11. Look at the data in the table on page 334, which compares the planets in our solar system. a. Which planet has the largest mass? b. Which planets are the most similar to each other? Explain your answer. c. List the planets in order of increasing gravity. d. State a trend that you observe in the data.
Galaxies
A galaxy is a system of billions of stars. Galaxies differ in size based on the number of stars they contain.
Galaxies also differ in shape. Some galaxies have a spiral shape and others have an elliptical (oval) shape.
Planet Earth and our solar system are part of a galaxy called the Milky Way. Our solar system is in one of the spiral arms of this galaxy.
Astronomers can see billions of other galaxies in the universe using powerful telescopes, and they predict that there are many more galaxies yet to be discovered.