Astronomy 104 Final Review
If a very large(massive) anvil collides with a very small child, which object is subject to a greater force?
They feel the same force
Why are Jupiter and Saturn not perfectly spherical?
They rotate rapidly.
Why did the terrestrial planets lose the majority of the gas in their primary atmospheres?
They were too hot and their escape velocities too low to hold onto them.
In the absence of a greenhouse effect, what would happen to Earth?s oceans?
They would freeze over
In the absence of a greenhouse effect, what would happen to Earth's oceans?
They would freeze over.
When we determine the angular resolution of a single dish telescope using the formulae theta = wavelength/D. The variable D stands for
diameter of the telescopes
A hot, rarified gas will produce what kind of spectrum?
emission line
The balance of energy in the solar interior means that
energy production rate in the core equals the rate of radiation escaping the Sun's surface.
In the absence of the greenhouse effect, the water on the surface of Earth would
freeze
In the absence of the greenhouse effect, the water on the surface of Earth would
freeze.
The net effect of the proton-proton chain is that four hydrogen nuclei are converted to one helium nucleus and _________ are released.
gamma ray photons, positrons, and neutrinos
Which of the following lists different types of electromagnetic radiation in order from the shortest wavelength to the longest wavelength?
gamma rays, ultraviolet, visible, infrared, radio waves
Which scientific theory best accounts for the Solar System's formation?
gravitational contraction of the primordial solar nebula
When sunlight is passed through a spectroscope an absorption spectrum is observed because the Sun
has a hot interior that shines through cooler low density gas
When sunlight is passed through a spectroscope an absorption spectrum is observed because the sun
has a hot interior that shines through cooler low density gas
When sunlight is passed through a spectroscope, an absorption spectrum is observed because the Sun
has a hot interior that shines through cooler low density gas
We can determine how the density changes with radius in the Sun using
helioseismology
The advantage of Hubble Telescope compared to the ground based optical telescopes is
high resolutions(possibility of resolving at tiny angular scales)
The relationship between frequency and wavelength[frequency x wavelength = c] common to all electromagnetic waves tells us that _______.
higher frequencies correspond to shorter wavelengths
Suppose a group of astronomers discovered a new star that is emitting mostly blue light at around 550 nm. What of the following temperature estimation could be possible for this star? (b = 2.898 x 10^6 nmxK
4996 C
A body moves through space with a certain speed. How many forces are needed to make this object move in a circle?
Only one, toward the center of the circle
_________ in our atmosphere is a direct consequence of the emergence of life.
Oxygen
Why is it unlikely to form a gas giant near orbits of a star in a stellar system?
The surface gases of the gas giant will be dragged into the star due to gravity
Why can you see fainter stars with an 8-inch telescope than you can see with your naked eye?
The telescope collects light over a larger area
Why can you see fainter stars with an 8-inch telescope than you can see with your naked eye?
The telescope collects light over a larger area.
Spectral lines are produced by the ________.
transitions or jumps of electrons inside atoms
The greenhouse effect is the
trapping of infrared radiation by the atmosphere.
In Newton's law of gravity, F = -GMm/R^2, the constant G is
universal constant independent of other parameters
The part of the human eye that acts as the detector is the
retina
The Moon undergoes synchronous rotation, and as a consequence the
rotational period of the Moon equals the orbital period of the Moon around Earth
Sunspots appear dark because they have _________ than those of the surrounding gases.
temperatures that are lower
If a collapsing interstellar could formed only a protostar without an accretion disk around it, what would happen?
the forming protostar would be rotating too fast to hold itself together.
What is a primary atmosphere?
the gas captured during the planet's formation
The microlensing method is one of the methods that allow us to identify the exoplanet in observations. The principle behind this method is:
the light of the background star becomes temporary brighter due to the gravity of the exoplanet
One can argue that the heliocentric model of the Solar System was more natural than the geocentric model, based on
the observed retrograde motions of the planets
One can argue that the heliocentric model of the Solar System was more natural than the geocentric model, based on
the observed retrograde motions of the planets. Earth's motion.
