Download Revolve / Orbit

Revolve / Orbit
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To revolve around something means to travel around it.
The planets revolve around/orbit the sun. So, a revolution would be one complete
trip around the sun.
One revolution around the sun = one year.
It takes Earth 365 ¼ days to orbit the sun. Earth does not travel in a circular orbit
around the sun. It travels in an elliptical pathway.
1 year on Earth = 12 months = 52 weeks = 365 ¼ days
The moon revolves around Earth. It takes the moon about 29.5 days to make one
revolution around the Earth.
Questions:
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What does it mean to revolve?
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How long does it take Earth to revolve around the sun?
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What are some equivalent measurements to one year on Earth?
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Does the moon revolve? If so, around what does the moon revolve?
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How long does it take the moon to make one revolution around Earth?
Rotate / Axis
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Earth rotates on an axis. This axis is an imaginary line that passes through Earth’s
center from the North Pole to the South Pole.
It takes Earth 24 hours (1day) to rotate on its axis. This causes day and night.
At any time, half of Earth faces the sun, and half faces away from the sun. The
half facing the sun has daytime and the other half has nighttime.
Because Earth rotates, it makes the sun, moon, and stars appear to be moving
across the sky.
The moon also rotates, but it rotates much slower. It takes the moon about 29.5
days to make one complete rotation.
Questions:
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What is an axis?
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What is Earth doing when it is rotating on its axis?
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Is the sun really moving? If not, why does it look like it is moving?
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How long does it take Earth to make one complete rotation?
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Why do we have day and night on Earth?
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Does the moon rotate? If yes, how long does it take the moon to make one
rotation?
Moon / Phase
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The moon does not always look the same each night. Sometimes the moon looks
very large and other times it looks like a tiny sliver. These changes in how the
moon looks to us on Earth are called moon phases.
The moon does not actually change shape. It only appears to change shape.
The moon does not create its own light. It reflects the light of the sun.
The phases of the moon include: new moon, waxing crescent, first quarter,
waxing gibbous, full moon, waning gibbous, third quarter, and waning
crescent. These phases repeat over and over. (Note: the bold print phases are the
phases students are responsible for.)
During a new moon, the moon is directly between the sun and Earth. Because of
this, the side of the moon facing Earth is dark (showing no reflected light).
During a full moon, the moon is on the opposite side of Earth from the sun. The
entire side of the moon facing Earth reflects sunlight back to Earth. It appears to
be a complete circle.
The moon is similar to Earth in that they are both spherical in shape, they are both
composed of rocks, they both have landforms, and they both rotate and revolve.
Unlike Earth, the moon has no atmosphere and therefore no weather or wind. The
moon also does not have any liquid water on its surface.
Questions:
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What is the moon composed of?
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How are Earth and the moon similar?
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Why is there no life on the moon?
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Does it rain on the moon?
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Why does the moon appear to change shapes in the sky?
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How long does it take the moon to rotate and revolve?
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How does the moon appear during a new moon? What quarter moon would come
after a new moon?
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How does the moon appear during a full moon? What quarter moon would come
after a full moon?
Solar Eclipse / Lunar Eclipse
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An eclipse happens when one object in space casts a shadow on another object in
space.
In a solar eclipse, the moon is in between the sun and Earth causing a shadow to
fall on Earth.
Sun
Moon
Earth
It is very important to protect your eyes during a solar eclipse.
In a lunar eclipse, the moon is dark because the Earth is blocking the sun’s light.
Sun
Earth
Moon
Questions:
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What is the difference between a solar and lunar eclipse?
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Why do you have to protect your eyes during a solar eclipse?
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Why does the moon look dark during a lunar eclipse?
Earth
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Earth is the third planet from the sun.
Earth has an atmosphere made up of many different gases that help to support life.
Earth has fresh and saltwater to support life.
Earth has three layers (crust, mantle, core)
Earth is shaped like a sphere.
Earth landmasses occur on plates that are constantly moving.
Earth has many different landforms that occur due to constructive and destructive
forces.
Earth spins on its axis (rotates). It takes Earth 24 hours (one day) to complete one
rotation.
Earth is tilted about 23.5 degrees on its axis. This is why we have seasons.
Earth revolves around the sun. It takes Earth 1 year (365 ¼ days) to complete one
revolution.
Earth’s main energy source is the sun.
Questions:
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Where is Earth located in the solar system?
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How does the size of Earth compare to that of the moon? The sun?
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Why is Earth able to have life on it when other planets cannot?
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Does the earth or the moon have a stronger pull of gravity?
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Describe the three layers of Earth.
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How long does it take Earth to revolve around the sun?
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How long does it take Earth to complete one rotation?
Gravity
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Gravity is a force that pulls objects toward each other.
The more mass an object has, the greater its force of gravity.
Since the sun’s mass is so large in comparison to the planets, the sun’s gravity is
much stronger than that of the other planets. Everything in the solar system is
kept in orbit by the pull of the sun’s gravity.
The force of gravity on each planet and moon is different, depending on its size
and distance from the sun.
There is less gravity on the moon than there is on Earth. The moon’s gravity still
has an effect on Earth. It causes the high and low tides.
Weight is a measure of the pull of gravity. A spring scale is used to measure
weight.
An object’s weight can change depending on where it is located in the solar
system, but the mass of the object will remain the same.
Questions:
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What is gravity?
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Why do all the planets orbit the sun?
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Why would you weigh less on the moon than you do on Earth?
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What measurement tool is used to measure the force of gravity?
Comets, Meteoroids, Asteroid Belt
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Comets are mountain-size chunks of ice and dust that orbit the sun.
Some comets orbit the sun over and over again. Others crash into the sun.
Meteoroids are small space rocks that orbit the sun.
Meteoroids occasionally enter Earth’s atmosphere, but they are usually burned up.
If they do manage to strike Earth’s surface, they are called meteorites.
When meteorites make contact with the surface of planets or moons, they can
cause craters (deep depressions in the surface) to form.
The asteroid belt occurs in the large space between the orbit of Mars and the orbit
of Jupiter.
In this space is a belt of small and large rocks (asteroids).
Asteroids do not have an atmosphere.
Sun / Sunspots
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The sun is an average size star at the center of our solar system.
The sun is made up of hot gases.
Everything in the solar system revolves around the sun. This occurs because of
the pull of the sun’s gravity.
The sun rotates on its axis.
Solar energy is energy from the sun. The sun is the major energy source for all
of Earth.
The sun has sun spots that are cooler and darker than the rest of the sun.
Solar Energy Uses: heat Earth’s land and water, energy source for
photosynthesis, make electricity for solar houses/cars.
Solar energy can be changed to other forms of energy.
Questions:
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What is the sun and what is it made up of?
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Where is the sun located in the solar system?
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What does the sun provide energy for?
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What are sunspots?
Solar System
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Our solar system includes the sun, the planets and their moons, comets, asteroids,
and meteoroids.
The sun is the center of the solar system.
The order of the planets from the sun is: Mercury, Venus, Earth, Mars, Jupiter,
Saturn, Uranus, and Neptune.
There is an asteroid belt between the orbits of Mars and Jupiter.
All planets and their moons revolve around the sun. The planets do not all
revolve in the same amount of time. The close the planet is to the sun, the shorter
amount of time it takes for it to revolve around the sun.
Questions:
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What makes up our solar system?
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How does the length of one revolution around the sun differ between planets?
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What is the order of the planets?
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Which two planets neighbor Earth?