Astronomy Ch 5 HSU – Flashcards
Unlock all answers in this set
Unlock answersquestion
At what point in time do we say that the protosun became the Sun?
answer
When thermonuclear fusion reactions began at its center.
question
Compared to the orbital distance of Earth from the Sun, the equivalent orbital distances for the outer planets are
answer
greater than 5 times.
question
Fusion is the process by which
answer
elements are transformed into heavier elements by nuclear reactions.
question
In order of increasing density, the large, outer planets would be listed as
answer
Saturn, Uranus, Jupiter, Neptune.
question
In our solar system, which of the following planets is NOT a member of the terrestrial group?
answer
Jupiter
question
In our solar system, which of the following planets is a member of the terrestrial group?
answer
Mars
question
Most of the planets orbit the Sun on or close to
answer
the ecliptic plane.
question
The asteroid belt exists between the orbits of which planets?
answer
Mars and Jupiter
question
The average density of the large, outer planets is
answer
close to the density of water.
question
The birthplace of the Sun and planets (and of other stars and maybe their planets) is thought to have been
answer
in cool gas and dust clouds.
question
The correct sequence of planets in our solar system, from the Sun outward, is
answer
Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune.
question
The dwarf planet whose orbit has the greatest inclination to the plane of the ecliptic is
answer
Pluto.
question
The largest of the terrestrial planets is
answer
Earth.
question
The manner in which the terrestrial planets formed was
answer
accretion of solid planetesimals containing mostly rocky material.
question
The most abundant material in the universe is
answer
hydrogen.
question
The most likely mechanism for the solar system is that
answer
the Sun and planets slowly condensed to their present form from a gas and dust cloud.
question
The most probable theory for the formation of the solar system is
answer
condensation of a nebula of cold gas and dust into the Sun and planets.
question
The overall shape of the orbits of most of the planets in the solar system is
answer
slightly elliptical, but nearly circular.
question
The planet with the greatest mean density is
answer
Earth.
question
The planets whose orbits are most noticeably elliptical are
answer
Mercury and Pluto.
question
The smallest of the planets is
answer
Mercury.
question
The smallest terrestrial planet is
answer
Mercury.
question
The steps in which the large, outer planets formed were
answer
accretion of planetesimals to form a core, followed by gravitational capture of hydrogen and helium gas.
question
What name is given to the concentration of mass that formed at the center of the solar nebula, and eventually became the Sun?
answer
The protosun.
question
Where in the universe are heavy elements, with masses greater than that of helium, being produced at this time?
answer
In the central cores of stars.
