Astronomy Test 3
Several gases can absorb and re-radiate infra-red light. The one that is thought to be most affected by human activities is
carbon dioxide
Stars usually come in clusters, all born at about the same time, because
collapsing interstellar clouds usually fragment.
Meteor showers are caused by
comet debris.
The ion tail of a comet
consists of straight streamers.
The strongest evidence that Earth life is all descended from a single self-copying molecule is that all Earth life
contains the same version of molecules that have different mirror-image forms.
Neptune's magnetic North and South poles are
displaced from its rotation axis poles and also from the center of the planet.
Uranus' magnetic North and South poles are
displaced from its rotation axis poles and also from the center of the planet.
An advantage of carbon dioxide as the starting form of carbon for use by living things is that it
dissolves in liquid water.
You may hear about an Earth Impact Warning at a certain level on the Torino Scale. That scale ranges from zero to
10
As of July, 2018, The number of confirmed exoplanets found by the transit photometry method is closest to
2500.
Compared to the frequency of photons absorbed during a transition from a -5ev state to a -4ev state, transitions from the -5ev state to a -1ev state would correspond to absorbing photons whose frequency is
4 times as high.
Which of these moons has landmarks that are not rotating with the rest of the moon, indicating a subsurface ocean?
Titan.
The number of near-Earth asteroids is large because they
are kicked out of the asteroid belt by jupiters gravity
Comets that originate in the Outer Oort Cloud have orbits that are
at all angles to the plane of the solar system.
The Oort cloud of our Sun reaches
at least a quarter of the way to the nearest star.
As of 2018, the search for near-Earth asteroids that could threaten global effects has most likely
found more than 90% of them.
The reason the temperature rises as you go higher in the thermosphere is that the Sun's
high energy particles heat the ionosphere.
When ice melts, the resulting liquid water occupies
less volume than the ice did.
The surface of Jupiter is marked by
light and dark bands circulating in opposite directions.
The original source of energy for life forms that live near a black smoker is
often chemicals generated by the heat of the Earth's interior.
Asteroids a few meters in diameter hit the Earth's atmosphere
once every few years and cause air bursts similar to small nuclear weapons.
Oxygen is
one of the four most common elements in the universe.
The habitable zone of a planetary system is defined to be the region where
planetary surfaces permit the existence of liquid water.
The term 'greenhouse effect' refers to
the absorption of infrared light by gases in the atmosphere.
In SETI programs, the "water hole" refers to
the range of signal frequencies between emissions caused by hydrogen and hydroxyl molecules.
The spacecraft Galileo
went into orbit around the planet Jupiter and dropped a probe into its atmosphere.
If we wish to find life with a carbon-return process similar to the one here on Earth, we should look for planets
with thin, unstable surfaces.
In a region of the atmosphere in which the temperature falls with increasing altitude
you expect rapid changes.
The largest moon of pluto (Charon) has
1/2 the diameter of Pluto
The number of moons of Uranus that are larger than Earth's Moon is
0
The number of objects that have been observed to be orbiting in the Outer Oort Cloud is approximately
0
In the Earth's atmosphere, the percentage that is Carbon Dioxide is roughly
0.04%.
As of 2018, how many space probes had flown past Uranus closely enough to take detailed pictures?
1
As of 2018, how many space probes have flown past Neptune closely enough to take detailed pictures?
1
Saturn rotates on its axis once in about
10 hours.
An asteroid whose impact generates a planet-wide catastrophe, changing the climate everywhere, probably has a diameter of about
1000 to 10,000 meters.
The Earth's distance from the Sun is defined to be 1 astronomical unit. Neptune is about 30 astronomical units from the Sun. An object in the Inner Oort Cloud might be at a distance from the Sun of
15,000 au
Compared to the frequency of photons absorbed during a transition from a -5ev state to a -4ev state, transitions from the -5ev state to a -2ev state would correspond to absorbing photons whose frequency is
2 times as high.
