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Describe the theory of how the solar system formed?
A collapsing interstellar cloud of hydrogen forms a
star when the temperature and pressure become
high enough to fuse hydrogen into helium. The
remaining part of the cloud surrounding the star
became the rest of the solar system.
1. List the 6 things that happen to the cloud when it
begins to collapse under its own gravitational pull.
1. Rotates
2.
3.
4.
5.
6.
Accelerates
Contracts
Density increases
Pressure increases
Temperature increases
What happens to the density of the cloud
as it collapses to form a star?
The density increases.
Were the temperatures throughout the
interstellar cloud the same?
No, it was warmer towards the center.
Why did different elements form around the cloud?
Different elements form at different temperatures,
much like Bowen’s reaction series where different
minerals and rocks form at different temperatures.
What do we call the smaller bodies that collided
to make the planets?
Planetesimals
How many planetesimals were there?
100s of them.
What does it mean to be a Terrestrial
planet?
An inner rocky planet
Why don’t we have gas giants near the
Sun?
The gases vaporized
What is the Main Belt and where is it located?
Asteroid belt between Mars and Jupiter.
What is the Kuiper belt and where is it located?
Asteroid belt between located just after Neptune in
Plutos orbit.
What is the Oort Cloud and where is it located?
A large sphere of comets that surround the solar
system and is just after the Kuiper belt.
Describe the direction and speed of the
Sun’s apparent motion in our sky?
15 degrees per hour east to west
Why are impact craters more obvious on
the Moon and Mercury compared to Earth?
They have little to know atmosphere to
weather away the craters.
What is the term for when the Earth closest
to the Sun and when does this occur?
Perihelion
December 21-23
What is the term for when the Earth
farthest from the Sun?
Aphelion
June 21-23
What line of latitude are you at if you
see the Sun directly overhead on the
summer solstice?
The Tropic of Cancer or 23.5 degrees north.
What line of latitude are you at if you
see the Sun directly overhead on the
winter solstice?
The Tropic of Capricorn or 23.5 degrees south.
What line of latitude are you at if you
see the Sun directly overhead on the
equinox?
Equator
What is the term for when the Moon’s
orbital and rotational periods are equal?
Synchronous rotation
What is the term for an Earth centered
universe?
Geocentric
This is the term for the Sun centered solar
system.
Heliocentric
What are the problems with the
Geocentric model?
Could not easily explain observations such as the:
1. Wandering planets (epicycle orbits) and
retrograde motion of the planets
2. Speed of stars would be immense
What is the term for the apparent motion
of the planets that makes them appear to
move backwards because the Earth is on
the “inside track” and passes other planets
which are on more distant orbit?
Retrograde Motion
Which Greek astronomer/mathematician
first came up with the idea of a Sun
centered solar system thousands of years
ago?
Aristarchus
Which Greek astronomer
first came up with the idea of an Earth
centered solar system thousands of years
ago?
Aristotle
Which Greek astronomer
popularized the idea of an Earth centered
solar system thousands of years ago?
Ptolemy
Which scientist is famous for
reintroducing the idea of a Sun
centered solar system in the 1500s?
Nicholas Copernicus
Which scientist first used a telescope to
view the night time sky and collected
evidence to support the heliocentric model
during the Renaissance?
Galileo
What happened to Galileo as a result of
saying the Sun was the center?
He was placed under house arrest for the
remainder of his life.
What evidence did Galileo find to support
the theory that the Sun was the center?
1. Jupiter has its own moons (so not
everything revolves around the Earth).
2. Moon has craters (heavens not perfect)
3. Sun has spots (blemishes) and rotates
According to Kepler’s first law, what is the
true shape of the planetary orbits?
Ellipses
What are the two points in an ellipse
called?
The Foci or focus points
What is the term for the line
that runs through the foci?
The major axis
According to Kepler’s second law, an equal
area is sweep out in
?
equal time
What is the eccentricity of a
straight line?
1
What is the eccentricity of a
Circle?
0
List two of the contributions of Isaac
Newton to Astronomy?
1. Who first quantified gravity
2. Establishes relationship of tides to Moon
3. Creates calculus (Algebraic short cut)
4. Explains math problems with orbits
When does the planet Earth move the
fastest in its orbit?
When it is closest to the Sun on Dec
21-23
Where is the center of mass between
two objects of equal weight?
Half way between them (or in the middle)
Where is the center of mass between
two objects when one mass is larger?
Its closer to the larger mass
If you double the distance between
two objects what happens to the force
of gravity between them?
(Give a numerical relationship)
It is
th
1/4
as great
If you triple the distance between two
objects what happens to the force of
gravity between them?
(Give a numerical relationship)
It is
th
1/9
as great
If you quadruple the distance between
two objects what happens to the force
of gravity between them?
(Give a numerical relationship)
It is
th
1/16
as great
If you halve the distance between two
objects what happens to the force of
gravity between them?
(Give a numerical relationship)
It is 4 times as great
All values for eccentricity lie between
what two numbers?
0 and 1
What is the formula for eccentricity?
Dist between foci
Length of major axis
What is an AU?
It is the average distance from the Earth to
the Sun (1.49 X 10^8 km) or approximately 93 million
miles.
What are the Terrestrial Planets?
The planets that are close to
Earth’s size and have a solid rocky surface.
What are the Gas giants?
Are the large and gaseous planets
which lack a solid surface.
What planet is closest to the Sun and
revolves around the Sun the fastest
(hence its name). ?
Mercury
Why would an impact crater last so
long on Mercury?
There is little atmosphere so there is no weathering
and erosion processes
What does current theory state
created the large scarps on Mercury?
The crust shrinking as the planet cooled.
