All Material

1. Core 2. Radiative Zone 3. Convective Zone 4. Photosphere 5. Chromosphere 6. Corona 7 Solar Wind

1. It's where the nuclear fusion powering the sun occurs. 2. It's where energy is carried outward by photons & particles from fusion 3. It's where energy is transported outward by swirling gas that has been heated from below. 4. It's the visible surface of the sun. 5. Its red from abundant h-alpha emission and has a temperature from 104-105K 6. It extends millions of miles into space, and has a temperature of 1-2MK 7. Protons, electrons and ions stream away from the sun into space at about 106 mph

Any smaller subsystem (e.g. a planet or a planet and its moons) forming within this disk will tend to form with rotational and orbital motions in the same direction as the solar system. This would apply to... (pick all that apply)

1. rotation of planets on their axes 2. orbit of large moons around planets 3. rotation of moons

As the cloud shrinks, the cloud flattens like whirling pizza dough. Planets are going to form out of this flat rotating cloud. This dynamics directly explains... (pick all that apply)

1. the Sun rotating in same direction as the disk rotation. 2. planets, asteroid and Kuiper Belt objects orbiting in the same direction as the disk rotation 3. planets, asteroid and Kuiper Belt objects orbiting near the ecliptic plane

The graph on the right shows the energy production rate as a function of core temperature. The core temperature of the Sun is about 15MK and thus the CNO process produces only about 1% of the Sun's energy. According to the graph above, at what star core temperature does the CNO cycle become the dominant nuclear reaction?

18MK

What is the scientifically determined age of the solar system?

4.6 billion years

Below are diagrams depicting the Sun, Eath and Mars and the respective orbits of Earth and Mars (in blue). The red dashed line indicates a possible spacecraft trajectories to Mars. Which path best represensts the least-energy trajectory?

A

Two planets, Alice and Bob, have the same radius. Alice has a greater density than Bob. Which has the higher escape velocity?

Alice

Two planets, Bob and Alice, are identical in every way (composition, mass, etc.) except that Bob has a higher atmospheric temperature. Which planet is more likely to have a more substantial atmosphere?

Alice

Why did the solar nebula heat up as it collapsed?

As the cloud shrank, its gravitational potential energy was converted to thermal energy.

Suppose that two fictitious identical planets, Bob and Alice, have the same mass, and size and that both contain atmospheric oxygen. Suppose Alice orbits farther from the Sun than Bob. On which planet would you expect the average speed of oxygen molecules to be higher?

Bob

Shown are graphs of stellar wobbles for three extrasolar planetary systems with identical stars. Assume each host-star has only one planet orbiting. Which stellar wobble shows that it's planet is farthest away from its host-star?

C

Stars make heavier elements out of hydrogen during fusion process in their cores. Just after the beginning of the universe, there was basically only hydrogen (H) and helium (He). The formation of the solar system began as a huge cloud of gas and dust rich in iron, oxygen, silicon, etc. These heavier elements that formed the solar system must have...

Come from previous generations of stars.

Icy leftover planetesimals are what we observe today as

Comets

We can assume that there was no force outside the cloud acting on the cloud. The answer to the previous question is due to angular momentum...

Conservation

Although Mars and Mercury are nearly equal in size, Mars has more of an atmosphere because Mars is

Cooler

Shown below are objects illuminated only by sunlight reflecting off of them. Which of the bodies shown below has the greatest albedo?

D

Two planets, Charlie and Dorthy, have the same density. Charlie has a smaller radius. Which planet has the higher escape velocity?

Dorthy

This huge cloud collapsed to form our solar system. What force caused it to collapse?

Gravity

How does the greenhouse effect work?

Greenhouse gases transmit visible light, allowing it to heat the surface, but then absorb infrared light from the Earth's surface, trapping the heat near the surface

Which of the following is FALSE regarding radiometric dating?

If a radioactive nuclei has a half-life of one thousand years, then it requires one thousand years to measure its half-life

Statistically, there will be some net rotation about some axis. As the cloud slowly collapses inward the rotation rate (Hint: like spinning skater pulling her arms in)...

Increases

According to the Nebular Theory, how did the Oort cloud form?

It is made of planetesimals formed in the outer solar system that were flung into distant orbits by encounters with the Jovian planets.

Which of the following planetary properties listed is the most important factor for a terrestrial planet to have active volcanism or plate tectonics?

