Universe Midterm 1 Chapters 1-6

Which of the following is not true about a scientific theory? a. A theory is essentially an educated guess. b. Even the strongest theories can never be proved true beyond all doubt. c. A theory must explain a wide range of observations or experiments. d. A theory is stronger than a hypothesis, and weaker than a law.

A. A theory is essentially an educated guess.

Why does Neptune appear blue and Jupiter red?

A. Methane in Neptune's atmosphere absorbs red light.

In winter, Earth's axis points towards the star Polaris. In summer, the axis points towards: a. Polaris. b. Vega. c. some point between Polaris and Vega. d. the Sun.

A. Polaris.

When we say that a planet has a highly eccentric orbit, we mean that: a. in some parts of its orbit it is closer to the Sun. b. it is spiraling in toward the star. c. it is very close to being circular. d. its orbit is an ellipse with the star at one focus.

A. in some parts of its orbit it is closer to the Sun.

Which of the following correctly lists our "cosmic address" from small to large? A. Earth, Solar System, Local Group, Local Supercluster, Milky Way, Universe. B. Earth, Solar System, Milky Way, Local Group, Local Supercluster, Universe C. Earth, Solar System, Local Group, Milky Way, Local Supercluster, Universe. D. Earth, Local Group, Milky Way, Solar System, Local Supercluster, Universe.

B. Earth, Solar System, Milky Way, Local Group, Local Supercluster, Universe

The gravitational potential energy of a contracting interstellar cloud:

B. gradually transforms into other forms of energy.

Two stars that are in the same constellation: a. must be near each other in space. b. may be far from each other in space. c. must have been discovered at about the same time. d. are the same distance from us.

B. may be far from each other in space.

You observe a star and measure a spectral line at a wavelength of 652 nm. Normally, this spectral line should appear at a wavelength of 656 nm. Given this information, the star is:

B. moving towards us.

To make a rocket turn left, you need to: A. spin the rocket clockwise. b. fire an engine that shoots out gas to the left. c. fire an engine that shoots out gas to the right. d. spin the rocket counterclockwise.

C. fire an engine that shoots out gas to the right.

A car is accelerating when it is: a. traveling on a straight, flat road at 20 mph. b. on a ferry cruising at 20 knots. c. going around a circular track at 20 mph. d. traveling on a straight, uphill road at 20 mph.

C. going around a circular track at 20 mph.

The fact that nearly all galaxies are moving away from us, with more distant ones moving faster, helped us to conclude that: a. galaxies repel each other like magnets. b. our galaxy lies near the center of the Universe. c. the Universe is expanding. d. galaxies have dark matter.

C. the Universe is expanding.

The labeled transitions (A—E) represent an electron moving between energy levels in hydrogen. The transition from level 3 to level 2 generates what is known as the H-alpha line and is among the most important lines in astronomy. The photon corresponding to this transition has a wavelength of 656 nm placing it firmly in the red part of the visible spectrum. What is the energy of this photon?

D. 1.9 eV

How many times stronger is the energy of a major earthquake compared with that of a 1-megaton hydrogen bomb?

D. 5

The asteroid belt lies between the orbits of:

D. Mars and Jupiter.

How large an object causes a typical shooting star?

D. a grain of sand or a small pebble

You observe a star and measure a spectral line at a wavelength of 652 nm. Normally, this spectral line should appear at a wavelength of 656 nm. Given this information, the star is:

D. blueshifted.

The set of spectral lines that we see in a star's spectrum depends on the star's:

D. chemical composition.

Which lists the major steps of Solar System formation in the correct order?

D. collapse, condensation, accretion

Compared to red light, blue light has higher frequency and:

D. higher energy and shorter wavelength.

The composition of the Solar nebula was 98%:

D. hydrogen and helium.

Some jovian planets give off more energy than they receive because of:

D. ongoing contraction.

The star Betelgeuse is about 600 light-years away. If it explodes tonight: a. none of the above. b. we'll know because debris from the explosion will rain down on us from space. c. we'll know it immediately because it will be brighter than the full Moon. d. we won't know about it until 600 years from now.

D. we won't know about it until 600 years from now.

Suppose you visit the Moon: a. your mass and weight would be the same as they are on Earth. b. your weight would be the same as on Earth, but your mass would be different. c. your mass and weight would be different than they are on Earth. d. your mass would be the same as on Earth, but your weight would be different.

