Cold-dark-matter models predict:
A) large-scale filaments containing both normal matter and dark matter.
B) no structure on a smaller scale than superclusters.
C) the universe is less than 10 billion years old.
D) dense regions of the early universe that led to galaxies formed after decoupling.
E) that dark matter is the largest component of the universe's density.
Question 2The magnetic field of Mars was first detected by the Mars Global Surveyor.
Indicate whether the statement is true or false
Question 3In space, positive ions are the result of:
A) protons escaping from the nuclei of atoms at tremendous temperatures.
B) electrons being stripped off the outer electron shell for hot atoms.
C) positrons being added to the atomic nucleus at great energies.
D) positrons being added to the electron clouds, destroying the electrons.
E) electrons being added to the cloud, giving them a surplus over protons.
Question 4Density waves may explain:
A) the lack of blue stars in the halo.
B) the random orbits of halo stars.
C) the density of red stars in the bulge.
D) the spiral arm structure of the Galaxy.
E) the large number of open clusters in the halo.
Question 5What happens to the rotation of a molecular cloud as it collapses to form a star?
A) The rotation rate remains the same and results in stellar rotation.
B) The rotation dissipates and any residual is left in small overall rotation of the star.
C) The rotation rate increases and results in fast rotation of the star.
D) The rotation rate increases and results in a flattened disk of material around a protostar.
E) The rotation increases the speed of collapse and produces more massive stars.
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