Its size and internal temperature

This gas giant planet is the largest in the solar system and is also known for its Great Red Spot

Jupiter

Assuming that the density of planet building material has the same density at both locations, would you expect Jupiter & Saturn or Uranus & Neptune to grow faster?

Jupiter and Saturn

Which planets would you expect to have quickly gain lots of mass, have had more gravity, and thus been more capable of pulling in copious amounts of H and He from the solar nebula?

Jupiter and Saturn

Many of these icy leftovers orbit the same direction as the original planetary nebula (and thus the planets) and are concentrated near the ecliptic plane in the...

Kuiper Belt

This region is beyond the orbit of Neptune and contains icy bodies that orbit counter-clockwise around the Sun. These bodies are concentrated near the ecliptic plane.

Kuiper belt

Jovian planets are very large and have substantial atmospheres. _________ temperatures and __________ escape velocities contribute to that.

Low, High

Mercury is a small planet, not much larger than our Moon and it is close to the Sun (average distance of 0.39AU). The following contribute to Mercury essentially having no atmosphere-its____________ escape velocity and the___________ temperatures.

Low, High

This planet has a reddish appearance, has enormous volcanoes and a long, deep valley that would span the United States. It also has two small moons.

Mars

Two planets, John and Mary, are identical in density and temperature, but Mary is larger in size (radius) than John. Which planet is likely to have a more substantial atmosphere? (Hint: Completing the Atmospheric Retention Exercise first may help.

Mary

A fictitious planet formed containing molecular hydrogen, helium and methane. Which molecules would have the slowest average velocity?

Methane

Which of the following statements is NOT an observed pattern of motion in our solar system?

Most planets orbit at the same speed

This planets is known for hits high winds and bluish appearance due to methane in its atmosphere. It is the farthest "official" planet in the solar system.

Neptune

These icy leftovers orbit may have formed among the giant Jovian planets only to be gravitationally hurled out of the ecliptic plane in randomly-oriented orbits in a region called the..

Oort Cloud

What happened during the accretion phase of the early solar system?

Particles grew by colliding and sticking together

The Earth's moon is much larger and has almost twice the escape velocity as Pluto does. The Moon has basically no atmosphere at all, but Pluto does. This is because...

Pluto is much colder than the Moon and gas particles move much more slowly and less of it is lost.

Mars is the farthest terrestrial planet from the Sun at a distance of 1.5AU. From the information in the graph above, the terrestrial planets formed from...

Rock and Metal only

Jupiter is the closest Jovian planet to the Sun at 5.2AU away. Jovian planets formed from..

Rock, Metal, and Ices

Two identical stars, Tom and Sherry, each have one planet orbiting them, causing them to wobble. Sherry's planet orbits closer to Sherry than Tom's planet orbits around him. Which star, Tom or Sherry, will wobble with a shorter periodicity?

Sherry

If a planet had formed 3.0AU away from the Sun, it would have been which kind of planet?

Terrestrial

The current thinking about how our Moon formed is that a Mars-sized object collided with Earth in with just the right glancing blow that some of the material from the collision collected together in orbit around the Earth. Along with the destroyed impactor, a large portion of the Earth's upper mantle (density 3.3 g/cm3) would have been blasted into space. As a result of the high temperature involved in this collision all the Moon would have formed with large magma oceans with any volatiles evaporating away into space. Moon rocks indeed suggest the presence of these magma oceans and the rocks are extremely deficient in volatiles (they are very dry). Different bodies in the solar system differ in the types and amounts of radioactive isotopes. However, the type and amount of radioactive isotopes found on the Moon are the same as those found on Earth. From the information given above, and data from the table, what other evidence is there in support of the impact theory?

The Moon has about the same average density as Earth's upper mantle.

All the following statements about Earth's atmosphere is true except which one?

The temperature drops uniformly as one ascends up through it into space

From the discussion above, why does fusion occur in the core, as opposed to other layers?

The temperature, pressure and density are highest there.

Which of the following is NOT true of sunspots?

They are static and unchanging.

The emitted positron is the antiparticle of electrons. The core is full of free electrons and the positron will eventually interact with an electron. What will happen when it does?

They will annihilate each other, giving off a pair of gamma rays.

This moon is covered with a thick atmosphere and appears to have rivers and lakes of liquid methane.

Titan

This moon has one of the coldest surfaces in the solar system. It is covered with nitrogen ice and has nitrogen geysers.

