| A | B |
|---|
| blue | Stars of this color have the highest surface temperature |
| white dwarf | Which remnant is left over when a low or medium mass star runs out of energy and dies? |
| red | Stars of this color have the coolest surface temperature |
| 9.5 trillion | A light year is _______ kilometers. |
| light-years | Stellar distances are usually expressed in what units? |
| magnitude | Measure of a star's brightness |
| Star B | If Star A if farther from Earth than star B and both stars have the same absolute magnitude, which has the greater apparent magnitude? |
| -5 or -10 | According to the H-R diagram, which magnitude would be associated with the brightest star? (Hint: answer is __ OR __) |
| temperature & absolute magnitude | A Hertzspung-Russel (H-R) diagram shows the relationship between ____ & ____. |
| main sequence | A star spends about 90% of its life in this stage of development. |
| Red | These main-sequence stars are the most massive. |
| Blue | These main-sequence stars are the least massive. |
| the hottest | According to the H-R diagram, whch main sequence stars are brightest? |
| 5 | According to the H-R diagram, the sun has an absolute magnitude of about ____. |
| nebula | Interstellar matter that will eventually form a star. |
| protostar temperature nuclear fusion | A star is said to be born when a _____ reaches a ____ high enough for ____ ____ to occur. |
| gravity | This force is most responsible for the formation of a star. |
| supernova | Massive stars terminate in a brilliant explosion called a _____. |
| fuel collapse | All stars, regardless of size, eventually run out of ___ and ____. |
| red giant | When a main-sequence star has exhausted the fuel in its core, it becomes a ____ ____. |
| main-sequence star | The sun is currently classified as a: |
| red giant | What is the next stage in the sun's life cycle? |
| spiral | Which type of galaxy is made up of both old and young stars? |
| black hole | Light cannot escape the intense gravitational pull of a ____ ____. |
| Milky Way | Our galaxy is called the: |
| one of the spiral arms | Where is our sun located in the Milky Way? |
| elliptical | About 60% of all known galaxies are classified as ____ galaxies. |
| 14 billion | According to the big bang theory, the universe began about ___ _____ years ago. |
| Which object is largest: constellation, galaxy, star, or planet? | galaxy |
| irregular | Which type of galaxy is made up of mostly young stars? |
| irregular | This type of galaxy lacks symmetry in its appearance. |
| constellations | Patterns of stars that were originally named in honor of mythological characters or great heroes. |
| low mass star | Which star does not usually form a red giant? |
| massive star | Which star blows up in a supernova event? |
| irregular galaxies | About 30% of all known galaxies are classified as: |
| absolute magnitude | Actual brightness of a star: |
| yellow | Stars with a surface temperature between 5000 K and 6000 K appear: |