What is the composition of Mercurys
core?
Iron and Nickel
Which planet has vast amounts of liquid
water on its surface?
Earth!!!!!!!!!!
Which planet is named after the goddess of
love?
Venus
Which planet is the “third rock
from the Sun”?
Earth
Which planet is named after the messenger
god Hermes?
Mercury
Which planet is named after the king of the
gods Zeus?
Jupiter
Which planet is named after the god of
agriculture and time, and is also the father
of Zeus?
Saturn
Which planet has strongly defined belts
and zones, as well as the storm called The
Great Red Spot ?
Jupiter
Which planet has Olympus Mons, the
largest mountain in the Solar System?
Mars
Which planet is named after the god of
the oceans Poseidon?
Neptune
Which planet has liquid metallic hydrogen
as part of its atmospheric composition?
Jupiter
Which planet has a thick atmosphere
composed of mainly CO2 , has a strong
green house effect and is the hottest in the
solar system?
Venus
Which planet spins the fastest
on is axis (fastest day)?
Jupiter
Which planets have a blue color due to the
methane that is in the atmosphere?
Uranus and Neptune
Which planet has retrograde rotation and
has a surface too hot for liquid water to
form?
Venus
Describe the belts and zones?
Belts: low level dark colored warm clouds 
cools and sinks.
Zones: high level, light colored (more ammonia
ice) cool clouds that get warm and rise.
Which planet spins so slowly that one
of its days is longer than its year?
Venus
What created Olympus Mons?
A hot spot
Which planets rocks could have been shot
into space while carrying bacteria to Earth?
Mars
Which planet was predicted before it
was found?
Neptune
What is the name of the storm on Jupiter
that could fit 3 Earths in it and has lasted
over 400 years?
The Great Red Spot
Which planet (besides Earth) shows
evidence of once having water such as
dried lake beds and runoff channels?
Mars
What likely caused the retro rotation of
Venus as well as the near orbital plane
axis of Uranus?
A large collision
Which planets temperature is -215
degrees C, has 27 moons and dark
nearly invisible rings?
Uranus
Which planet is named after the god of
the sky and is the grandfather of Zeus?
Uranus
What planet has the surface feature
called Valles Marineris?
Mars
What is most of the ice on Mars
composed of?
CO2 or dry ice
Which planet had the four moons that
Galileo discovered with a telescope?
Jupitor
Which planet has a red surface and is
named after the god of war Aries?
Mars
Which planet is tipped over to the
point where the north pole is nearly on
its orbital plane?
Uranus
What are the names of the four
Galilean moons and which might have
an ocean of water under the surface?
Io, Europa, Ganymede and Callisto
Europa might have the ocean.
Which planet has signs of intelligent life?
Earth
Which planet is the hottest with
temperatures at 464 degrees C?
Venus
Which planet was discovered in 1781 when
a bluish object was seen moving relative to
the stars?
Uranus
What is the Roman name for the Greek
God of war Aries?
Mars
Which planet represents the counter
part to the Greek god Poseidon?
Neptune
What dilemma did the International
Astronomical Union face when they
discovered Eris which is a body larger than
Pluto?
Should it be called a planet?
What did the IAU reclassify Pluto as?
A dwarf planet
The “left-overs” from the
formation of our solar system
became which bodies that also
orbit the Sun?
The Asteroids and comets
True or false, asteroids can have their
own natural satellites (moons)
True
Explain the difference between a
Meteoroid, a meteor, and a meteorite.
-Meteoroid: Asteroid that enters the Earths
atmosphere.
-Meteor: The streak of light produced by a particle
as it burns up in the atmosphere.
Meteorite: If a meteoroid does not completely burn
up and hits the ground.
What is the largest known asteroid that
is found in the Main Belt
Ceres
Where is the Main Belt located?
Between Mars and Jupiter
What is the main problem with shooting a
missile at a large Comet heading towards
the Earth?
It could have a shot gun effect and hit the Earth in
multiple locations.
What is a comet and where are they
found?
It could have a shot gun effect and hit the Earth in
Small icy bodies (1-10 km in diameter) that have
highly eccentric orbits around the Sun. They are
largely found in the area from the Kuiper belt out to
100,000 AU. This is known as the Oort cloud. Some
get bumped into the inner solar system.
What is a periodic comet?
When a comets orbit takes it close to the Sun, then
leaves and returns to the inner solar system after as
set number of years making it predictable.
What is it called when the Earth crosses the
trail of a comet, the particles burn in the
atmosphere and produces bright streaks of
light?
Meteor Shower
How are meteor showers named?
By the area in the sky in front of the constellation
they appear to come from.
What is the Kuiper belt and where is it
located?
Asteroid belt (bodies made of rocks and ice) that lie
beyond the orbit of Neptune (KBOs).
The early form of the planets which
were colliding solid bodies are called?
Planetesimals
Which planet is closest in size and
mass to the Earth?
Venus
Which planet has about half of Earth’s
diameter?
Mars
Which planet would have the longest
seasons?
Neptune
Which planets diameter is over 11
times larger than Earth’s?
Jupiter
Which planet is closest to Earth in
terms of density?
Mercury
Which two planets have the same
density?
Jupiter and Uranus
Which planet could float in water?
Saturn
Which is more dense, the Sun or the
Moon?
The Moon
Which planet has the most circular
orbit?
Venus
Which planet has the most eccentric
orbit?
Mercury
Which planet has an orbit with the
eccentricity of 0.017?
Earth
What is the relationship between a planets
distance and the eccentricity of its orbit?
There is no relationship
How long is a season on Urans?
21 years
(84 years revolution divided by 4)
How long is a season on Neptune?
41.2 years
(164.8 years revolution divided by 4)