What makes carbon dioxide a highly effective greenhouse gas?
it easily absorbs infrared radiation
Earth does not fall onto Sun's surface because
it has large speed
Earth does not fall onto Sun's surface mainly because
it has large speed
How does the light gathering power of a 4m telescope compare to that of a 2m telescope?
it is 8 times as much
Which of the following is not a reason to put a telescope in space?
to get closer to the stars
If Earth's axis were tilted by 5° instead of its actual tilt, how would the seasons be different than they are currently?
Winters would be warmer.
Which of these objects would exhibit an absorption spectrum?
a thin, cool gas cloud that lies in front of a hotter blackbody
How often do leap years occur?
almost every 4 years
The Maunder Minimum was a 60-year period when
almost no sunspots occurred on the Sun
Which of the following choices is produced when white light is shined through a cool gas
an absorption spectrum
If you observe an isolated hot cloud of gas, you will see
an emission spectrum.
Light has aspects of
both a particle and a wave.
The force of gravity that an object has is directly proportional to its
mass.
The giant planets are made primarily of
molecular hydrogen and helium
The primary difference between a moon and a planet is that
moons orbit planets, whereas planets orbit stars
The diameter of the Moon is
more than half the distance across the continental United States.
As energy moves out from the Sun's core towards its surface, it first travels by ______, then ______, and then ______.
radiation; convection; radiation
What is the reason Mercury has so little gas in its atmosphere?
- Its mass is small. -It has a high temperature. - It is close to the Sun.d. Its escape velocity is low.
An accelerating body should/could
-have a changing direction of motion -have a changing velocity -move in curved lines
Whether or not a planet is composed mostly of rock or gas is set by
-its mass -its temperature -its distance from the star when it formed
What is the reason Mercury has so little gas in its atmosphere?
-its mass is small -it has high temperature -it is close to the sun -its escape velocity is too low
The main greenhouse gases in the atmosphere of the terrestrial planets are
. carbon dioxide and water vapor.
During a certain comet's orbit around the Sun, its closest distance to the Sun is 0.6 astronomical Unit(AU), and its farthest distance from the Sun is 35 AU. At what distance will the comet's orbital velocity be the largest?
0.6 Astronomical Unit(AU)
How far away on average is Earth from the Sun?
1 astronomical unit
How far away on average is Earth from the sun?
1 astronomical unit
A 100-kg astronaut throws a 1-kg wrench with a force of 1 N. What is the acceleration of the wrench after the wrench leaves the astronaut's hand?
1 m/s2
The Earth's mass is 80 times larger than the Moon's mass. What is the ratio of the gravitational force that Earth exerts on the Moon to the gravitational force the Moon exerts on the Earth?
1 to 1
Two stars are of equal luminosity. Star A is 10 times as far from you as star B. Star A appears __________ star B.
1/100 as bright as
If a radioactive element has a half-life of 10,000 years, what fraction of it is left in a rock after 40,000 years?
1/16
Two stars are of equal luminosity. Star A is 4 times as far from you as Star B. Star A appears ______ star B.
1/16 as bright as
The nucleus of the typical comet is approximately _____ in size.
10 km
The radius of neptune is about 4 times that of the Earth and its mass is about 17 times of the Earth. Estimate the acceleration due to the gravity of neptune's surface. Given: acceleration due to gravity on Earth's surface g = 9.881 m s^-2
10.4 m s^-2
The Sun's magnetic field reverses direction every
11 years.
Suppose the radius of Jupiter is about 13.2 times that of the Earth and its mass is about 318 times of the Earth. Estimate the acceleration due to the gravity of the planet's surface. Given: the acceleration due to gravity on Earth's surface g = 9.81 m s^2
17.90 m^s-2
Suppose the Earth's mass is 25 times larger than the Moon's mass. What is the ratio of the gravitational force the Earth exerts on the Moon to the gravitational force the Moon exerts on the Earth?
