Astronomy Final - Set One

12.4: Which of the following temperatures is closest to what you might expect on the planet Neptune?

-350 F

22.2: Which of the following magnitudes corresponds to the brightest star?

-4.2

22.3: The distance modulus of a star at a distance of 10 parsecs would be

0

8.5: A solar sail is a large sheet of light-reflecting plastic spread on an extremely low-mass framework and attached to a spacecraft. Sunlight exerts a force on the sail and moves the spacecraft. Suppose the spacecraft has a total mass of 2000kg (including the sail) and sunlight exerts a total force of 10N on the sail. What will be the acceleration of the spacecraft?

0.005m/s2

25.2: The mass of a carbon atom is 12.00amu while the mass of a helium-4 atom is 4.003amu. If three atoms of helium fuse to form carbon, how much mass is converted into energy?

0.009 amu

15.1: The the Earth's atmosphere, the percentage that is water vapor is roughly

1%

10.1: The average radius of the Earth's orbit is

1.0 au

22.1: Cruising far from the Sun, we notice that the Sun's apparent brightness has dimmed to 10 watts per square meter. We know that the apparent brightness at a distance of 1au is 1000 watts per square meter. How far from the Sun are we?

10 au

12.1: Compared to the Earth, the planet Jupiter is roughly

10 times as large

29.3: The diameter of the Milky Way Galaxy is close to

100,000 light years

22.4: A star is found to have absolute magnitude 4 and apparent magnitude 24. How far away is it?

100,000 parsecs

10.3: The density of water is 1000kg/m3, the density of rock is about 3000kg/m3, and the density of iron is 7800kg/m3. Which of the following densities would indicate an object that consists mostly of substances much less dense than rock or iron?

1000kg/m3

3.3: At 8pm, you see that the pointer stars of the Big Dipper and the star Polaris are arranged in a vertical line. At what time, give or take a minute or so, would you see them arranged at 45 degrees to the vertical?

11:00pm the same day

21.1: The velocity of sound waves is roughly the same for all wavelengths. Suppose that a sound wave has a wavelength of one meter and a frequency of 1000Hz. The wavelength of a 500Hz sound wave would then be

2 m

20.4: Barnard's Star shows a heliocentric stellar parallax near 1/2 seconds of arc. The distance from our Sun to Barnard's Star is

2 parsecs

20.4: The star pi3-Orionis is 8 parsecs from our Sun. The light from pi3-Orionis has been traveling for

26.4 years

7.5: The length of a sidereal month is 27 days. The time from one full Moon to the next is closest to

29.5 days

21.2: The violet lines in the Hydrogen spectrum are normally seen with wavelengths 410nm and 434nm. In the light of a star that is moving toward us, we might expect to see those lines at wavelengths of

400nm and 424nm

8.5: What total force will cause an object with a mass of 10kg to gain 5 meters per second every second?

50 Newtons

11.4: A lunar crater is best described as

A circular ring wall surrounding a flat area

10.3: 3 It is expected that a normal Jovian planet, with no accidental encounters that could add or subtract moons, should have

A family of moons, all orbiting in the plane of the planets equator

17.2: An encounter between Earth and an iron asteroid fifty meters in diameter would most likely cause

A large explosion on the ground

13.2: When the Earth passes through the orbit of a broken-up comet, we see

A meteor shower

3.1: The time it takes for the Celestial sphere to rotate once relative to the Earth is called

A sidereal day

26.4: A planetary nebula forms when

A star becomes a white dwarf

18.4: An example of a life form that does not get its energy originally from the Sun would be

A tube worm near a black smoker

7.5: Just before sunrise, you might find

A waning crescent Moon rising in the east

5.2: In addition to being accurate, Tycho Brahe's observations focused on measuring the positions of the planets

All the time

7.1: Which object is most likely to be considered a scientific model?

