Extraterrestrial Life Exam 1 Practice

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• If we compress the entire history of the Earth into one year modern humans appear
• An isotope of manganese (Mn) has atomic number 25 and mass number 55. If the atom is neutral, how many protons, electrons, and neutrons does it have?
• Which process dominates heat transfer in the Earth's mantle?
• Chemical analysis of a rock can tell us what the rock is made of.
• According to planetary scientists in the latter half of the 20th century, planets around other stars should be...
• If life is eventually found in the solar system, it will most likely be in the form of
• Crater counts are used to estimate the ages of planetary surfaces. Which of the following is the correct implication?
• Which Greek school of thought naturally led to the possibility of extraterrestrial life?
• Which forecast describes the time frame for detecting spectral signatures of life on planets and moons around other stars?
• A distribution of light consisting of dark lines on a continuous background is referred to as
• Where is life on Mars today most likely to be found, if it exists?
• Planetary scientists use crater counts to estimate the ages of planetary surfaces. Which option correctly represents crater counting's purpose?
• Two asteroids have identical masses. One is twice as far from the Sun as the other. According to Newton's Universal Law of Gravitation, the force on the more distant asteroid is which of the following?
• Which Galileo observation best supports that not all celestial bodies are static?
• If Earth's magnetic field weakened significantly, what would be the most likely consequence?
• Extraterrestrial life is defined to be what?
• Extraterrestrial life elsewhere in the universe could be similar to life on Earth or might be completely different.
• The distance between adjacent peaks of an electromagnetic wave is referred to as its
• Compared to its neutral atom, an ion has the same number of
• Which combination best describes the factors controlling geological activity?
• Which conclusion is suggested by the rapid appearance of life on Earth?
• Even though the heliocentric model has advantages over the Ptolemaic model, it suffered from the assumption that the planets moved in perfect circles about the Sun. What was this assumption?
• Moon formation evidence that Moon material underwent high-temperature processing is best described by which statement?
• Which location is a promising place to search for life beyond Earth?
• Astronomy has shown us that the fundamental laws of physics are the same everywhere in the universe.
• Based on Earth's life surviving across diverse environments, what can be inferred about extraterrestrial life?
• Isotopic dating of solar system materials indicates an age of approximately which value?
• Which gases were the most abundant in the solar nebula?
• When an igneous rock is eroded and then deposited at the bottom of an ocean, it becomes which type of rock?
• Which statement best describes SETI's current activity?
• At its most fundamental level, what is the goal of astrobiology?
• Which sequence of electromagnetic radiations is in order of increasing wavelength?
• A liquid transforms into a gas at the
• What is the strongest evidence for the giant impact origin of the Moon?
• What type of rock is sandstone?
• Which statement best describes the location of the Oort cloud?
• Isotopic analysis of meteorites suggests Earth and the rest of the solar system formed about which time?
• The search for life in the universe is influenced by almost every other branch of science.
• Oort cloud comets are thought to have formed when comets that passed close to one of the Jovian planets were flung outward into the outer reaches of the solar system.
• According to Kepler's 2nd Law, a planet moves fastest in its orbit when it is
• Which method is used to study the Earth's deep interior?
• In the scientific method, a hypothesis is another name for
• Kepler's First Law: Which of the following correctly summarizes the description of planetary orbits?
• According to the material, life on Earth can survive under which range of environmental conditions?
• Why does Earth's surface have very few impact craters despite its size and gravity?
• Which statement best describes asteroids and comets?
• Which rock type is most easily dated using radiometric methods?
• Stellar parallax is the apparent shift in position of nearby stars as the Earth moves around the Sun. Which of the following best explains this shift?
• Which discovery suggests extraterrestrial life may be constructed in a similar fashion to life on Earth?
• The Earth's inner core is primarily composed of which elements?
• Why do the Moon, Mercury, and Mars lack plate tectonics?
• In cosmic structure scales, which sequence correctly orders from smallest to largest?
• Which statement best describes a planetesimal?
• Stellar parallax is observable for stars that are relatively nearby. Which of the following best captures this idea?
• Ooort cloud comets were probably formed when comets that passed close to one of the Jovian planets were flung out into the outer reaches of the solar system.
• Which planets have moons for which subsurface liquids may exist, as mentioned in the material?
• Which statement about greenhouse gases is false?
• A metamorphic rock that is melted and then re-solidified becomes which rock type?
• The main way astronomers determine the physical and chemical properties of an object in the distant universe is through
• Thermal radiation from hot, dense objects produces
• Which structure is smallest in scale among Solar System, Milky Way Galaxy, Local Group, and Local Supercluster?
• The dark plains of the Moon known as maria are best described as which?
• What is the astronomical unit (AU) defined as?
• Jovian planets are best described as which?
• What conditions are required for a planet to have a global magnetic field?
• How do Einstein's and Newton's ideas about gravity differ?
