Download Notes: Sun-Earth-Moon System

Notes: Sun-Earth-Moon System
A. The Earth
1. ____Axis__ - imaginary vertical line around
which Earth spins
2. _Rotation___– the spinning of Earth around its axis
that causes day and night
3. _Revolution__– Earth’s yearly orbit around the Sun
a. Earth’s orbit is an __ellipse___, or elongated,
closed curve
b. Because the Sun is not centered in the ellipse,
the distance between Earth and the Sun
changes during the year (video clip: Planetary Rotation and Revolution)
4. Earth’s __tilt____ causes seasons
a. The hemisphere tilted toward the Sun receives
more daylight hours and radiation than the
hemisphere tilted away from the Sun
b. The longer period of sunlight is one
reason summer is warmer than winter
Let’s Illustrate: Reason for the Seasons (video clip Earth’s Tilt on It’s Axis)
B.
The Moon
1. Motions of the Moon
a. ___Rotation___ on its axis which takes about _29.5_
days, with the same side always facing Earth. (video clip: movement of the
moon)
b. Shines because it reflects sunlight (video clip: Why we always see the same side of the
moon)
2. Phases of the Moon
a. _New Moon____– the moon is between Earth and the
Sun and cannot be seen
b. __Waxing______– more and more of the lighted side of
the moon can be seen each night (waxing crescent,
first quarter, waxing gibbous)
c. __Full Moon____– all of the moon’s lighted side is visible
d. __Waning____– less and less of the lighted side of the
moon can be seen each night (waning gibbous, third
quarter, waning crescent) (video clip: phases of the moon)
3. Eclipses – when the Earth or the Moon casts a shadow on the
other
a. Solar Eclipse - the moon moves directly
between Earth and the Sun, shadowing part of Earth;
occurs during the day ; during a new moon (video clip: solar eclipse)
(video clip: Sun’s corona during a solar eclipse)
b. Lunar Eclipse - the Earth’s shadow falls on the moon;
occurs at night ;during a full moon (video clip: lunar eclipse)
4. Tides - at any shoreline on Earth, the height
of the water will rise and fall throughout the
day. Gravity is responsible for these regular
increases and decreases.
a. The moon’s gravity pulls on Earth.
1.) This pull creates a bulge of water on
the side of Earth facing the Moon.
2.) Earth’s rotation and inertia creates a
bulge on the opposite side of Earth
as well
3.) The two bulges create high tides and
between the two bulges are low
tides.
(video clip: tides)
b. The sun’s force on the tides is less than
half of the effect of the Moon.
1.) It creates two additional bulges
a.) Spring Tide - the sun, moon,
and earth align during a new and full
moon and high-tide waters are
higher than normal
b.) Neap Tide - when the moon is in
the first or third quarter and high
tides are lower than normal and
low tides are higher than normal
C. The Sun
1. Solstice - the day when the Sun reaches its
greatest distance north or south of the equator
a. Summer Solstice - occurs June 21 or 22 in
the northern hemisphere
b. Winter Solstice - occurs December 21 or 22 in
the northern hemisphere
2. Equinox - the day when the Sun is directly over
Earth’s equator
a. Daylight and nighttime hours are equal
all over the world
b. Spring Equinox occurs on March 20 or
21 in the northern hemisphere
c. Fall Equinox
occurs on September 22
or 23 in the northern hemisphere
Life Cycle of Stars
• 1. Nebula – how a star begins as a large cloud of gas
and dust; gravitational force causes the nebula to
contract; it breaks into smaller pieces when gas and
dust become so hot that nuclear fusion starts; A
STAR IS BORN. Stars spend many years in a
relatively constant state. The center shrinks, and
the outer part of the star expands.
Life of an Average Star
• 2. All average stars, including our Sun, eventually
becomes a Red Giant.
• 3. Planetary Nebula – the outer part of the red giant
grows larger until it eventually drifts into outer space.