1:1
The transit method is one of the methods that allow us to identify the size of the exoplanet in observations due to the drop of the intensity. Suppose we observe a star using this method and detect two exoplanets with two drops of intensity curve, which is shown in the figure below. For convenience, we overlap the two curves. What is the ratio of the radius between the two planets? Hint: the drop of the intensity curve is related to the area of the planet. (intensity graph shows deltaI and 16deltaI)
1:4
The Moon mass is approximately 7.3 10^22 kilogram. Its radius is 1.7 10^6 meters. The escape velocity from the Moon is approximately
2 km/s
If the temperature of an object were halved, the wavelength where it emits the most amount of radiation will be
2 times longer
If the temperature of an object were halved, the wavelength where it emits the most amount of radiation would be
2 times longer
Suppose we have a protoplanetary system that contains a Sun-Earth system. The system's star is twice as heavy as the Sun, while the mass of the planet is 3 times as heavy as Earth. The separation between the star and the planet in this protoplanetary system is 5 times of that between the Sun and earth. If the instructors weight is 700 N on the Earth, what is his weight on the planet?
2100 N
If a tenth planet were to be discovered with a period of 125 years, what would be the radius of its circular orbit?
25 AU
An object was found in a Solar system with semimajor axis approximately 40 AU. What is its rotational period around the Sun?
250 years
Which of Kepler's laws explains why comets on high eccentricity orbits spend most of their orbital period far from the sun
2nd Law
Given that the Sun's effective temperature is 5700K with its radius of 696,340 km.How many hydrogens convert to helium in a second if all the energy of the sun is coming from the hydrogen to helium fusion process? Hint: For a blackbody object like the Sun, its emitted energy is 4πσR2T4, where T is the effective temperature and σ is the Stefan-Boltzmann constant is given as σ = 5.67x10−8 W⋅m−2⋅K−4.
3.47x1038
Jupiter is approximately _______ times more massive than Earth.
300
The speed of light is approximately
300,000 km/s.
If a new planet is found in the solar system with an orbit distance of 50 AU, what is its period?
350 years
After the Sun, the next nearest star to us is approximately _________ away.
4 light-years
In a simplified nuclear fusion reaction, 4 hydrogens convert to Helium. How much energy released in this process? Note: Mass of four hydrogens (H) nuclei is 1.007 times greater than 1 helium (He) nucleus, the mass of hydrogen is 1.67 x10-27 kg
4.2x10-12 J
One of the nearest stars is Alpha Centauri, light to travel from Alpha Centauri to us?
4.4 years
Suppose a group of astronomers discovered a new star that is emitting mostly blue light at around 400nm. What of the following temperature estimation could be possible for this star? (b = 2.898 x 10^6 nm x K)
6972
The currently broken telescope Arecibo had a diameter of 300 m. Observing at the wavelength of 10 cm, it could resolve objects with the highest resolution of
70 arcsec
An astronaut who weighs 700 N on Earth is located in empty space, very far from any other objects. Approximately what is the mass of the astronaut?
70kg
The average distance between Earth and the Sun is 1.5 * 101 1 m, and light from the Sun takes approximately _________ to reach Earth.
8 minutes
An asteroid is orbiting the Sun at a distance of 4 Astronomical Units. Its period is
8 years
By what factor does the total energy emitted per unit time at all wavelength from a blackbody increase if its temperature increases by a factor of 3
81
Two stars are of equal radius. Star A's effective temperature is 3 times hotter than Star B. What is the ratio of luminosity between star A and star B?
81:1
Human eye diameter is about 8 mm. The Hubble telescope diameter is 2.4 m. The ratio of the light energies from the source collected by the Hubble telescope to the energy collected by the human eye is
90, 000
Why was adaptive optics developed?
to compensate for image distortion by the Earth's atmosphere
What is a protostar?
A large ball of gas not yet hot enough at its core to be a star
Which of the following photons carries the smallest amount of energy?
A microwave photon, whose wavelength is 10^-2 m
Venus's extremely high surface temperature (900F) is accounted for by what process?
A runaway greenhouse effect is maintained by its carbon dioxide atmosphere
Which of the following is false?
A scientific theory is an undisputed fact.
What is the reason Mercury has so little gas in its atmosphere?
ALL OF THE ABOVE -high temperature -mass is small -its escape velocity is low
Which of the observing tasks below may telescopes regularly provide for astronomers?
ALL OF THE OTHER 3 -measuring the intensity -spectroscopy -imaging
Which of the giant planets have rings?
All of them
Is light a particle or a wave?
Both a particle and a wave
Why is it relatively difficult to observe Mercury from Earth?
Because it is a small object and always appears close to the sun in the sky
Why do the giant planets have the largest share of moons in the solar system?
