Exam 1 Flashcards
Which is the correct sequence of planets, based on increasing average radius of their orbits?
Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto
The inner planets ______________________.
Have the same composition as the outer planets
Same size as the outer planets
Have an orbiting system of rings
Have several moons
Which statement is true for the outer planets of our solar system?
They are largely made of hydrogen and helium.
Water ice is __________________________.
most abundant on the moons
What sets the composition of the moons of the outer planets apart from the inner planets?
The moons of the outer planets generally have lower densities.
Which objects have orbits that take them the farthest from the Sun in our solar system?
Comets
Some comets have orbital periods of hundreds of thousands of years. The group of comets that occupies the outermost limits of the solar system is called the Oort cloud.
Which of the following objects is most like Earth in size and composition?
A. Mercury
B. Ida
C. Mars
D. Venus
Venus
What is a major difference between planets and stars?
A. Planets are much smaller in diameter than the stars around which they revolve.
B. Planets do not generate energy through nuclear fusion.
Planets have rings and systems of orbiting moons and some planets (the outer planets) lack solid surfaces.
What are the major differences between a moon and a planet?
A.Planets revolve around the Sun.
B. Moons revolve around a Sun-orbiting planet.
A few moons are actually bigger than Pluto and Mercury. By definition, moons (natural satellites) don’t orbit the Sun but instead revolve around another planetary body. Some asteroids even have moons.
Which of the following are the characteristics of the asteroid belt?
B. The asteroids mark the transition from the rocky terrestrial planets to the outer planets.
C. Some asteroids appear to be rocky; some seem covered with lava; others seem to be metallic; and yet others may have water ice.
D. Many meteorites that fall on Earth come from the asteroid belt.
According to our best modern day evidence, how long ago was the Big Bang?
About 14 billion years ago.
the most basic subatomic particles include which of the following? (Select all that apply.)
A. Protons B. Neutrons C. Isotopes D. Ions E. Electrons
A, B & E
How are elements heavier than iron produced?
During a supernova explosion
What is the principal method of light element (up to iron, atomic number 26) production?
nuclear fusion
The T-Tauri phase of a star’s history ______________________.
s typified by extreme fluctuations in energy and a strong magnetic field
Many supernovas are the result of _____________________.
collapse of a star with multiple burning shells
How will the Sun’s life probably end?
With the formation of a planetary nebula.
Which of the following are correct about red giant stars? (Select all that apply.)
A. Krypton, home to Superman, was a red giant.
B. They form as a star expands and the surface cools.
C. They are among the stars with the hottest surfaces.
D. They evolve from medium-sized stars.
They evolve from large stars.
Heavy elements like uranium and thorium form in their interiors.
B&D
Put the following stages in the evolution of a medium-sized star in the correct time order, placing the first stage on the top and the last stage on the bottom. Don’t use those that don’t apply to a medium-sized star.
Gas and Dust, Protostar, Main sequence star, red giant, planetary nebula
Which kind of stars have the longest lifetimes (~10 billion years)?
Medium-sized stars like our Sun.
A giant molecular cloud is best described by which statement?
It is a cool mass of gas and dust that can be light years across.
Which of the following is correct about the nebulas we see in the sky today? (Select all that apply.)
A. They formed during the “Big Bang.”
B. They are concentrations of interstellar gas and dust.
C. Many are the birth grounds of stars.
D. Some form when stars explode.
B, C, & D
A “star” that shines, but not as a result of nuclear reactions, is called a __________.
protostar
Condensation in the solar nebula and accretion of planets is thought to have occurred about how many years ago?
Ages from meteorites suggest condensation occurred 4.5 billion years ago.