• 4. The hot outer core left behind is a White Dwarf. A
white dwarf is about 1 million times as dense as the
Sun. Most of its fuel is gone, so it not longer
produces energy. It gives off enough leftover heat to
glow faintly for perhaps a billion years. It continues
to cool until it becomes cold and dark. It is then
called a Black Dwarf.
Life of a Massive Star
• 2. If the star is a massive star, it becomes a Supergiant.
• 3. The core eventually collapses violently, sending a shock
wave outward through the star. The outer portion explodes
producing a Supernova. This can be million of times brighter
than the original star.
• 4. Material left from a supernova is called a Neutron Star.
These are about twice as massive as the Sun and very dense.
• 5. If material left over from the supernova is more than
three times as massive as the Sun, it becomes a Black Hole
because the core collapses. The gravity from this mass is so
strong that nothing can escape from it, not even light.
• Stars take different lengths of time to go through their life
cycle. The length of a star’s life depends on its mass.
The most massive stars live the shortest lives because
they use up their fuel more quickly than stars with less
mass. The life cycle of a star is often compared with that
of the Sun, which is an average star. In about 5 billion
years, the Sun will become a giant. Now it is a main
sequence star, between an average star and a red giant.
The Sun has an expected lifetime of about 10 billion years.
How are Stars Classified?
• All stars are huge spheres of glowing gas. Made up
mostly of hydrogen, stars produce energy through
nuclear fusion.
• Stars are classified according to color, temperature,
size, composition, and brightness.
• The brightness of a star is described in two ways:
1. apparent magnitude – is a star’s brightness as
seen from Earth
2. absolute magnitude – is the brightness the star
would have if it were a standard distance from
Earth; actual brightness
H-R Diagram
• About 100 years ago, two scientists Ejnar Hertzsprung and Henry
Norris Russell made a graph to find out if the temperature and
brightness of stars are related. They plotted the surface
temperatures of stars on the x-axis and their absolute brightness on
the y-axis. The points formed a pattern. This graph is still used
today, called the Hertzsprung-Russell diagram.
Main Sequence- diagonal band on H-R diagram (about 90% of stars)
* Upper Left – hot, blue, bright stars
* Lower Right – cool, red, dim stars
* Middle – average yellow stars like the Sun
The other 10% are dwarfs, giants and super giants.
The Solar System
• The Solar System is made up of 8 planets, the Sun, many
small objects, and a huge volume of space.
• The sun is the center of our Solar system.
• All objects in the solar system revolve around the sun.
• Gravity holds the solar system together. About 99.85% of the
mass of the entire solar system is contained within the sun.
• Distances within the solar system are so large that they are
measured using astronomical units. One astronomical unit
(AU) equals the average distance between Earth and the sun,
about 150,000,000 km.
• A planet is round, orbits the sun, and has cleared out the
region of the solar system along its orbit. All except Mercury
and Venus have at least one natural satellite, or moon.
• A dwarf planet is an object that orbits the sun and has
enough gravity to be spherical, but has not cleared the area
of its orbit.
• The solar system also includes many smaller objects that orbit
the sun, such as asteroids and comets.
• Scientists think the solar system formed about 4.6 billion
years ago from a cloud of hydrogen, helium, rock, ice, and
other materials pulled together by gravity.
• Planets began to form as gravity pulled rock, ice, and gas
together. The rock and ice formed small bodies called
planetesimals.
• Over time, planetesimals collided and stuck together,
eventually combining to form all the other objects in the solar
system.
• Close to the sun, the inner planets are small and rocky.
• Farther from the sun, the outer planets are gas giants.
• Beyond the gas giants, ice and other materials produced
comets and dwarf planets.
The Planets
• Inner Planets (Terrestrial Planets)
– Small, dense, rocky surface
with iron cores
– Includes: Mercury, Venus,
Earth, Mars
• Outer Planets (Gas Giants)
– Large, lightweight, no solid surface,
have many moons
– Made up of liquid and gases
– Includes: Jupiter, Saturn, Uranus
and Neptune
Inner Planets
• Closest to the Sun; 36 million miles from the Sun
• Smallest planet; 4,879 km in diameter (not much larger than
Earth’s moon)
• Revolution (Orbit) – 88 days Rotation – 58.9 days
• No Moons
• Thin atmosphere is constantly replenished by the solar wind
• Surface is rocky and cratered
• Temperatures range from 430⁰C to -170⁰C
• Much of what we know about Mercury
has come from space probes.