As of July, 2018, The number of confirmed exoplanets found by the transit photometry method is closest to
2500
The inclination angle of a planet's rotation axis is defined so that a planet that is rotating in the usual direction about an axis that is perpendicular to the plane of the solar system would have an inclination of 0°, while a planet that is rotating in the opposite (retrograde) direction about an axis that is perpendicular to the plane of the solar system would have an inclination angle of 180°. The inclination angle of the planet Neptune is closest to
30 degrees
The asteroid 2007 VK184 has one chance in 2940 of hitting the Earth between the years 2048 and 2057. The asteroid is 130 meters in diameter or about half the size of Apophis. Assuming that an impact could cause the death of 1,000,000 people the average death rate for this type of event is closest to
350 people per event
The inclination angle of a planet's rotation axis is defined so that a planet that is rotating in the usual direction about an axis that is perpendicular to the plane of the solar system would have an inclination of 0°, while a planet that is rotating in the opposite (retrograde) direction about an axis that is perpendicular to the plane of the solar system would have an inclination angle of 180°. The inclination angle of the planet Uranus is closest to
98 degrees
Which of these is a statement of the Fermi Paradox?
Any long-lasting technological civilization should be obvious and might even be visiting us, so where are they?
If we should find micro-organisms on Mars that reproduce using a DNA/RNA scheme and set of amino acids that are mirror images of those used in all Earth life-forms, that would support the
Abiogenesis Model.
Titans atomosphere has....?
An atmosphere whose temperature and pressure permit liquid methane
Underneath the Atlantic Ocean is an undersea mountain range called the MidAtlantic Ridge. That ridge is caused by
An upward current in the Earth's Mantel.
The Kuiper Belt is mostly located
Beyond the orbit of Neptune
Which of the following substances is the smallest fraction of our atmosphere?
Carbon Dioxide
Which of the following systems do most living things on Earth now use to reproduce themselves?
Each DNA molecule splits in half and each half acts as a pattern to complete its other half.
What we refer to as a "saturn ring-plane crossing" corresponds to what season on Saturn?
Fall or spring equinox
As of 2018, the search for near-Earth asteroids that could threaten global effects has most likely
Found more than 90% of them
The first spacecraft to go into orbit around Jupiter was
Galileo.
Gerard Kuiper predicted that the region we now call the "Kuiper Belt" should be empty.
He was incorrect because he assumed a mass for Pluto that is now known to be too large.
It has been argued that hydrogen-powered automobiles can solve our energy problems because we can get all of the hydrogen that we need from sea water. Which of the following comments about the energy needed to separate the hydrogen and oxygen in water is correct?
It is the same as the energy released when the hydrogen is burned, so we get no net gain of energy.
The New Horizons space probe made close approaches to
Jupiter and Pluto.
The most likely candidate for a second star in our Solar system was
Jupiter.
The temperature on Jupiter is
Much colder than anywhere on Earth.
Which of the following statements qualifies as a falsifiable working hypothesis of the sort that Karl Popper would favor?
Life arose on Earth and exists only there.
You hear a loud noise outside and go outside to find a smoking rock embedded in your driveway underneath your wrecked car. The object is probably a
Meteorites
Which of the following objects has a magnetic field whose North and South poles are displaced from its rotation axis poles and also from the center of the planet?
Neptune
As seen from far above the Earth's North Pole, the Earth orbits the Sun counter clockwise and
No planet orbits the Sun clockwise.
As seen from far above the Earth's South Pole, the Earth orbits the Sun clockwise and
No planet orbits the Sun counterclockwise.
On Earth, a stable long-term carbon cycle could not exist without
Plate tectonics recycling the sea floor into the Earth's interior
The search for extrasolar planets has started to find "super-Earths," planets several times as large as Earth but with about the same density. From what we understand so far about plate tectonics on Earth, how likely is it that these super-Earths would have active surfaces like ours?
Possible if other conditions are also present.
You are having central air conditioning installed in your two-story house and you have a choice between putting the vents on the second floor and putting them on the first floor. Of course, it would be best to put them in both places but you can't do that. Which of the options that you have is best?
Put the vents on the second floor so that the cooled air will descend to the first floor.
A single sugar phosphate chain with nitrogenous bases attached along it describes a molecule of
RNA.
Which of the following features in the light reflected from a planet would indicate the presence of Earth-type plants (rather than just colored rocks) on its surface?