Being the most massive planets in the solar system, they were able to gather more material to form moons than the terrestrial planets
Two rocks (call them S and T) are released at the same time from the same height and start from rest. Rock S has 20 times the mass of rock T. Which rock will fall faster if the only forces involved are each rock's mutual gravitational attraction with Earth?
Both rocks will fall at the same rate.
What does amplitude reveal about light?
Brightness
What is the main reason that Earth's interior is liquid today?
Decay of radioactive elements
Doppler shifts can be measured when
Diffuse, hot gas is moving away from the observer
Which of the following statements is false?
During summer in the northern hemisphere of Mars, the polar ice cap melts and liquid water flows outward from it in rivers.
The Sun rotates once every 25 days relative to the stars. The sun rotates once every 27 days relative to the Earth. Why are these two numbers different?
Earth moves in its orbit during this time
We experience seasons because
Earth's equator is tilted relative to the plane of the solar system
We experience seasons because
Earth's equator is tilted relative to the plane of the solar system.
Leap years occur because
Earth's orbital period is 365.24 days
Prior to colliding with the Earth, most meteorites are thought to originate from the _____.
Fragments of asteroids located between Mars and Jupiter
Which type of electromagnetic radiation must be observed using a space based telescope?
Gamma rays
How did Ptolemy "fix" the geocentric system?
He introduced epicycles.
How does the speed of light traveling through a medium (such as air or glass) compare to the speed of light in a vacuum?
It is always less than the speed of light in a vacuum.
_________ hypothesized that planetary motions could be explained by a force arising from the attraction between the mass of the planet and the Sun that decreased with the square of the distance between them.
Isaac Newton
If the radius of an object's orbit is halved, and angular momentum is conserved, what must happen to the object's speed?
It must be doubled
If the carbon dioxide in Earth's rocks were suddenly released into its atmosphere, what would happen?
It would cause a runaway greenhouse effect
If the carbon dioxide in Earth?s rocks were suddenly released into its atmosphere, what would happen?
It would cause a runaway greenhouse effect
If the carbon dioxide in Earth's rocks were suddenly released into its atmosphere, what would happen?
It would cause a runaway greenhouse effect.
If the Sun instantaneously stopped giving off light, what would happen on the day-side of Earth?
It would get dark 8.3 minutes later.
Suppose by some mysterious process that the nuclear fusion rate in the core of the Sun were to increase. What would happen to the appearance of the Sun?
It would grow larger and hotter, making it more luminous.
If an object is moving in a circular orbit at a constant speed, which of the following is false?
Its acceleration is zero.
Who discovered Neptune?
Johann Galle
________ was the first person to introduce a mathematical heliocentric model of the Solar System from which accurate predictions could be made of planets' positions.
Johannes Kepler
Which planet has the greatest surface gravity?
Jupiter
We all know that some places on Earth have more frequent earthquakes than other places, e.g. Japan, California, Chile. Why don't we usually experience earthquakes in Madison?
Madison is not located at the plate boundaries
The largest volcanic mountains in the Solar System are found on
Mars
We have direct evidence for the current existence of water on the surface of which terrestrial object?
Mars
Most asteroids are located between the orbits of
Mars and Jupiter
Which of the following was not discovered by Galileo using a telescope?
Mars has a polar ice cap similar to Earth.
Mars has a similar size and mass as Earth; so why do we think that the planet lacks a comparable magnetic field?
Mars' metallic core has cool down
Which terrestrial object shows the least evidence of recent volcanic activity?
Mercury
Which statement below does NOT describe one of the advantages of reflecting telescopes over refracting telescopes?
Mirrors reflect only certain colors of light to form an image
_________ is the idea that the simplest explanation for a phenomenon is
Occam's razor
Kepler's third law of planetary motion relates the period P(in years) to the length of the semi major axis, a, in which way?
P^2=a^3
Who of the following was not a proponent of the heliocentric model of the solar system?
Ptolemy
How do the wavelength and frequency of red light compare to the wavelength and frequency of blue light?
Red light has a longer wavelength and lower frequency than blue light.
By measuring the motion of the small moon around Saturn we can find the approximate mass of
Saturn
If you could find a large enough ocean, which one of these planets would float in it?
