Mastering astronomy Assignment 2

__Astronomy has shown us that the Earth__

* is the only planet in the universe with advanced life
* occupies a special location in the universe so that life elsewhere is unlikely
* is just one planet orbiting an ordinary star in a vast universe
* is the only planet in the universe with any kind of life

is just one planet orbiting an ordinary star in a vast universe

__For most of human history it was believed that the Earth was at the center of the universe. This idea is referred to as__

* stellocentric
* egocentric
* geocentric
* heliocentric

geocentric

__A habitable world is defined to be one that__

* has an atmosphere
* has conditions suitable for life
* is identical to the Earth
* is in orbit about a solar-type star

has conditions suitable for life

__Extraterrestrial life elsewhere in the universe__

* will be completely different than life on Earth
* will be unrecognizable
* will be identical to life on Earth
* could be similar to life on Earth or might be completely different

could be similar to life on Earth or might be completely different

__Astronomy has shown us that the fundamental laws of physics are__

* completely random and unpredictable
* different on other planets in our solar system
* the same everywhere in the universe
* the same in our solar system but different beyond the solar system

the same everywhere in the universe

__The fact that the life on Earth seems to have appeared quite rapidly suggests that life__

* can arise on most habitable worlds
* on any kind of planet is inevitable
* can only appear soon after a planet forms
* is only possible on Earth-like planets

can arise on most habitable worlds

__The discovery of any kind of life beyond the Earth would__:

* only be on interest to biologists
* be of interest to all scientists, but of little interest to the wider public
* be of no interest to anyone at all
* cause a profound change in perspective of the whole of humanity

cause a profound change in perspective of the whole of humanity

__The molecular building blocks of life have been found__

* on the Earth and in meteorites
* only on the Earth
* on the Earth, in interstellar clouds, and in meteorites
* on the Earth and on Mars

on the Earth, in interstellar clouds, and in meteorites

__Which three branches of science are most important in our study of life in the universe?__

* physics, mathematics, and astronomy
* astronomy, planetary science, and biology
* planetary science, biology, and mathematics
* biology, mathematics, and physics

astronomy, planetary science, and biology

__The discovery of extrasolar planets indicates that planets around other stars are__

* common
* nonexistent
* all Earth-like
* relatively rare

common

__Biologists have found that life on Earth can__

* survive over only a very narrow range of environmental conditions
* only survive on the surface of the Earth
* survive only in the presence of sunlight
* survive over a wide range of environmental conditions

survive over a wide range of environmental conditions

__Humanity has been thinking about the possibility of extraterrestrial life__

* throughout human history since the time of the ancient Greeks
* since reports of canals on Mars were first made in the 1870's
* since the first reports of unidentified flying objects in the 1940's

* throughout human history since the time of the ancient Greeks

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__Extraterrestrial life is defined to be__

* advanced life forms that have visited the Earth
* life found beyond the Earth which is based on the same biology and chemistry as life on Earth
* advanced life found on Earth-like planets around other stars
* any kind of life found beyond the Earth

any kind of life found beyond the Earth

__The portrayal of nearly all aliens in movies and on TV as being humanoid is__

* realistic because the human form has several unique qualities that make it a good choice for any advanced civilization
* probably unrealistic because the human form is most likely a result of the particular conditions and events that occurred on the Earth
* based on the fact that it would be impossible for us to understand anything that wasn't very similar to a human
* based on the fact that the human form is the only possible form for an advanced civilization

probably unrealistic because the human form is most likely a result of the particular conditions and events that occurred on the Earth

__If life exists on Mars today it will most likely be found__

* everywhere—on the surface, beneath the surface, and in its atmosphere
* beneath the surface
* on the surface
* in its atmosphere

beneath the surface