• Second from the sun; 67 million miles from the Sun
• Similar to Earth in size and mass, called “Earth’s twin”; 12,104
km in diameter
• Revolution (Orbit) – 224.7 days Rotation – 244 days
• No Moons
• Brightest planet
• Extremely dense atmosphere of clouds.
The pressure of Venus’s atmosphere is
90 times greater than Earth’s
• Has the hottest surface of any planet.
Surface temperature of 450⁰C
• Rocky surface with volcanic cracks
• Third planet from the Sun
• More than 70% of the surface is covered in water
• Earth is “just right” for life as we know it. Earth is not too
hot or too cold.
• Earth is the only planet with an atmosphere that is rich in
oxygen and it traps heat. The atmosphere protects the
surface from most meteors and the Sun’s radiation.
• One large Moon
• Only planet where life
is known to exist
• Fourth planet from the Sun; 141.5 million miles from the Sun
• Called the Red Planet because of iron-rich rocks, leaving a rusty dust
behind
• 6,794 km in diameter
• Revolution (Orbit) – 2 years
Rotation – 24 ½ hours
• 2 small Moons: Phobos and Deimos
• Scientists think that liquid water flowed on Mars’s surface in the
distant past.
• Has dust storms that cover the planet for days
• Has largest volcano in the solar system –
Olympus Mons
• Thin atmosphere of mostly carbon dioxide
• Tilted on its axis; which causes seasons
Outer Planets
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5th from the Sun; 483.3 million miles form Sun
Largest planet; 142,984 km in diameter
Revolution (Orbit) – 11.9 years Rotation – 9.9 hours
At least 63 Moons; Galileo discovered the largest moons in
1610 – Io, Europa, Ganymede, and Callisto
• Thick gas atmosphere of mostly hydrogen and helium
• Storms swirl the planet; the largest being the Great Red Spot
(larger than Earth!)
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6th planet; 886 million miles form the Sun
Second largest planet; 120,536 km in diameter
Revolution (Orbit) – 29.5 years Rotation – 10.7 hours
Has beautiful rings around it (thousands of them); made of
chunks of ice and rock
• At least 61 moons; the largest Titan is larger than Mercury
• Thick gas atmosphere (hydrogen and helium); clouds and
storms
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First seen in 1781
7th from the Sun; 1,778 million miles from Sun
Twice as far from the sun as Saturn, so it is much colder.
51,118 km in diameter (much smaller than Jupiter and
Saturn)
Revolution (Orbit) – 83.8 years Rotation – 17.2 hours
At least 27 Moons
Ocean of water and ammonia
It looks blue-green because of traces
of methane in its atmosphere
Thin rings
Axis of rotation is tilted at an angle of 90⁰ from the vertical.
Rotates from top to bottom instead of side to side.
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8th planet: 2,793 million miles from Sun
49,528 km in diameter
Revolution (Orbit) – 163.8 years Rotation – 16.1 hours
Cold, Blue-green planet
2 main rings, 3 small rings
At least 13 moons
Poisonous thick gas atmosphere
The Great Dark Spot was probably a
giant storm. Images taken 5 years
later showed that the spot was gone.
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Last planet to be discovered (1930)
3,660 million miles form the Sun
2,000 miles in diameter
Revolution (Orbit) – 248 years Rotation – 6 days
1 moon, Charon, half the size of the planet
Small, rocky, made of methane ice
In 2006 Pluto was demoted from being a planet and is now
classified as a dwarf planet
Notes: Sun-Earth-Moon System
A. The Earth
1. __________– imaginary vertical line around
which Earth spins
2. _________– the spinning of Earth around its axis
that causes day and night
3. _________– Earth’s yearly orbit around the Sun
a. Earth’s orbit is an __________, or elongated,
closed curve
b. Because the Sun is not centered in the ellipse,
the distance between Earth and the Sun
changes during the year
4. Earth’s _________ causes seasons
a. The hemisphere tilted toward the Sun receives
more daylight hours and radiation than the
hemisphere tilted away from the Sun
b. The longer period of sunlight is one
reason summer is warmer than winter
Let’s Illustrate: Reason for the Seasons
B.