An accurate map of Richmond

5.5: Kepler's First Law of Planetary Motion is that the orbit of each planet is

An ellipse with the Sun at one focus

16.1: Underneath the Atlantic Ocean is an undersea mountain range called the MidAtlantic Ridge. The ridge is caused by

An upward current in the Earth's Mantel

11.4: The first human landing on the Moon was

Apollo 11 in 1969

9.4: Kepler's Laws

Are explained by a force that attracts each planet to the Sun

8.4: Suppose that you drop two objects from the same height at the same time. Both objects are heavy enough to be unaffected by air resistance and one object is twice as heavy. Who predicted that the heavier object would hit the ground long before the lighter one?

Aristotle

25.3: Because of the electrical repulsion between atomic nuclei, nuclear fusion happens only

At high temperatures

24.1: In the Hertzsprung-Russell diagram, point 4 at magnitude B and +10 could be a

B0 star of absolute magnitude 10

1.1: The newspaper says that the Moon was full last night. That statement is most likely

Based on some authoritative reference such as the U.S. Naval Observatory

13.3: The objects of the Kuiper belt are mostly orbiting

Beyond all of the Jovian planets

14.4: The Tau-Tauri wind from the Sun's final collapse toward ignition

Blew away the fuel that Jupiter needed to become a star

17.3: A large asteroid impact can affect the Earth's climate primarily by

Blocking the sunlight with its smoke and dust

29.5: The source that is called Sgr A* emits

Both infrared light and radio waves

11.3: Milankovich cycles refer to

Changes in the intensity of sunlight due to shifts in both the Earth's orbit and rotation axis

4.2: The Ptolemaic model of the Solar System has each planet moving along a

Circular epicycle whose center, in turn, moves around the Earth

18.5: A pair of sugar phosphate chains connected by pairs of nitrogenous bases describes a molecule of

DNA

25.5: A brown dwarf shines primarily with

Energy left over from its formation

11.4: The magnetic field of Earth's Moon is

Essentially zero

19.3: Which of these moons has patterns of cracks in the ice on its surface indicating a subsurface ocean?

Europa

4.3: One objection to a solar system model that has the Earth moving around the Sun is that we would then see nearby stars seem to shift back and forth relative to more distant stars. The correct answer to that objection is that

Even the closest stars are so far away that the shift is very small

28.3: The point at which even an outwardly directed light ray is pulled into a black hole is called the

Event horizon

23.3: Which of the following spectral types corresponds to the star with the highest surface temperature?

F0

6.1: True or False: All of the fish in Lake Nyak are green

False

9.6: Suppose that the Space Shuttle is in a roughly circular orbit near the surface of the Earth, moving at around 5 miles per second. Suppose the Space Shuttle tips over backwards and fires its rocket engine to slow its speed to 4.96 miles per second. The shuttle will then

Follow an ellipse that descends a bit and then rises again

27.4: Supernova explosions tend to

Form elements heavier than iron

16.3: Carbon is essential for all life we know about because it

Forms complex compounds

24.4: Which of the following spectral types corresponds to a star on the main sequence?

G2V

20.3: To measure the heliocentric stellar parallax of a star, you mostly need a telescope with

High resolving power

18.3: The molecules of both water, ice, and liquid water are attached to one another by

Hydrogen bonds - different parts of each molecule have opposite charges

13.4: Sedna is thought to be

In the Inner Oort Cloud

12.2: The rotation axis of Saturn is

Inclined at an angle to the perpendicular that is similar to Earth's rotation axis

15.5: The part of a protostar where the density first becomes low enough for light to escape is called the

Inner core

19.5: The range of signal frequencies between absorption bands caused by hydrogen and hydroxyl molecules

Is referred to as the "water hole" and is the frequency band that SETI programs usually choose

14.5: According to the current definition of a planet, Pluto is not regarded as a planet because

It has not cleared its neighborhood of other orbiting objects

19.4: One requirement for a planet to support Earth-type life is that it considerably larger than Mars. What is the reason for this requirement?

