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A
Name the 8 phases of the moon in order, starting from any point in the cycle.
Draw what relative positions of the Sun, Moon, and Earth would cause each phase.
If a Lunar Eclipse is happening, what phase must the Moon be in? Why?
If a Solar Eclipse is happening, what phase must the Moon be in? Why?
Using only words, explain what causes the Phases of the Moon.
B
Name the planets of our Solar System in order:
How do the relative sizes of the outer planets (Jupiter out) and the inner planets (Mars in)
contrast?
The object that the planets all orbit around is the:
Draw a diagram that roughly shows the relative distances of the 8 planets from the Sun.
How many stars are there in our Solar System?
C
Explain with words only why we have day and night here on Earth.
Draw a diagram that shows why we have day and night here on Earth.
Draw a diagram that shows the relative positions of the Sun, Earth, and Moon during a Lunar Eclipse.
Draw a diagram that shows the relative positions of the Sun, Earth, and Moon during a Solar Eclipse.
Why don’t Eclipses happen every time there is a Full or New Moon?
D
What is the relationship between the masses of two objects and the force of gravity between them?
What is the relationship between the distance between two objects and the force of gravity between them?
An object in orbit around another object is falling toward it. It just keeps moving forward at the right speed so
that it falls around it, rather than into it. But what would happen to the orbiting object if gravity suddenly
disappeared? What would happen if gravity increased or decreased?
E
What could be described as “made up of” galaxies?
What could be described as “made up of” stars?
What could be described as “made up of” planets?
About how many stars are in a galaxy?
About how many galaxies are in the Universe?
How far apart are stars from each other compared to how far planets are from their star?
A
Name the 8 phases of the moon in order, starting from any point in the cycle.
New → Waxing Crescent → First Quarter (or Waxing Half) → Waxing Gibbous → Full → Waning Gibbous →
Third Quarter (or Waning Half) → Waning Crescent → New
Draw what relative positions of the Sun, Moon, and Earth would cause each phase.
(see diagram in your journal)
If a Lunar Eclipse is happening, what phase must the Moon be in? Why?
A Lunar Eclipse is when the Earth’s shadow falls on the Moon. For that to happen the Sun, Earth, and Moon must be in a
line (in that order). This is the alignment that creates a full moon…when the side of the Moon that faces the Earth is also
the side that is lit up by the Sun.
If a Solar Eclipse is happening, what phase must the Moon be in? Why?
A Solar Eclipse is when the Moon’s shadow falls on the Earth. For that to happen the Sun, Moon, and Earth must be in a
line (in that order). This is the alignment that creates a New Moon…when the side of the Moon that faces the Earth is
not lit up by the Sun at all.
Using only words, explain what causes the Phases of the Moon.
As the Moon revolves around the Earth across 29 days the relative positions of the Earth, Moon, and Sun are constantly
changing. The side of the Moon that faces the Sun is always lit up by it. But on Earth, depending on where the Sun and
Moon are relative to us, we don’t always see all, or at New any of the lit up part.
B
Name the planets of our Solar System in order:
Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune
How do the relative sizes of the outer planets (Jupiter out) and the inner planets (Mars in) contrast?
The outer planets are many, many times bigger than the inner ones.
The object that the planets all orbit around is the:
Sun
Draw a diagram that roughly shows the relative distances of the 8 planets from the Sun.
How many stars are there in our Solar System?
One
C
Explain with words only why we have day and night here on Earth.
As the Earth rotates around over 24 hours the part of the Earth that you are on will for part of the 24 hours be facing
toward the Sun and be lit up by it and for part of the 24 hours be facing away from the Sun and not be lit up.
Draw a diagram that shows why we have day and night here on Earth.
As the Earth spins, a spot in day time will
turn away from the Sun and cross into night.
Draw a diagram that shows the relative positions of the Sun, Earth, and Moon during a Lunar Eclipse.
Draw a diagram that shows the relative positions of the Sun, Earth, and Moon during a Solar Eclipse.
Why don’t Eclipses happen every time there is a Full or New Moon?
The plane of the orbit of the Moon around the Earth is not always the same as the plane of the orbit of the Earth around
the Sun. The plane of the orbit of the Moon around the Earth wobbles up and down. When it is tilted at all, when we get
to New or Full Moon the Moon is either above or below the line of the Earth and Sun. And if it isn’t right in line, there
won’t be an Eclipse.
D
What is the relationship between the masses of two objects and the force of gravity between them?
The larger the masses of the objects, the greater the gravity between them. Gravity is “caused” by mass.
What is the relationship between the distance between two objects and the force of gravity between them?
The closer they are together, the greater the gravity between them. It’s kind of like with magnets. The closer together
they are, the harder they pull.
An object in orbit around another object is falling toward it. It just keeps moving forward at the right speed so that it
falls around it, rather than into it. But what would happen to the orbiting object if gravity suddenly disappeared?
What would happen if gravity increased or decreased?
As the force of attraction increases, the orbiting object will move into a lower orbit and speed up. As it decreases, it
would do the opposite. If gravity were to suddenly vanish the orbiting object would stop “falling” and it would keep
moving in the direction it was going when gravity vanished.
E
What could be described as “made up of” galaxies?
The Universe is made up of galaxies.
What could be described as “made up of” stars?
Galaxies are made up of stars.
What could be described as “made up of” planets?
Solar Systems are made up of planets orbiting a central star.
About how many stars are in a galaxy?
100 Billion
About how many galaxies are in the Universe?
100 Billion
How far apart are stars from each other compared to how far planets are from their star?
Stars are at least 10,000 times further apart from one another than the distance between a star and its orbiting planets.