The Moon
1. Motions of the Moon
a. ____________on its axis which takes about _____
days, with the same side always facing Earth.
b. Shines because it reflects sunlight
2. Phases of the Moon
a. _____________– the moon is between Earth and the
Sun and cannot be seen
b. _____________– more and more of the lighted side of
the moon can be seen each night (waxing crescent,
first quarter, waxing gibbous)
c. ____________– all of the moon’s lighted side is visible
d. ____________– less and less of the lighted side of the
moon can be seen each night (waning gibbous, third
quarter, waning crescent)
3. _______________– when the Earth or the Moon casts a shadow on
the other
a. _____________- the moon moves directly
between Earth and the Sun, shadowing part of Earth;
occurs during the _____; during a ___________
b. _____________ - the Earth’s shadow falls on the moon;
occurs at ________; during a _________
4. ________– at any shoreline on Earth, the height
of the water will rise and fall throughout the
day. __________ is responsible for these
regular increases and decreases.
a. The moon’s gravity pulls on Earth.
1.) This pull creates a bulge of water on
the side of Earth facing the Moon.
2.) Earth’s rotation and inertia creates a
bulge on the opposite side of Earth
as well
3.) The two bulges create high tides and
between the two bulges are low
tides.
b. The sun’s force on the tides is less than
half of the effect of the Moon.
1.) It creates two additional bulges
a.) ______________– the sun, moon,
and earth align during a new and full
moon and high-tide waters are
higher than normal
b.) _____________– when the moon is in
the first or third quarter and high
tides are lower than normal and
low tides are higher than normal
C. The Sun
1. _____________– the day when the Sun reaches its
greatest distance north or south of the equator
a. ______________occurs June 21 or 22 in
the northern hemisphere
b. ______________occurs December 21 or 22 in
the northern hemisphere
2. ____________– the day when the Sun is directly over
Earth’s equator
a. Daylight and nighttime hours are equal
all over the world
b. _______________occurs on March 20 or
21 in the northern hemisphere
c. ________________ occurs on September 22
or 23 in the northern hemisphere
The Solar System
• The ________________is made up of _____________, the
________, many ___________________, and a huge
________________________.
• The sun is the ________________of our Solar system.
• All objects in the solar system ___________around the ____.
• __________holds the solar system together. About ________
of the mass of the entire solar system is contained within the
_________.
• Distances within the solar system are so large that they are
measured using ______________________. One astronomical
unit (_____) equals the average distance between
_________________, about __________________.
• A ___________ is __________, ________________, and has
__________________________ of the solar system along its
orbit. All except Mercury and Venus have at least one natural
satellite, or moon.
• A ___________________ is an object that orbits the sun and
has enough gravity to be spherical, but has _______________
_______________________.
• The solar system also includes many smaller objects that orbit
the sun, such as ______________ and _______________.
• Scientists think the solar system formed about _______billion
years ago from a cloud of ___________, ____________,
_____, ______, and other materials ____________________
_____________________.
• Planets began to form as gravity pulled rock, ice, and gas
together. The rock and ice formed ________________ called
________________________.
• Over time, planetesimals collided and stuck together,
eventually combining to form all the other objects in the solar
system.
• _________to the sun, the inner planets are _____________.
• _________from the sun, the outer planets are ___________.
• __________the gas giants, ice and other materials produced
comets and dwarf planets.