Saturn
An AU is the distance between
Sun and Earth
What do astronomers mean when they say that the Sun makes energy by hydrogen burning?
The Sun is fusing hydrogen into helium and releasing energy.
In the absence of air friction, a 0.001 kg piece of paper and a 0.1 kg notebook are dropped from the same height and allowed to fall to the ground. How to their accelerations compare?
The accelerations are the same
. In the absence of air friction, a 0.001-kg piece of paper and a 0.1-kg notebook are dropped from the same height and allowed to fall to the ground. How do their accelerations compare?
The accelerations are the same.
Which of the following is true about a comet that is on an elliptical orbit around the Sun?
The comet's speed is greatest when it is nearest the Sun.
Which of the following is not a characteristic of the early Solar System, based on current observations?
The initial composition of the solar nebula varied between its inner and outer regions
Which of the following is not a characteristic of the early Solar System, based on current observations?
The initial composition of the solar nebula varied between its inner and outer regions.
If the distance between 2 astronomical bodies is tripled, what effect does this have on the force of gravity between the two bodies?
The force decreases by a factor of 9
If a collapsing interstellar cloud formed only a protostar without an accretion disk around it, what would happen?
The forming protostar would be rotating too fast to hold itself together.
Which of the following is the most appropriate reason that we do not observe a gas giant orbiting around a terrestrial planet as a satellite?
The gas giant is much heavier than the terrestrial object
The microlensing method is one of the methods that allow us to identify the exoplanet in observations. The principle behind this method is:
The light of the background star becomes temporarily brighter due to the gravity fo the exoplanet
Venus and Earth probably formed with similar amounts of carbon dioxide in their secondary atmospheres. Which of the following is true?
The majority of Earth's carbon is now bound up in rock, whereas Venus's remains in its atmosphere.
Venus and Earth probably formed with similar amounts of carbon dioxide in their secondary atmospheres. Which of the following is true?
The majority of Earth?s carbon is now bound up in rock, whereas Venus?s remains in its atmosphere.
Which of the following is false?
The observed phase of the Moon changes over the course of one night.
Which is not a reason that we suspect Mars once had liquid water on its surface?
The observed presence of water ice in Mars's polar icecaps
the below shows two spectra observed by a group of astronomers. What are these spectra?
Top: Absorption Below: Emission
The greenhouse effect is the
Trapping of infrared radiation by the atmosphere
On which of these planets is the atmospheric greenhouse effect strongest?
Venus
Venus is hot and Mars is cold primarily because:
Venus has a much thicker atmosphere
The terrestrial planets, ranked in order of decreasing atmospheric density are
Venus, Earth, Mars, Mercury
The presence of gases such as carbon dioxide and water vapor in a planet's atmosphere is direct evidence of _________ in a planet's history.
Volcanic activity
What is the difference between visible light and X-rays?
Wavelength; X-rays have a shorter wavelength than visible light.
Which type of electromagnetic radiation must be observed using a space based telescope?
X-Rays
Which of the following photons carries the smallest amount of energy?
a microwave photon, whose wavelength is 10−2 m
The time it takes light to cross Neptune's orbit is closest to which of the following?
a night's sleep
Magnetosphere refers to
a region of magnetic field around Earth.
An atmospheric window is
a region of the electromagnet spectrum that can reach the ground.
Which of these stars would have the biggest redshift?
a star moving at high speed away from you
Which of the following is a bound orbit?
a. elliptical c. circular d. both A and C
A hypothesis is an idea that is
a. falsifiable with current technology. b. potentially falsifiable with future technology. d. both a and b
One reason to prefer a reflecting over a refracting telescope is
a. its lack of chromatic aberration.b. its shorter length for the same aperture size.c. its lack of an aperture limit.d. its lighter weight for larger apertures.e. all of the above
The major advantage CCDs have over other imaging techniques is that
a. they have a higher quantum efficiency. b. they have a linear response to light. c. they yield output in digital format. d. they operate at visible and near-infrared wavelengths. e. all of the above
A theory is
a. tied to known physical laws. b. able to make testable predictions. c. a hypothesis that has withstood many attempts to falsify it. d. all of the above
If the Sun stopped nuclear fusion in its core, how long would it take for its luminosity to change significantly?
about 100,000 years
Earth is located approximately
about halfway out from the center of the Milky Way.