Triton

At the end of the formation of the Jovian planets, we are left with gas giants (90% H & He) and ice giants (20% H and He). Which planets are the ice giants?

Uranus and Neptune

If the temperature of a planet were to approach 0 Kelvin, what value would the average velocity approach?

Zero

For a planet to have a strong magnetic field, all of the following are thought to be essential except for which one?

a rocky mantle

Rocky and metallic leftover planetesimals are what we observe today as...

asteroids

These bodies, 50-meters to 400-kilometers in size, are composed of rock and metal. Most of them orbit the Sun between Mars and Jupiter.

asteroids

If an exoplanet is discovered transiting a star and thus being eclipsed by the star when the planet orbits on the "back" side, which of the following is NOT something that can sometimes be measured?

axial tilt of the planet

The average temperature at the Sun's surface (called the photosphere) is about 5800K. According to the trend in temperature graphed above, one would expect the temperature well above the surface to

be less than 5800K

Neptune was discovered..

because of its influence on the orbit of Uranus

Consider two planets, Bob and Carol. Carol has both a lower escape velocity and a higher atmospheric temperature than Bob. Which is more likely to retain hydrogen in its atmosphere?

bob

Which of the following spacecraft was sent as a Saturn obiter?

cassini

These bodies are composed if rock and ice and can occasionally form a coma and tail if they get close to the sun where its ices begin to sublimate.

comets

Which of the following is NOT believed to be a source of heating of the interior of a terrestrial world (planet or moon)?

conduction

Plate tectonics on Earth is believed to be driven by...

convection in the mantle

According to the graphs above, the hottest and densest part of the Sun is at its

core

All of the following surface features may result from tectonics, except for which one?

craters

Pluto is classified as a..

dwarf planet

These bodies orbit the Sun and are large enough that their own gravity forces them into a spherical shape. However, they have not cleared their orbital paths sufficiently to be called planets.

dwarf planets

The main idea behind a spacecraft taking a least-energy trajectory (Hohmann transfer orbit) to a planet is that it.

follows an elliptical orbit, with the Sun at one focus, basically using the gravity of the Sun to accelerate the spacecraft to the planet.

As the cloud shrinks, it gets hotter in the center. This is due to the conversion of...

gravitational potential energy to thermal energy.

According to the above pie chart displaying the Sun's composition, the most abundant substance in the Sun is

hydrogen

The most successful hypothesis about the origin of our Moon is that.

it was created by an impact of a Mars-sized planet and that debris from the impact formed the Moon

Which of the following is NOT a relevant factor that determines the surface temperature of a terrestrial planet?

its interior temperature

This moon has active sulfur and sulfur dioxide volcanoes and is believed to be heated internally by tidal forces from Jupiter

lo

The general cause of sunspots, coronal mass ejections and most surface activity are strong

magnetic fields

These small rocky bodies are often pieces of larger bodies. Many can be found on the Earth's surface.

meteoroids/meteorites

All of the following provide evidence of past impacts on Earth except for which one?

monolithic mountain-sized protrusions of an impactor in otherwise-flat areas

What force prevents the inward pull of gravity from pulling the Sun (ball of gas) inward and collapsing it?

outward radiation pressure from fusion

The large-scale movement of continents on Earth, as shown below, is believed to be due to

plate tectonics

Clyde Tombaugh discovered..

pluto

According to the Nebular Theory, as the cloud the formed our solar system collapsed, the gas particles lost gravitational potential energy and gained an equal amount of kinetic energy. Particles falling all the way to the center gained the most kinetic energy. This resulted in

the Sun forming in the center

Space weather is attributed to (pick all that apply)

the creation of aurorae, the disruption of power grids., interference or distruction of satellites.

Inside the frost line, closer to the Sun, only rock and metal can condense to form a solid. Outside the frost line, farther from the Sun, hydrogen compounds can also condense to form ices. This explains

the existence of terrestrial planets close to the Sun and Jovian planets farther from the Sun

Which of the following is a characteristic of all Jovian planets?

they have ring systems

Which of the following missions flew by all of the Jovian planets?

voyager II

As the solar nebula collapses inward because of its own gravity, it flattens out, with gas and dust going around in the same direction. This explains (choose all answers that apply)

why planets orbit in the same direction. why the Sun rotates in the same direction that planets orbit. why planets orbit in the same plane-near the ecliptic plane