The Planets
• Inner Planets (Terrestrial Planets)
– __________, dense, ___________surface
with __________________
– Includes: Mercury, Venus,
Earth, Mars
• Outer Planets (Gas Giants)
– _______, ___________, no solid
surface, have __________________
– Made up of liquid and gases
– Includes: Jupiter, Saturn, Uranus
and Neptune
Inner Planets
• ________________________; 36 million miles from the Sun
• ________________ planet; 4,879 km in diameter (not much
larger than Earth’s moon)
• Revolution (Orbit) – 88 days Rotation – 58.9 days
• _______________________
• _____atmosphere is constantly replenished by the solar wind
• Surface is _________and _____________
• Temperatures range from 430⁰C to -170⁰C
• Much of what we know about Mercury
has come from space probes.
• Second from the sun; 67 million miles from the Sun
• __________________ in size and mass, called “Earth’s
________”; 12,104 km in diameter
• Revolution (Orbit) – 224.7 days Rotation – 244 days
• ____________________
• ______________ planet
• Extremely _________________of clouds.
The pressure of Venus’s atmosphere is
90 times greater than Earth’s
• Has the ________________of any planet.
Surface temperature of 450⁰C
• Rocky surface with volcanic cracks
• Third planet from the Sun
• More than ____% of the surface is ____________________
• Earth is “just right” for life as we know it. Earth is _______
______________________
• Earth is the only planet with an atmosphere that is rich in
__________and it ___________. The atmosphere protects
the surface from most meteors and the Sun’s radiation.
• ______________________
• Only planet where ________
is known to exist
• Fourth planet from the Sun; 141.5 million miles from the Sun
• Called the __________________ because of iron-rich rocks, leaving a
____________________ behind
• 6,794 km in diameter
• Revolution (Orbit) – 2 years
Rotation – 24 ½ hours
• 2 small Moons: ____________and Deimos
• Scientists think that ______________________flowed on Mars’s
surface in the distant past.
• Has dust storms that cover the planet for days
• Has largest volcano in the solar system –
____________________________
• Thin atmosphere of mostly carbon dioxide
• ____________on its axis; which causes seasons
Outer Planets
•
•
•
•
5th from the Sun; 483.3 million miles form Sun
_____________________; 142,984 km in diameter
Revolution (Orbit) – 11.9 years Rotation – 9.9 hours
At least _____Moons; ______________ discovered the
largest moons in 1610 – Io, Europa, Ganymede, and Callisto
• Thick gas atmosphere of mostly hydrogen and helium
• Storms swirl the planet; the largest being the
_____________________ (larger than Earth!)
•
•
•
•
6th planet; 886 million miles form the Sun
____________________________; 120,536 km in diameter
Revolution (Orbit) – 29.5 years Rotation – 10.7 hours
Has __________________________ around it (thousands of
them); made of chunks of ice and rock
• At least ___moons; the largest _______is larger than Mercury
• Thick gas atmosphere (hydrogen and helium); clouds and
storms
•
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•
•
•
•
•
•
•
•
First seen in 1781
7th from the Sun; 1,778 million miles from Sun
_________as far from the sun as Saturn, so it is much _____.
51,118 km in diameter (much ___________than Jupiter and
Saturn)
Revolution (Orbit) – 83.8 years Rotation – 17.2 hours
At least _____Moons
Ocean of water and ammonia
It looks blue-green because of traces
of _______________in its atmosphere
__________rings
Axis of rotation is tilted at an angle of ____⁰ from the vertical.
Rotates from ____________________instead of side to side.
•
•
•
•
•
•
•
•
8th planet: 2,793 million miles from Sun
49,528 km in diameter
Revolution (Orbit) – 163.8 years Rotation – 16.1 hours
_________, ________________ planet
2 main rings, 3 small rings
At least _____moons
______________thick gas atmosphere
The ________________was probably a
giant storm. Images taken 5 years
later showed that the spot was gone.
•
•
•
•
•
•
•
Last planet to be discovered (1930)
3,660 million miles form the Sun
2,000 miles in diameter
Revolution (Orbit) – 248 years Rotation – 6 days
1 moon, Charon, half the size of the planet
_________, ____________, made of ___________________
In _________Pluto was _______________from being a
planet and is now classified
as a ___________________