• Scientific models supported by a large, compelling body of evidence are referred to as what?
• What should be done with a scientific model whose predictions are not confirmed experimentally?
• The number of vibrations per second of an electromagnetic wave is referred to as its
• What term describes the sweeping of atmospheric gas particles into space by the Sun?
• Which rock type forms from deposited material that becomes cemented over time?
• Why do we see distant stars as they were in the past rather than as they are now?
• What term is used for planets that orbit stars other than the Sun?
• A scientific model is considered valid if it is consistent with what type of observations?
• Which process is considered an important source of Earth's early atmosphere?
• Which event in 1572 challenged the belief that the heavens were unchanging?
• Johannes Kepler showed that the orbits of the planets were ellipses and not circles. Kepler's First Law states that the orbits of the planets are
• Newton's law predicts how force changes with distance; which description correctly captures this relationship?
• What is the overall implication of these findings for the search for life beyond Earth?
• Evidence for subsurface liquids has been found on the moons of which planets?
• In science, conceptual representations of observed phenomena are called what?
• A scientist tries to determine why a particular car is getting a much lower gas mileage than claimed by the manufacturer by systematically designing experiments to test possible causes for the problem. This is an example of
• The study of life in the universe is best described by which term?
• What did the geocentric model describe?
• The dark maria on the Moon are best described as which of the following?
• Which principle posits that the universe's fundamental parameters are finely tuned to allow life?
• Apollo-era analysis of rocks from the lunar maria suggests they formed roughly during which time span?
• The process by which molecules escape from a liquid into the gas phase is called
• The Local Group and Local Supercluster are examples of
• How many sterilizing impacts have occurred since the heavy bombardment?
• Which unit is used to measure distances within the solar system?
• Pluto and Eris are most likely members of which region?
• Which factors determine the magnitude of geological activity on a terrestrial planet?
• What best describes the greenhouse effect?
• What did Galileo's observations of sunspots and craters contradict?
• Which solar system body is most likely to have evidence for past or present life according to the material?
• Which moon of Jupiter has the strongest evidence for a subsurface ocean of liquid water?
• Which statement best defines a habitable world?
• Without the greenhouse effect, Earth's oceans would be
• According to Occam's Razor, when two models fit observations equally well, which should be chosen?
• Approximately how many stars are there in the Milky Way Galaxy?
• Which model places Earth at the center of the Universe?
• The portrayal of nearly all aliens in movies and on TV as humanoid is probably unrealistic because
• Rocks on another planet that appear to have formed from solidification of molten lava are most likely classified as which rock type?
• Which process creates new oceanic crust at mid-ocean ridges as continents diverge?
• Which region around the solar system is a spherical shell far beyond the planets?
• Two comets are at the same distance from the Sun, but one is three times as massive. According to Newton's law, the gravitational force on the more massive comet is what?
• If we compress the entire history of the Earth into one year, life on Earth appeared
• Which model places the Sun at the center of the solar system with planets orbiting around it?
• A person claims to have been abducted by aliens and subjected to painful medical procedures that left scarring. However, he refuses to allow interested scientists to study his scars. This is an example of
• Which planet's phase observations provided evidence for heliocentric model?
• Which discovery suggests the processes that formed life on Earth could have occurred elsewhere?
• Galileo discovered four moons in orbit about Jupiter; this suggested that
• In a spectrum with dark lines on a continuous background, what term describes that spectrum?
• What form of life are scientists most likely to find first in our solar system?
• According to current astronomical data, approximately how old is the universe?
• In beta decay, what happens to a neutron?
• Which observation is explained by Einstein's General Theory of Relativity but not Newton's Universal Law of Gravitation?
• Which of the following is not one of the three branches listed as most important in life in the universe?
• Which of the following lists the structures in our own part of the universe in order of increasing (smallest to largest) scale?
• Where have the molecular building blocks of life been found?
• Which statement best describes the relationship between distance from the Sun and orbital speed according to Kepler?
• The Doppler effect gives us information on
• The strongest piece of evidence that supports the Big Bang Theory is the
• The nuclei of radioactive isotopes can sometimes give off
• Astronomy has shown us that the Earth is just one planet orbiting an ordinary star in a vast universe.
• Which phenomenon allows us to determine the velocity of an object along our line of sight by shifts in wavelength?
• Galileo discovered that Venus goes through a cycle of phases like the Moon. This suggested that
• The discovery of a supernova by Tycho Brahe in 1572 contradicted the commonly held belief that the universe was
• The end of the last Snowball Earth phase roughly coincides with the start of which period?
• Which planet is considered the most likely to contain evidence of life now or in the past?
• For most of human history it was believed that Earth was at the center of the Universe. This idea is referred to as
• Differentiation is a process by which which description best fits the distribution of materials in the early Earth?
• Scientists are currently studying black holes to try to reconcile the differences between which two theories?