It is necessary for the planet to have active plate tectonics to close its carbon cycle

28.1: The reason that the Crab Pulsar is slowing down is

Its magnetic field is dragging through nearby gas

1.2: Joseph Weber designed a series of devices to detect ripples in space-time, called gravitational waves. After several years of effort, Joe announced that he had detected gravitational waves. He built several versions of his devices and they all detected the waves. When other people tried to build similar devices, none of them detected anything at all. Joe's evidence was ignored by the scientific community because

Joe's observations were not reproduced by others

12.1: Pioneer 10 was an early space probe sent to fly past

Jupiter

8.5: The Law of Inertia states that a moving object will

Keep moving if no force acts on it

11.2: The Russian Venera 9 space probe was sent to Venus, where it

Landed on the surface and took pictures

7.3: Aristarchus measured the angle between the Sun and the Moon when exactly half of the Moon was illuminated. If the Sun were actually just two or three times as far away as the Moon, he would have found that angle to be

Less than 90 degrees by an amount that was easy for him to measure

19.4: The eclipse or transit photometry method of searching for exoplanets can be expected to find

Less than one out of every 10 exoplanets

11.1: The second space probe to reach the planet Mercury was

MESSENGER

11.5: Which object has no overall magnetic field except for small regions due to magnetized ore deposits?

Mars

16.5: An example of a planet which may occasionally have liquid water but retains an atmosphere of mostly carbon dioxide is

Mars

10.4: The Asteroid Belt is between the orbits of

Mars and Jupiter

19.2: Which statement best describes the presence of water on Mars?

Mars probably had liquid water flowing on its surface at some time in the past

29.5: The motions of the stars near Sgr A* make it possible to determine its

Mass

28.4: The X-rays that reveal the possible presence of a black hole are the result of

Matter heating up as it falls toward the hole

11.1: The angle between the rotation axis of a planet and the perpendicular to the plane of its orbit is called its "axial tilt." Which planet has an axial tilt that is less than one degree?

Mercury

12.2: The temperature of Saturn is

Much colder than anywhere on Earth

27.4: The gravitational energy that is released when the core of a massive star collapses is usually

Much larger than the nuclear energy that the star has generated

12.2: The main ingredient in the atmosphere of Titan is

Nitrogen

7.6: The patent for inventing the telescope was obtained by

Nobody because it was too simple an idea to patent

12.2: Which space probe flew past Saturn but not past Jupiter?

None

18.2: Carbon is

One of the four most common elements in the universe

17.4: Suppose that an asteroid, about 1 kilometer in diameter, shows a 1 in 100 probability of an Earth impact fifty years in the future. Assume that an impact will trigger climate changes that would kill one billion (1,000,000,000) people. Also assume that each of these deaths represents $100,000 in lost production. Using the cold economic logic that we discussed in class, how much money should be budgeted to deflect the asteroid?

One trillion dollars ($1,000,000,000,000)

14.2: The part of a protostar where the density first becomes low enough for light to escape is called the

Photosphere

24.1: In the Hertzsprung-Russell Diagram shown, which point represents a star of type B with absolute magnitude -5?

Point that aligns with 'B' and -5

14.4: It has been theorized that planets do not easily form in binary star systems. If they do form, there are three possible arrangements: (1) Planets with orbits similar in radius to the distance between the two stars. (2) Planets with orbits much smaller in radius than the distance between the two stars. (3) Planets with orbits much larger in radius than the distance between the two stars. Observations so far (2009) indicate that

Possibilities (2) and (3) actually happen

25.1: Which of the following particles would be attracted to a neutron through the strong force?