D. your mass would be the same as on Earth, but your weight would be different.

Which kind of star is most likely to be part of the spheroidal population of a galaxy? A star O star M star G star

M star

Why do virtually all the galaxies in the Universe appear to be moving away from our own? a. Because expansion causes all galaxies to move away from nearly all others. b. Because we are located near the center of the universe. c. Because we are located near where the Big Bang happened. d. Because gravity from outside the Universe is pulling everything apart.

a. Because expansion causes all galaxies to move away from nearly all others.

Which of these options is the best explanation for why the night sky is dark? a. The Universe is not infinite in space. b. The Universe has not always looked the way it looks today. c. The distribution of matter in the Universe is not uniform on very large scales. d. Starlight from distant stars has not reached us yet.

a. The Universe is not infinite in space.

Which of the following possible types of universe would not expand forever? a. a recollapsing universe b. an accelerating universe c. a critical universe d. a coasting universe

a. a recollapsing universe

Which kind of object is the best standard candle for measuring distances to extremely distant galaxies? a. a white dwarf supernova b. a supermassive black hole c. a white dwarf d. a Cepheid variable star

a. a white dwarf supernova

Which of these galaxies would you most likely find at the center of a large cluster of galaxies? a. an elliptical galaxy. b. a spiral galaxy c. a lenticular galaxy d. an irregular galaxy

a. an elliptical galaxy.

At the center of the Sun, fusion converts hydrogen into: a. helium, photons, and neutrinos b. plasma c. photons d. helium, carbon, and oxygen

a. helium, photons, and neutrinos

Solar energy leaves the core of the Sun in the form of: a. photons. b. rising hot gas. c. sound waves. d. helium.

a. photons.

Based on current evidence, which is considered a likely candidate for the majority of the dark matter in galaxies? a. subatomic particles that we have not yet detected b. supermassive black holes c. swarms of dim, red stars d. a huge population of hidden brown dwarfs

a. subatomic particles that we have not yet detected

We measure the mass of the black hole at the galactic center from: a. the orbits of stars in the galactic center. b. the jets that emanate from the black hole. c. the orbits of gas clouds in the galactic center. d. the amount of radiation coming from the galactic center.

a. the orbits of stars in the galactic center.

What pieces of information would you need in order to measure the masses of stars in an eclipsing binary system? a. the time between eclipses and the average distance between the stars b. the brightness of the stars and and their distance from the Sun c. the velocities of the stars and the Doppler shifts of their absorption lines d. the period of the binary system and its distance from the Sun

a. the time between eclipses and the average distance between the stars

Why do sunspots appear darker than their surroundings? a. They do not emit any light. b They are cooler than their surroundings. c. They are composed of dark matter. d. They block some of the sunlight from the photosphere.

b They are cooler than their surroundings.

Which of these binary systems is most likely to contain a black hole? a. A binary containing a K star and another object of equal mass. b. A binary containing an O star and another object of equal mass. c. A binary containing a supergiant star and a white dwarf. d. A binary containing an X-ray pulsar.

b. A binary containing an O star and another object of equal mass.

Which of these pieces of evidence supports the idea that inflation really happened? a. The fact that distant galaxies are moving away from us. b. Observations of the cosmic microwave background that indicate large-scale homogeneity in the Universe. c. The enormous size of the observable Universe. d. The large amount of dark matter that the Universe contains.

b. Observations of the cosmic microwave background that indicate large-scale homogeneity in the Universe.

Which of the following does inflation help to explain? a. The temperature of stars. b. The uniformity of the cosmic microwave background. c. The number of stars in the Universe. d. The amount of dark matter in the universe.

b. The uniformity of the cosmic microwave background.

A photograph of a cluster of galaxies shows distorted images of galaxies that lie behind it at greater distances. This is an example of what astronomers call: a. spiral density waves. b. a gravitational lens. c. dark energy. d. inflation.

b. a gravitational lens.

To explain the fact of evolution, we rely on the theory of natural selection which is: a. just a guess about how life changes through time. b. a scientific theory, meaning that it is backed by extensive evidence. c. questionable. d. one of several competing scientific models that all seem equally valid

b. a scientific theory, meaning that it is backed by extensive evidence.

A brown dwarf is: a. a white dwarf that has cooled off. b. an object not quite massive enough to be a star. c. a star-like object that is less massive than Jupiter. d. the final stage of the life sequence of a low-mass star.

b. an object not quite massive enough to be a star.