A high mountaintop such as Mauna Kea in Hawaii is a good site for an infrared observatory because it is
above most of the moisture in the Earth's atmosphere
When a cool, rarified gas is placed between a hot, glowing solid and the observer, what kind of spectrum is seen?
absorption line
What is the principal advantage that results from placing astronomical telescopes in orbit around the Earth?
access to the entire electromagnetic spectrum
If we could increase the quantum efficiency of the human eye, it would
allow humans to see better at night or other low-light conditions.
The ______ of a telescope is a measure of its ability to show fine detail and varies inversely with the diameter of the objective lens or mirror
angular resolution
Jupiter's great red spot is a giant
anti-cyclonic (high pressure) vortex
One of the central assumptions in astronomy is that the physical laws of nature
are the same everywhere in the universe.
When you look at the visible surface of a gas giant planet, you are looking at that planet's
atmosphere
The limit of resolution of the biggest ground based telescope is due to
atmospheric distortion of light propagation
Gravity is
b. a fundamental force. c. a mutually attractive force. e. both B and C
Whether or not a planet is composed mostly of rock or gas is set by
b. its temperature c. its distance from the star when it formed. d. a combination of A, B, and C
Consider a star that is significantly more massive and hotter than the sun. For such a star, the habitable zone would
be located outside 1AU
Why is it relatively difficult to observe mercury from Earth?
because it is a very small stellar object that always is too close to the Sun in observations
Our universe is approximately 13.7 _________ years old.
billion
Chromatic aberration results from
blue light being refracted more than red light.
What is a planetesimal?
bodies of ice and rock 100 meters or more in diameter
Which formula denotes how the speed of light is related to its wavelength λ and frequency f?
c = λf
The main greenhouse gases in the atmosphere of the terrestrial planets are
carbon dioxide and water vapor
Kepler's second law says that if a planet is in an elliptical orbit around a star, then the planet moves fastest when the planet is
closest to the star.
The type of spectrum given off by a hot, glowing solid (e.g. a lamp filament) is a(n) _________ spectrum
continuous
The hottest layer of the solar atmosphere is the
corona
Which of the layers of the Sun is located the farthest from the center of the Sun?
corona
The majority of the mass in our universe is made up of
dark matter.
As wavelength increases, the energy of a photon _________ and its frequency _________.
decreases; decreases
Cameras that use adaptive optics provide higher spatial resolution images primarily because
deformable mirrors are used to correct the blurring due to Earth's atmosphere
Cameras that use adaptive optics provide higher spatial resolution images primarily because
deformable mirrors are used to correct the blurring due to Earth's atmosphere.
The early universe was composed mainly of which two elements?
hydrogen and helium
The majority of the Sun's energy comes from
hydrogen fusion.
Kepler's 2nd Law states that a planet moves fastest when it
is closest to the sun
Suppose you read online that "experts have discovered a new planet with a distant from the Sun of 2AU and a period of 3 years". This discovery is not physically plausible because
it violates keplers 3rd law
If the sun instantaneously stopped giving off light, what would happen on the day-side of earth?
it would get dark 8.3 minutes later
If an object is moving in a circular orbit at constant speed, which of the following is false?
its acceleration is zero
Much of the mass in our galaxy appears to be in the form of "dark matter", which can be detected at present because
its gravitational pull affects orbital motion in the galaxy
Much of the mass of our galaxy appears to be in the form of "dark matter", which can be detected at present because
its gravitational pull affects orbital motion in the galaxy
The light from an object gets redshifted due to
its motion away from us
The majority of the energy in our universe is
made up of dark energy that permeates space.
In the radiative zone inside the Sun, photons are transported from the core to the convective zone over a time of
many thousands of years.
How many forces need to be applied to a body in space to keep it moving with a constant velocity?
none
If the Sun is located at one focus of Earth's elliptical orbit, what is at the other focus?
nothing
When two atomic nuclei come together to form a new species of atom, this is called
nuclear fusion.
The net result of the proton-proton chain of nuclear reactions is that four protons are converted into
one helium nucleus, as well as energy, positrons, and neutrinos.
The moon probably formed
out of a collision between Earth and a Mars-sized object.