Protons

18.5: The role of the DNA molecule in current Earth life is to

Provide the patterns for the enzymes that carry out the chemical processes of life

26.2: When a red giant star begins to burn helium, it

Returns part way to the main sequence in an HR diagram

29.1: The thickest part of the visible Milky Way is near the constellation

Sagittarius

6.4: The idea that science only deals with statements that are falsifiable subject to possible disproof by observation, suggests that

Science produces revisable facts

3.3: As seen from North America, the constellation Orion

Sets in the west and southwest

15.2: Colder air always

Sinks

11.5: A full cycle of day and night on Mars is called a 'sol.' In terms of 24 hour Earth days, a Martian sol is

Slightly longer than one Earth day

19.4: Planets that are in orbit around stars other than our own Sun are most often found by observing

Small changes in starlight due to planetary transits

18.4: The chlorophyll in plants uses sunlight to

Split water into hydrogen and oxygen

22.5: Consider a light source whose absolute magnitude can be deduced from the properties of the light that reaches us from that source. Astronomers often refer to this sort of object as a

Standard candle

7.4: In the picture that we used in class, with the Sun above the top of the picture and the Earth shown with its North Pole facing you, the part of the Earth that is to the right of the North Pole in the picture is experiencing

Sunrise

15.4: The term 'greenhouse effect' refers to

The absorption of infrared light by gases in the atmosphere

25.4: During the Tau Tauri phase of a protostar's evolution,

The brightness decreases

11.4: The capture theory, in which our Moon forms separately and is captured by the Earth, enjoyed a brief popularity when computer models showed that such a capture would have been possible.

The capture theory was dropped because it predicts that the Moon should have hydrated rocks and it does not

8.3: For an object that is moving along a straight path, the acceleration is

The change in the object's speed divided by the time it takes

16.1: Consider a planet that is similar to Earth in size and Mass with a semiliquid interior. According to our current understanding, which of the following things is also necessary for that planet to have active plate tectonics?

The core temperature should be much higher than the surface temperature

20.1: A converging lens will send light rays that are parallel to the axis through

The focal point of the lens

8.6: A motorcycle is accelerating from rest. Which of the following pairs of forces is an action-reaction pair?

The force of the motorcycle on the road and the force of the road on the motorcycle

21.1: The frequency of a wave is defined to be

The number of crests that pass in one second

3.5: The ecliptic is

The path of the Sun on the Celestial Sphere

18.1: Compared to the frequency of photons absorbed during a transition from a from a -6ev state to a -4ev state, transitions from the -5ev state to a -3ev state would correspond to absorbing photons whose frequency is

The same

6.3: Einstein's Theory of Relativity has passed every observational test for over 100 years. Cliff has analyzed a large family of alternative theories and figured out what each one predicts for the results of observational tests. Cliff presents his analysis at a scientific meeting. Which of the following would be the most likely reaction of the scientists at the meeting to this new development?

There is great interest because the analysis suggests new tests that could prove that Relativity is wrong, so lots of scientists come to Cliff's talk to congratulate him

11.5: Pathfinder was the first

To use airbags to land on Mars

9.1: A planet that is following Kepler's Laws, accelerates

Toward the sun

21.1: The wavelength of the sound waves that correspond to middle-C is about 4 feet. If you are standing 8 feet away from a piano that is playing that note, then between you and the piano there will usually be

Two regions of maximum pressure

12.3: Voyager 2 is the only space probe so far to have visited

Uranus

11.2: Which of the following planets or moons has an atmosphere with about 90 times the surface pressure of Earth's?

Venus

7.5: Which phase of the Moon would be seen high in the south at dawn?

Waning quarter

2.5: Astronomy is known for claiming to have measured things that cannot possibly be probed directly. These measurements are made by combining actual measurements with

Well-tested models

20.4: The star Wemadeit shows a stellar parallax angle of 0.4 seconds of arc while the star Waytoofar shows a stellar parallax angle of 0.3 seconds of the arc. From this, you can conclude that

Wemade it is closer to our Sun than Waytoofar

1.5: The idea that a worthwhile model of a situation must predict what is actually observed seems to have started

With the ancient Greek philosophers