1. When using the scientific method, a hypothesis that would explain a particular observation
-must be able to be tested.
2. The number 384,000,000 can also be written as
3. Compared to other stars, we find the Sun remarkable because
1. Most of our galaxy is made up of:
2. A globular cluster is:
-a cluster of hundreds of thousands of stars found in our own galaxy.
3. It is difficult to devise a model of the Milky Way based on observations of the sky because:
1. S0 galaxies are:
-disklike with no spiral arms.
2. Hubbles classification separates what kinds of galaxies?
-spiral and elliptical
3. Besides shape, spiral and elliptical galaxies differ in:
-composition and temperature of their gases.
1. A space ship traveling at one-half the speed of light (0.5c) beams a laser from its front. If you are
outside of the ship and measured the speed of the laser, what would be the result?
2. Light coming from the surface of a massive obje
1. The composition of a main-sequence star changes most dramatically at its:
2. A star must continually balance:
-inward gravity with outward pressure.
3. A mass transfer can occur between two stars when:
-the Roche lobe of one completely
1. Sunspots are:
temporary features on the photosphere.
2. An aurora is the result of an interaction between:
energetic particles from the Sun and magnetism of Earth.
3. Nuclear fusion is a process in which:
two nuclei combine to become a large
1. Evidence that many stars form from the same cloud is the existence of:
2. Which of the following molecules would not be found in a molecular cloud?
3. The most abundant element in the universe is:
1. The largest diameter stars that we see are known as:
2. On an H-R diagram, the most luminous stars are always found at the
3. A parsec is a measure of:
4. Spectral types are used to classify stars according
1. From the absorption lines in the spectrum of a cloud, it is possible to determine the
-type of atoms in the cloud.
2. Astronomical object A is more luminous than astronomical object B, but both these objects are exactly
the same in diameter.
1. The average distance between the Sun and the Earth
-is an astronomical unit (AU).
2. In six months, you will be able to see a different set of stars in the night sky because
-Earth will move.
3. If Earth's axis were tilted twice as much as it
1. Looking at distant objects:
-allows us to look back in time.
2. To directly measure a distance to a distant galaxy, you would be most likely to use:
-the standard candle of a Type I supernova.
3. A standard candle is:
-an object for which th