Which of the following processes did not contribute gas to Earth's secondary atmosphere?
oxidation
Which of the following processes did not contribute gas to Earth?s secondary atmosphere?
oxidation
If photosynthesis were to disappear on Earth,
oxygen would disappear from the atmosphere
If photosynthesis were to disappear on Earth,
oxygen would disappear from the atmosphere.
The time it takes a planet to complete one full orbital revolution is commonly known as its
period
The time it takes a planet to complete one full orbital revolution is commonly known as its
period.
The fact that the speed of light is constant as it travels through a vacuum means that
photons with longer wavelengths have lower frequencies.
Retrograde motion is seen when _____ due to the Earth's motion
planets change the direction in which the move across the night sky
Retrograde motion is seen when ____________ due to Earth's motion
planets change the direction in which they move across the night sky
The Moon undergoes synchronous rotation, and as a consequence the
rotational period of the Moon equals the orbital period of the Moon around Earth
Which of the Kepler laws explains why comets on high eccentricity orbits spend most of their orbital period far from the sun
second law
When we determine the angular resolution of an interferometric array of radio telescopes using the formulae 0=Wavelength/D, the variable D stands for
separation between the telescopes
When we determine the angular resolution of the following object using the formulae theta = wavelength/D, the D stands for
separation between the telescopes
According to the conservation of angular momentum, if an ice-skater who is spinning with her arms out wide slowly pulls them close to her body, this will cause her to . . .
spin faster.
When the northern hemisphere experiences fall, the southern hemisphere experiences
spring.
Newton's first law states that objects in motion
stay in motion unless acted upon by an unbalanced force.
During which season (in the Northern Hemisphere) could you see the Sun rising from the furthest north?
summer
The Local Group is the environment around
the Milky Way that contains a few dozen galaxies.
A partial lunar eclipse occurs when
the Moon passes through part of the Earth's shadow
A partial lunar eclipse occurs when
the Moon passes through part of the Earth's shadow.
Solar and lunar eclipses are rare because
the Moon's orbital plane is tipped by 5.2° relative to Earth's orbital plane.
The ecliptic is defined by the motion of _________ in the sky.
the Sun
A natural greenhouse effect occurs on earth because
the atmosphere allows shorter wave sunlight to enter, but traps longer wave infrared energy re-radiated by the surface
. What is a secondary atmosphere?
the atmosphere that remains after the planet has formed
What is a secondary atmosphere?
the atmosphere that remains after the planet has formed
Tidal forces are caused by
the difference between the strength of the gravitational pull of the Moon and Sun on either side of Earth
Visible light makes up a small portion of the much larger family of radiant energy called ____
the electromagnetic spectrum
Galileo's observations of the sky with his telescope included
the fact that Venus showed phases, similar to those of the Moon
Earth's innermost core is solid, not liquid, because
the pressure is too high for the material to be in a liquid state.
If you go out at exactly 9 P.M. each evening over the course of 1 month, the position of a given star will move westward by tens of degrees. What causes this motion?
the revolution of Earth around the Sun
The mass of a 10kg rock would be _____ if it were located in deep space away from any star
the samee
Nuclei of atoms are held together by
the strong nuclear force.
A black car left in the sunlight becomes hotter than a white car left in the sunlight under the same conditions because
the white car reflects more sunlight than the black car
Astronauts orbiting Earth in the space shuttle experience so-called weightlessness in space because
they are in constant free fall around Earth.
If a very large (massive) anvil collides with a very small child which object is subject to a greater force?
they feel the same force
In the absence of a greenhouse effect, what would happen to Earth's oceans?
they would freeze over
Which of the following is not a reason to put a telescope in space?
to avoid weather on Earth
Astronomers can use ground-based telescopes to observe in the majority of which of the following parts of the electromagnetic spectrum?
visible and radio
Astronomers can use ground-based telescopes to observe the majority of which of the following parts of the electromagnetic spectrum?
visible and radio
A big problem for infrared observations is
water vapor
The color of visible light is determined by its
wavelength.
Which of the following properties of an astronaut changes when he or she is standing on the Moon, relative to when the astronaut is standing on Earth?
weight
The day with the smallest number of daylight hours over the course of the year for a person living in the northern hemisphere is the
winter solstice (Dec. 22)