Astronomy 1002, section 0459
Quiz 3: These are example questions (somewhat harder than the average exam question) on material covered since midterm 2, including lectures after HW7, to help you prepare for the Final Exam. Quiz 3 will not be collected and graded.

 
1. Star cluster A is 10 billion years old and star cluster B is one million years old. At birth they had the same mass. Which statement is correct?

a) A contains more massive stars than B

b) B contains more white dwarf stars than A

c) A contains more red giant stars than B

d) A is more luminous than B

e) A is bluer than B

 

2. Elliptical and Spiral galaxies. Which is the correct statement?

a) Elliptical galaxies are bluer than spiral galaxies

b) Spiral galaxies form from mergers of ellipticals

c) Ellipticals tend to be found in centers of clusters of galaxies

d) The Sun is part of an elliptical galaxy

e) Elliptical galaxies have more active star formation than spirals

 

3. A Universe with a density _____ the critical density will ______ .

a) higher than; expand forever

b) lower than; end in a big crunch

c) the same as; end in a big crunch

d) lower than; expand forever

e) higher than; have an infinite volume

 

4. A star 30 times the mass of the Sun ______

a) can end its life as a white dwarf

b) is usually found in elliptical galaxies

c) may explode as a supernova to leave a neutron star

d) supports itself by fusing iron into uranium

e) lives longer than our Sun

 

5. Type I supernovae _______

a) are the fate of all low mass stars

b) repeat every 50 to 100 years

c) are the collapse of massive stars to black holes or neutron stars

d) are explosions which destroy white dwarfs

e) are the collision between two red giant stars

 

6. Hubble's constant is 70 km/s per Mpc. A distant galaxy is observed to be receding from us at 1400 km/s. How far away is it?

a) 10 Mpc

b) 20 Mpc

c) 70 Mpc

d) 100 Mpc

e) 200 Mpc

 

7. A spectral line in a particular galaxy is observed to be at a wavelength of 5500 Angstroms instead of the normal 5000 Angstroms. How fast is the galaxy moving? (the speed of light is 300,000 km/s)

a) 3,000 km/s towards us

b) 3,000 km/s away from us

c) 30,000 km/s towards us

d) 30,000 km/s away from us

 

8. Astronomers believe in the existence of Dark Matter because

a) the orbital velocity of stars and gas in the Milky Way are fairly constant with Galactic radius

b) galaxies in clusters have quite high velocities

c) very hot gas is seen in clusters of galaxies

d) galaxy clusters act as strong gravitational lenses

e) all of the other answers

 

9. Which of the following is not a factor in the Drake equation for estimating the number of technological civilizations in the Galaxy?

a) the star formation rate of the Galaxy

b) the fraction of stars with planets

c) the fraction of planets suitable for life

d) the number of planetary nebulae in the Galaxy

e) the average lifetime of technological civilizations

 

10. The Big Bang theory explains

a) the ratio of numbers of spiral to elliptical galaxies

b) the presence of dark matter in galaxies

c) the abundance of helium in interstellar gas

d) the acceleration of the Universe

e) the emergence of life in the Universe

 

11. What important molecules for life were found in the first Miller-Urey experiment?

a) Simple DNA.

b) Fatty acids.

c) Proteins.

d) Simple RNA.

e) Amino acids.

 

12. Which of the following factors from the Drake equation has a value which is currently well constrained?

a) Rate of star formation.

b) Average lifetime of a civilization.

c) Fraction of stars having a planetary system.

d) Fraction of life-bearing planets on which intelligence evolves.

e) Fraction of intelligent-life planets that develop technology.

 

13. Assuming that conditions ripe for life and intelligence abound in the Galaxy, what factor limits the number of Galactic civilizations?

a) The average survival time for civilizations.

b) The distance between civilizations.

c) The distance of civilization from the center of the Galaxy.

d) The development of technology.