1. By the first century C.E. stars had been classified, according to their brightness, into
a. two classes.     b. four classes.     c. five classes.     d. six classes.     e. ten classes.

2. A star that appears brighter to an observer on Earth has a lower
a. absolute magnitude.     b. color temperature.     c. declination.     d. apparent magnitude.     e. altitude.

3. A star that is 100 times fainter than another star at the same distance will be
a. 1 magnitude dimmer.     b. 2.5 magnitudes dimmer.     c. 3 magnitudes dimmer.     d. 5 magnitudes dimmer.     e. 10 magnitudes dimmer.

4. A star that is 2 magnitudes dimmer when compared with another star at the same distance is about
a. 2 times less luminous.     b. 3 times less luminous.     c. 6 times less luminous.     d. 10 times less luminous.     e. 15 times less luminous.

5. A star that is about 6 times more luminous than a +5 magnitude star at the same distance will have a magnitude of about
a. -2.     b. -1.     c. +1.     d. +3.     e. +7.

6. The study of the positions of stars and their motions across the sky is
a. astrometry.     b. color indexing.     c. spectroscopic parallax.     d. speckle interferometry.     e. trigonometric parallax.

7. The angle at which a star appears to move when observed from the ends of a baseline of 1 A.U. is the star's
a. proper motion.     b. radial velocity.     c. space velocity.     d. parallax.     e. speckle.

8. The magnitude a star would have if it were at a standard distance of 10 parsecs is its
a. absolute magnitude.     b. apparent magnitude.     c. standard magnitude.     d. luminosity.     e. relative luminosity.

9. A star that is 40 parsecs from the Sun would, if moved to a distance of 10 parsecs, be
a. 4 times brighter.     b. 4 times dimmer.     c. 16 times brighter.     d. 16 times dimmer.     e. 4 magnitudes brighter.

10. A graph of temperature versus magnitude for stars is sometimes known as a(n)
a. astrometric chart.     b. color-temperature diagram.     c. Hertzsprung-Russell diagram.     d. periodic table.     e. star chart.

11. A temperature-luminosity diagram of stars usually includes a diagonal band called the
a. H-R line.     b. main line.     c. main sequence.     d. color index.     e. star diagonal.

12. Waves emitted at 4000 Angstroms by a star moving away at 1/10 the speed of light will be shifted by
a. 4 Angstroms.     b. 10 Angstroms.     c. 40 Angstroms.     d. 100 Angstroms.     e. 400 Angstroms.

13. The angular rate of the change of position of a star in the sky is its
a. relative velocity.     b. proper motion.     c. radial velocity.     d. space velocity.     e. transverse velocity.

14. The speed of an object in the direction toward or away from an observer is its
a. relative velocity.     b. proper motion.     c. radial velocity.     d. space velocity.     e. transverse velocity.

15. The size of a single star can be determined if we know its absolute magnitude and its
a. distance.     b. temperature.     c. proper motion.     d. radial velocity.     e. space velocity.

16. Over 2000 years ago the astronomer ___________ made a catalog of stars and divided them into classes of brightness.

17. A difference of 5 magnitudes corresponds to a factor of _____________ in apparent brightness.

18. A +3 magnitude star will be about ____________ times more luminous than a +5 magnitude star at the same distance.

19. The _____________ of a star is 1/2 the angular distance the star seems to move when observed from the ends of a baseline of 1 A.U.

20. The _______________ of a star is its apparent movement across the sky with respect to other stars.

21. One ______________ is the distance of a star whose parallax is one arc second.

22. The ____________ of a star is the total amount of energy it gives off per second.

23. A(n) ______________ star is one whose luminosity is greater than that of dwarf stars of the same spectral class.

24. A white dwarf is ______________ than a main sequence dwarf of the same spectral type.

25. ______________ has the largest known proper motion of any star.