial means the type of surface
Mercury has little to no atmosphere and manly
composed of Oxygen, sodium and helium.
Temperature ranges from -297 at night and 872
degrees F during day.
Mercury
Venus- When a volcano meets a tornado!
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2nd planet closest to the sun and the planet
before earth.
Most like the Earth
Slightly Smaller than earth
Retrograde rotation- Counter clockwise
2nd fastest revolution of all planets
Covered by a layer of clouds that trap heat and
covered by volcanoes.
Temperature=856 degrees F
Atmosphere made of carbon dioxide(soda’s)
Rotation= 243 earth days)
Revolution= 224 earth days/ 1venus year
Venus
Earth- The 3rd rock from the sun!
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Most complex planet with every system- water, air,
land and life.
5th largest in solar system
23 degree tilt on axis
70 percent of earth is covered by water
Mostly 0-100 degrees
Atmosphere 78% nitrogen and 21% oxygen
3 layers of surface- Crust, mantle and core
Revolution= 365 days in
Rotation=24 hours
Prograde Rotation which means counter
clockwise.
Earth and moon
Mars
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Often called the Red Planet,
Mars means God of War
Known to have water in its polar area that is frozen.
Atmosphere made of Carbon Dioxide
Temperature ranging from -225 to 62 degree F.
7th largest planet
4th shortest year/4th shortest revolution around the sun.
Takes 1.8 earth years.
Has the Largest Volcano in the solar system called
Olympus Mons, 15 miles high and 400 miles wide
Rotation= 24 hr 37 min
Revolution= 1.88 earth years/ 1 mars year
Mars
Mars and its moons
Jupiter
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Jupiter’s name means, King of the Roman Gods
First of the Gas Giants and majority of the planet is
made of gas/very little is solid.
The largest planet in the solar system
Rotation/day=9 earth hours
Revolution/year=11.8 earth years
Atmosphere made of Hydrogen and Helium
Has 28 moons. The 4 largest are called the “Galician
Satellites” named after Galileo who found them.
318 times the size of Earth
Known for having “the Great Red Spot” which is a
Hurricane on the surface of Jupiter.
Jupiter
Jupiter's moons
Saturn
Saturn’s Moons
Neptune
Neptune’s Moons
Uranus
Uranus Moon’s