Transcript Earth and Space

Earth and Space
Earth’s Place in Space
*Earth moves around the
sun.
A. Earth’s Rotation
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Earth spins around an
imaginary line running
through its center called
an axis. It is slightly
tilted.
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The spinning of Earth on
its axis is called Earth’s
rotation.
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It rotates once every 24
hours (1 day and night).
B. Earth’s Revolution
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The movement of Earth around the sun
in known as Earth’s Revolution.
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It takes Earth 1 year to complete one
revolution.
C. Seasons
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The Earth’s tilt and revolution around the
sun causes seasons.
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Summer occurs when your part of the
Earth is tilted towards the sun. The days
are long and the nights are short.
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Winter occurs when your part of the
Earth is tilted away from the sun and the
slanted rays of the sun are weak. The
days are short and the nights are long.
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Spring and fall occur when Earth is not
tilted toward or away from the sun.
D. Movements of the Moon
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The moon constantly circles the Earth as Earth
revolves around the sun.
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Although it looks different at different times of
the month, it doesn’t change – the way we see
it does.
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The sun lights up the moon.
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The movement of the Earth is what causes
night and day.
D. Movements of the
Moon (cont.)
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When the moon and
sun are on opposite
sides of Earth, a full
moon occurs.
When the moon and
sun are on the same
side as Earth, a new
moon occurs. This
is when the side of
the moon that is lit
by the sun faces
away from Earth.
Full Moon
New Moon
Phases of the Moon
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Solar eclipse: when the moon is between
the Earth and Sun.
Diagram of a Solar Eclipse
Total Solar Eclipse (2001)
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Lunar eclipse: when the Earth is between
the sun and moon.
Stages of a Lunar Eclipse
Space – How are we connected?
Universe
Galaxy
Milky Way
Our Solar System
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Universe: the vast
expanse of space
which contains all of
the matter and energy
in existence.
EVERYTHING is a part
of it. IT IS HUGE!!!
Galaxy: a cluster of
starts, dust, and gas
which is held together
by gravity.
Astronomers suggest
there may be as many
as 100 billion!! They
are scattered
throughout the
universe and vary
greatly in size.
The Universe (several galaxies
can been seen)
Spiral Galaxy
*Galaxies are classified by scientists according to their
size and shape.
1. irregular – no definite shape
2. spiral – pinwheel shape (our galaxy)
3. elliptical – go from round to
flat discs
*galaxies range from a few thousand
to a million light years in diameter.
Spiral (Andromeda)
Elliptical
Irregular
Solar System
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Made up of 8 planets and other objects
that orbit the sun.
To measure distances in space, scientists
use an astronomical unit (AU). 1 AU =
150 million km, which is the average
distance from Earth to the sun.
A light year is 9.5 trillion
(9,500,000,000,000) kilometers and is the
distance light travels in one year.
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Planet: round ball
of gas or rock that
travels around a
star – and the path
it takes around a
star is called its
orbit.
Inner Planets:
Mercury, Venus,
Earth, Mars
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Outer Planets: Jupiter, Saturn,
Uranus, Neptune.
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Saturn is not the
only planet with
rings. Jupiter,
Uranus, & Neptune
do too.
Pluto is now
considered a dwarf
planet.
The Stars and Sun
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The stages a star goes through in its
life depend on the star’s size.
The smallest stars shine the longest.
Scientists hypothesis that stars begin
their lives as nebulae (clouds of gas
and dust).
A large-size star can end its life cycle
as a neutron star or a black hole.
The sun is a medium-sized star.
The Stars and Sun, cont.
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In about 5 billion years our sun will
become a giant.
At the end of our sun’s life cycle, it will
become a black dwarf.
The Sun and Stars, cont.
Constellations: patterns formed by
groups of stars.
*They are named for people, animals, or
commons objects and were used as
reference points in the sky by sailors.
*Because the Earth is moving, the stars that
are visible at night constantly change.
*As the Earth revolves around the sun,
different constellations are seen
throughout the year.
Examples of Constellations…
The Big Dipper (Ursa Major)
The Little Dipper (Ursa Minor)
Our Galaxy
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Our galaxy is called the Milky Way.
The shape of our galaxy is spiral (looking down
it looks like a pinwheel)
It contains: stars (billions!), nebulae (clouds of
dust and gas), planets, and asteroids.
It is approximately 100 light years in diameter.
All objects in the Galaxy revolve around the
Galaxy’s center.
It takes the Sun 250 million years to pull us
through 1 revolution around the center of the
Milky Way.
The Milky Way Galaxy