Exam #2
Which of the following lists the planets of our solar system in the correct order from closest to farthest from the Sun?
Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Nept
Which of the following statements about our Sun is
not true?
The Sun's diameter is about 5 times that of Earth.
What are true statement about mars?
The planet in our solar system with the highest
average surface temperature is _________.
Venus
Suppose you view the solar system from high above Earth's
North Pole. Which of the following statements about planetary orbits
will be true?
All the planets orbit counterclockwise around the Sun.
The terrestrial planets in our solar system are _________.
Mercury, Venus, Earth, and Mars.
When we say that jovian planets contain significant amounts of hydrogen compounds, we mean all the following chemicals except _________.
Carbon Dioxide
In essence, the nebular theory holds that _________.
our solar system formed from the collapse of an interstellar cloud of gas and dust
Which of the following is True about the Sun?
The Sun's diameter is more like 100 times that of Earth. That is, Earth is smaller than a typical sunspot.
What is Venus's extreme temperature caused by?
Its very strong greenhouse effect.
Do all planet's except Uranus orbit the sun counter clockwise?
No, Uranus rotates on its side, but there is nothing particularly unusual about its orbit.
When we say that jovian planets contain significant amounts of hydrogen compounds, we mean all the following chemicals except _________.
A) ammonia
B) water
C) methane
D) carbon dioxide
This cloud of gas and dust that gave birth to our solar system is called the
solar nebula.
According to modern science, what was the approximate chemical
composition of the solar nebula?
98% hydrogen and helium, 2% everything else
The terrestrial planets are made almost entirely of elements heavier than hydrogen and helium. According to modern science, where did the elements heavier than hydrogen and helium come from?
They were produced by stars that lived and died before our
solar system was born.
Which of the following types of material can condense into
what we call ice at low temperatures?
Hydrogen compounds
Which chemical elements can condense at low temperatures?
Hydrogen compounds such as water, ammonia, and methane are
gaseous at high temperature but condense into ice at low temperature.
According to our present theory of solar system formation, which of the following lists the major ingredients of the solar nebula in order from the most abundant to the least abundant?
hydrogen and helium gas; hydrogen compounds; rock; metal
What do we mean by the frost line when we discuss the
formation of planets in the solar nebula?
It is a circle at a particular distance from the Sun, beyond
which the temperature was low enough for ices to condense.
What do we mean by accretion in the context of planet formation?
The growth of planetesimals from smaller solid particles that
collided and stuck together
According to our theory of solar system formation, what are
asteroids and comets?
Leftover planetesimals that never accreted into planets
Asteroids are ?
The rocky leftovers of the inner solar system.
Comets are?
The icy leftovers of the outer solar system.
What do we mean by the period of heavy bombardment in
the context of the history of our solar system?
The first few hundred million years after the planets formed, which is when most impact craters were formed
What is the giant impact hypothesis for the origin of
the Moon?
The Moon formed from material blasted out of the Earth's
mantle and crust by the impact of a Mars-size object.
Suppose you start with 1 kilogram of a radioactive substance
that has a half-life of 10 years. Which of the following statements
will be true after 20 years pass?
You'll have 0.25 kilogram of the radioactive substance remaining.
Radio active decay
Isotopes that decay into other nuclei.
Radio active decay half life?
After 10 years, only half of the original kilogram will remain. After 20 years half of that half, or one-quarter of the original amount, will remain.
According to modern scientific dating techniques, approximately how old is the solar system?
4.5 billion years
The sun is how much of Solar systems mass?
98%
The suns temperature
5800 K
Mercury
Venus
Mars
Jupiter
Saturn
Compared to the distance between Earth and Mars, the distance between Jupiter and Saturn is _________.
Much larger
How is Einstein's famous equation, E=mc 2, important in understanding the Sun?
the Sun generates energy to shine by losing 4 million tons of mass each second
E=mc^2
Energy = mass x speed of light squared
In what way is Venus most similar to Earth?
Both planets are the same size
Which of the terrestrial planets has the most extreme seasons?
A) Earth
B)Mars
C) Uranus
D)Jupiter
What is the cause for Uranus's extreme seasons?
Extreme axis tilt
Which of the following is not a major pattern of
motion in the solar system?
Nearly all comets orbit the Sun in same direction and roughly
the same plane.
Which of the following is not a major difference
between the terrestrial and jovian planets in our solar system?
The diameter of Earth's Moon is about 1/4 that of Earth.
According to our theory of solar system formation, which law
best explains why the solar nebula spun faster as it shrank in size?
The law of conservation of energy
According to our present theory of solar system formation,
which of the following best explains why the solar nebula ended up
with a disk shape as it collapsed?
It flattened as a natural consequence of collisions between
particles in the nebula.
What is the primary basis upon which we divide the ingredients of the solar nebula into four categories (hydrogen/helium; hydrogen compound; rock; metal)?
The temperatures at which various materials will condense from
gaseous form to solid form.
According to our present theory of solar system formation, which of the following statements about the growth of terrestrial and jovian planets is not true?
The jovian planets began from planetesimals made only of ice, while the terrestrial planets began from planetesimals made only of rock and metal.
Many meteorites appear to have formed very early in the solar
system's history. How do these meteorites support our theory about
how the terrestrial planets formed?
The meteorites appearance and composition is just what we'd
expect if metal and rock condensed and accreted as our theory suggests.
According to our present theory of solar system formation, how did Earth end up with enough water to make oceans?
As the growing jovian planets captured gas from the solar
nebula, the gas formed swirling disks around them, and moons formed
from condensation accretion within these disks.
Which of the following is not evidence supporting the
idea that our Moon formed as a result of a giant impact?
The Pacific Ocean appears to be a large crater - probably the one made by the giant impact.
Why are terrestrial planets denser than jovian planets?
The terrestrial planets formed in the inner solar nebula,
where only dense materials could condense.
About 2% of our solar nebula consisted of elements besides
hydrogen and helium. However, the very first generation of star
systems in the universe probably consisted only of hydrogen
and helium. Which of the following statements is most likely to have
been true about these first-generation star systems?
There were no comets or asteroids in these first-generation
star systems.
Suppose you find a rock that contains 10 micrograms of
radioactive potassium-40, which has a half-life of 1.25 billion
years. By measuring the amount of its decay product (argon-40)
present in the rock, you conclude that there must have been 80
micrograms of potassium-40 when the rock solidified. How old is the rock?
3.75 billion years
The current 10 micrograms of potassium-40 is 1/8 of the original 80 grams, which means the amount of potassium-40 has declined by a factor of 8. Therefore, three half-lives have passed (since 23 = 8) and the rock is 3×1.25 = 3.75 billion years old.
*first determine fraction of original amount
then determine what factor it is decreasing by
Finally multiply the exponent of the factor x Original half life = age
How do scientists determine the age of the solar system?
Radio metric dating meteorites
Where are Hydrogen compunds found?
Beyond frost line
Name the terrestrial planets by distance from least to greatest from the sun.
Mercury, Venus, Earth, Mars
Name the Jovian planets in distance from least to greatest from Sun.
Jupiter, Saturn, Uranus, Neptune
Explain the Nebular Theory
Explains the formation of the Solar system, which began by the collapse of an interstellar cloud. (Nebula)
Immanuel Kant came up w/ it.
Nebular Theory
All planets lie on same plane due to flattening
Why 2 types of planets?
Jovian planets
Terrestrial Planets
How did the planets form?
Planetismals- tiny particles of our planets came together by Accretion
What is the age of the oldest meteorites dated to ?
4,55 billion years ago