Red light is not reflected, but infra-red light is strongly reflected.
Which of the following planets has a hexagon-shaped pattern of clouds near its North Pole?
Saturn
The Viking Landers carried out several experiments on Martian surface soil. The final conclusion from those experiments (as interpreted at the time) was:
The surface of Mars is extremely hostile to all forms of organic matter
Upon close examination by space probes, the rings of Saturn are found to consist of?
Thousands of circular rings
Which of the following planets or moons has an atmosphere with about 1.6 times the surface pressure of Earth's?
Titan
Which of these moons could have two levels of oceans, with oceans of liquid hydrocarbons on the surface and oceans of liquid water beneath the surface?
Titan.
Which of the following planets is about 4 times the size of the Earth?
Uranus
Which of the following spacecraft was the second to fly past Saturn and the first to target the moon Titan?
Voyager 1
Which of the following spacecraft is the only one to have flown past Uranus?
Voyager 2
The Cassini-Huygens spacecraft did what...?
Went into orbit around the planet Saturn
Based on our observations of planetary systems that are forming now, which of these situations is LEAST likely to occur on a planet in a distant binary star system?
You see two suns, both of them looking similar in size to our own Sun, in widely separated parts of the sky
The Earth's core consists of
a central core of solid iron and an outer core of liquid iron.
Underneath a place where the sea floor is disappearing into a deep ocean trench, one expects there to be
a descending convection current in the Earth's mantle
Jupiter has
a few rings made of dark rocks.
Civilizations capable of sending out broadcast messages that we could possibly detect across interstellar distances would have to be technologically advanced and would probably be much more advanced than we are. That makes it difficult to decide what sort of signals they would send. The SETI program has decided to listen for microwave signals rather than more exotic types of signals (such as laser light, gamma rays, neutrinos, gravitational waves, etc.). The main reason for this choice is that
a microwave signal can send the largest amount of information for a given amount of energy used to generate the signal.
A rising convection current in the Earth's mantle is expected to cause
a mid-ocean ridge where tectonic plates are spreading apart.
Light that has been spread out to show the frequencies or colors that are present is called
a spectrum.
Saturn's magnetic North and South poles are
almost exactly aligned with its rotation axis.
Here is the Drake Equation. In this equation, n_{e} stands for the
average number of habitable planets in a planetary system.
The tail of a comet always points
away from the Sun.
The tail of a comet always points
away from the sun
Jupiter failed to become a star because
because it has a starlike composition but lacks the nuclear
A "rogue planet" or planetary mass objects that is not in orbit around any particular star
could be detected if its gravity magnifies the light from a star. that it happens to pass in front of.
Current computer models of planet formation suggest that the Alpha Centauri system
could have planets within the habitable zones of both Alpha Centauri A and Alpha Centauri B.
According to our current (very tentative) estimates, a spaceship traveling from our Sun to one of the nearest stars such as Alpha Centauri A probably
could make the trip in many short hops between rogue planets along the way.
The orbit of Pluto
crosses the orbit of Neptune.
Early (before 1970) theoretical estimates of the number of near-Earth asteroids were very low because the astronomers of that time
did not realize that Jupiter's gravity was deflecting asteroids from the Belt.
Europe and North America are
each on different plates and moving away from each other
The semiliquid rock that is found inside the Earth
flows like a liquid under gradual pressure but is stiff like a solid under sudden pressure.
The absorption and re-radiation of infrared light by gases such as carbon dioxide is the key process in the
greenhouse Effect.
The moon Miranda is peculiar because it
has a surface feature that looks like a giant check mark.
If we detect that a star is sometimes moving toward us and sometimes moving away and also find that this pattern repeats at regular intervals, we know for sure that the star
has at least one object of unknown type orbiting around it.
If we detect that the intensity of the light from a star is mostly constant but drops slightly to a new constant value for a while and then returns to its normal level and repeats this behavior at regular intervals, we can reasonably suspect that
he star has a planet in orbit around it.
Which of the following types of radiation has the second lowest frequency on this list?
heat radiation.
The second most common element in the universe is
helium.