What do we need to measure in order to determine a star's luminosity? a. mass and distance b. apparent brightness and distance c. apparent brightness and temperature d. mass and temperature

b. apparent brightness and distance

What causes the cycle of Solar activity? a. changes in the Sun's fusion rate b. changes in the organization of the Sun's magnetic field c. changes in the speed of the Solar wind d. rotation of the Sun

b. changes in the organization of the Sun's magnetic field

Where do gamma-ray bursts tend to come from? a. black holes in our galaxy b. extremely distant galaxies c. relatively nearby galaxies d. neutron stars in our galaxy

b. extremely distant galaxies

The primary source of a quasar's energy is: a. nuclear energy. b. gravitational potential energy. c. electromagnetic energy. d. chemical energy.

b. gravitational potential energy.

Where are most of the Milky Way's globular clusters found? a. in the center b. in the halo c. in the bulge d. in the disk

b. in the halo

According to current understanding, the key requirement for life is: a. oxygen. b. liquid water. c. photosynthesis. d. an atmosphere.

b. liquid water.

Which of these layers of the Sun is coolest? a. ionosphere b. photosphere c. corona d. chromosphere

b. photosphere

What is the current temperature of the Universe? a. a few hundred degrees b. absolute zero c. a few degrees d. a few thousand degrees

c. a few degrees

Which of these stars does not have fusion occurring in its core? a. a red main-sequence star b. a blue main-sequence star c. a red giant d. a Sun-like star

c. a red giant

Stars can form most easily in clouds that are: a. hot and low-density. b. hot and dense. c. cold and dense. d. warm and dense.

c. cold and dense.

Anabolism refers to chemical reactions that: a. break down structures. b. maintain a constant level of chemicals. c. grow larger structures. d. transfer genetic information.

c. grow larger structures.

How does the habitable zone around a star of spectral type G compare to that of a star of spectral type M? a. it is hotter b. it is colder c. it is larger d. it is smaller

c. it is larger

Homeostasis refers to chemical reactions that: a. break down structures. b. grow larger structures. c. maintain a constant level of chemicals. d. transfer genetic information.

c. maintain a constant level of chemicals.

Dark matter is inferred to exist because: a. it is needed to trigger fusion reactions in the Sun. b. it explains how the expansion of the universe can be accelerating. c. we can observe its gravitational influence on visible matter and on light. d. we see lots of dark patches in the sky.

c. we can observe its gravitational influence on visible matter and on light.

Fossil evidence suggests that life arose on Earth: a. within the last several thousand years. b. about a billion years after Earth formed. c. within a few hundred million years after Earth formed. d. about a billion years before the rise of the dinosaurs.

c. within a few hundred million years after Earth formed.

What would happen to a neutron star whose accretion disk orbits in the same direction as the neutron star's spin? a. Its spin would begin to wobble (precession). b. Its spin would stay the same. c. Its spin would slow down. d. Its spin would speed up.

d. Its spin would speed up.

Which lists the jovian planets in order of increasing distance from the Sun? a. Saturn, Jupiter, Uranus, Neptune b. Saturn, Jupiter, Neptune, Uranus c. Jupiter, Saturn, Neptune, Uranus d. Jupiter, Saturn, Uranus, Neptune

d. Jupiter, Saturn, Uranus, Neptune

How would a flashing yellow light appear as it fell into a black hole? a. The light would be redshifted and would flash more quickly. b. The light would be blueshifted and would flash more quickly. c. The light would be blueshifted and would flash more slowly. d. The light would be redshifted and would flash more slowly.

d. The light would be redshifted and would flash more slowly.

Which of these stars has the greatest surface temperature? a. a main-sequence M star b. a supergiant A star c. a Cepheid variable star d. a 30 solar-mass main-sequence star

d. a 30 solar-mass main-sequence star

What would you be most likely to find if you returned to the Solar System in 10 billion years? a. a black hole b. a neutron star c. a supernova remnant d. a white dwarf

d. a white dwarf

If you looked at the field of view seen in this Hubble Space telescope with your naked eye, about how big would it appear in the sky? a. about the size of your little finger held at arm's length against the sky b. about the size of the full Moon c. about the size of the Big Dipper d. about the size of an eye of a needle held at arm's length against the sky

d. about the size of an eye of a needle held at arm's length against the sky

Catabolism refers to chemical reactions that: a. maintain a constant level of chemicals. b. grow larger structures. c. transfer genetic information. d. break down structures.

d. break down structures.

What happens to the core of a high-mass star immediately after it runs out of hydrogen? a. it shrinks and cools down b. it goes supernova c. helium fusion begins right away d. it shrinks and heats up

d. it shrinks and heats up