• Kepler's First Law states that planetary orbits are ellipses with the Sun at one focus. Which of the following best restates this law?
• The tiny outer moons of the Jovian planets are most likely which origin?
• The semi-major axis, a, of an elliptical planetary orbit is equal to the
• In the scientific method, what immediately follows a prediction?
• If initially there were X atoms of a radioactive isotope and now there are X/16 atoms, how many half-lives have elapsed?
• Why do fossils typically contain little organic matter?
• Recently astronomers have gained concrete evidence that, in addition to being full of stars, the universe is also full of
• The age of the universe is approximately
• Which rock type is defined by cooling and solidification of molten material?
• Which geologic process is believed to have contributed to long-term climate stability enabling life to evolve?
• Who was the first to suggest that the Earth moves around the Sun?
• If a fossil is found in strata below a layer dated at 8 million years, its age is:
• Where is the Oort cloud located in the solar system?
• Rocks formed by the cooling of molten lava are classified as
• Which gases are recognized as greenhouse gases contributing to Earth's infrared trapping?
• Why are fossils of the earliest life difficult to identify in very old rocks?
• The most abundant materials in the solar nebula were which gases?
• The discovery of rocks dating to about 4.0 billion years ago implies crust formation happened during which time interval?
• The radioactive isotope 226Ra decays to 222Rn. What type of decay is this?
• During the Hadean Eon, life may have existed in which environments?
• For an observation to be considered valid, what must be possible for other scientists to do?
• The carbon dioxide cycle's most important role in Earth's climate regulation is to regulate surface temperature by varying the amount of carbon dioxide in the atmosphere.
• What process describes the creation of new ocean floor as tectonic plates move apart?
• Which ancient observation supported the conclusion that Earth is spherical?
• Which field focuses on life in the universe, including its origin, evolution, distribution, and future?
• The cosmic microwave background radiation is best described as
• In the process of nuclear fusion
• Which component helps shield Earth's atmosphere from solar wind?
• Substances composed of combinations of two or more different atoms are known as
• Kepler's third law states that the farther a planet is from the Sun, the slower it moves in its orbit.
• What describes the formation of the outer Jovian planets?
• Kepler's Third Law relates orbital period to which parameter?
• Which option correctly identifies the primary mechanism for recycling older crustal rocks in the crust?
• In the geocentric model, what is described as surrounding the Earth?
• Chemical analysis of a rock can tell us what the rock is made of?
• The deep interior of the Earth is studied using which method?
• Which statement best describes the role of replication in validating new observations?
• In its elliptical orbit, a planet is closest to the Sun at what point?
• Which type of spectrum is produced by hot, dense objects?
• The circular shape of Earth's shadow on the Moon during a lunar eclipse led ancient Greeks to conclude what about Earth?
• If a planet rotates very slowly, what is the likely effect on its magnetic dynamo?
• Which statement is true about ions relative to neutral atoms?
• Which model centers the Sun in describing planetary motions?
• What is the current research goal regarding the relationship between General Relativity and Quantum Mechanics?
• In Mn-55, how many neutrons are present?
• Which statement correctly describes Kepler's Third Law?
• What is the current primary activity of the SETI program?
• Which three branches of science are most important in our study of life in the universe?
• What holds atoms together?
• The process by which molecules escape from a solid directly into the gas phase is called
• Zircon evidence implies Earth's habitability could have existed as early as how long after formation?
• Which type of spectrum is identified by dark lines on a continuous background?
• The center of the Earth consists of which core structure?
• The end of the Snowball Earth era is associated with the start of which major diversification event?
• Which statement best describes terrestrial planets?
• In the outer regions of the solar nebula, which condensed as ices due to low temperatures, in addition to rock and iron?
• Which statement best describes what astronomers have learned about planets in the universe?
• Which of the following is an organic molecule?
• Where have the molecular building blocks of life been found?
• Terrestrial planets are characterized by which description?
• Which theory explains gravity as the curvature of spacetime?
• Which field of study uses the spectrum of light to infer the presence of chemical elements in distant objects?
• What kind of energy does a speeding bullet possess?
• In science, new observations are considered valid if they can be produced by whom?
• Why does the geological record contain fewer older rocks than younger rocks?
• In the heliocentric (Sun-centered) model, apparent retrograde motion is due to which of the following?
• Which statement correctly describes the force that holds atoms together?
• Apparent retrograde motion occurs when a planet appears to move in which direction relative to the background stars?
• How were the Andes formed?
• Copernicus revived Aristarchus's suggestion of a Sun-centered solar system and described it mathematically. Which figure fits this description?
• Measurement of the spectrum of light reflected from a planet gives us information on its
• What best characterizes the relationship between life science and astronomy in studying life in the universe?
• How did the outer Jovian planets most likely form?
• Using current spacecraft, approximately how long would it take to reach the nearest stars?