The Kuiper Belt is thought to have originated when
icy objects condensed out just beyond Neptune
Protostars are very bright because of their large surface areas. Most of this energy comes out as
infra-red light with wavelengths too long to see with an ordinary telescope.
Which of the following types of radiation has the second lowest frequency on this list?
infrared light
Seismic waves are used to determine the Earth's
interior structure.
If the frequency of electromagnetic radiation goes from 2×10¹⁴Hz to 6×10¹⁴Hz, the energy of each individual photon in the radiation
is multiplied by 3
If the frequency of electromagnetic radiation goes from 3×10¹⁴Hz to 9×10¹⁴Hz, the energy of each individual photon in the radiation
is multiplied by 3.
The photosphere of a protostar
is where light is last scattered
The photosphere of a protostar
is where light is last scattered.
The main reason to suspect that Titan has a subsurface ocean of water is
landmarks that are not rotating with the rest of the moon.
If we wish to find life with a carbon-return process similar to the one here on Earth, we should look for planets
larger than Mars.
As compared to higher frequency electromagnetic radiation, lower frequency electromagnetic radiation will usually cause
less damage.
Comparing asteroids hitting the Earth at the same speed, the energy released by an asteroid impact is proportional to (Be careful here!) the
mass of the asteroid.
When the fireball of its entry into the atmosphere was spotted from a KLM airliner, asteroid 2008 TC₃ had officially become a
meteor.
Comets that originate in the Inner Oort Cloud would be expected to have orbits that are
mostly close to the plane of the solar system
In the Earth's atmosphere, the amount of carbon dioxide is
much less than the typical amount of water.
According to the definition of "habitable zone" that we are using, Earth is
near the inner edge of the habitable zone of our Solar System.
One of the experiments carried out by the Viking Landers was to use a mass spectrometer to analyze the gas given off from a heated soil sample. The results of that experiment (as interpreted at the time) established that Martian soil contains
no carbon compounds at all.
The Viking Landers carried out several experiments on Martian surface soil. One of those experiments, the Pyrolytic Release Experiment gave a positive result for the presence of life forms. That result was interpreted to mean
nothing because a sterilized control sample gave the same result.
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 (2018) indicate that
possibilities (2) and (3) actually happen.
When a seismometer detects an earthquake, the first signal to arrive is usually the
pressure wave
When a seismometer detects an earthquake, the first signal to arrive is usually the
pressure wave.
If an asteroid that is 50 meters in diameter strikes the Earth, the result is likely to be
similar to a nuclear explosion
The Kepler Spacecraft was designed to measure
small changes in starlight from nearby stars.
A large asteroid impact causes the extinction of whole species mainly by the effects of the
smoke and dust. it blocks the sunlight
Icy objects condensed from the outskirts of the Solar Nebula to form
the Kuiper belt.
In a region of the atmosphere in which the temperature rises with increasing altitude
stratosphere
The layer of the atmosphere that tends to retain dust and smoke for long periods of time is the
stratosphere.
The molecules of both liquid water and ice are held together by
the attraction between the hydrogen atoms on one water molecule and the oppositely charged oxygen atom on another.
A hydrogen bond is the result of
the electrical attraction between a hydrogen atom on one molecule and an oppositely charged part of another molecule.
Mars retains a carbon dioxide atmosphere because
the pressure is very close to the triple point of water.
The main reason that the SETI@home system needs to use the computing power of 5.2 million participating home computers is that
they are collecting and analyzing signals from millions of different radio channels.
The magnetic field of Jupiter is
tilted relative to the planet's rotation axis but not offset from its center.
In which of these layers of the atmosphere is it generally colder at higher altitudes?
troposphere.
The Alpha Centauri star system consists of
two stars in close orbit around each other and a third star orbiting farther out.
The Surface of pluto can best be described as?
varied with ice mountains and almost no craters at all.
A world with both liquid water on its surface and carbon dioxide in its atmosphere is unstable because
water dissolves carbon dioxide and it takes it out of the atmosphere
A world with both liquid water on its surface and carbon dioxide in its atmosphere is unstable because
water dissolves carbon dioxide and takes it out of the atmosphere.
