21.1 Quiz Structure of the Solar System

Mercury Venus Earth Mars Jupiter Saturn Uranus Neptune Multiple Choice 1. An object that orbits the Sun, has a spherical shape, and has a mass greater than the mass of other objects near it is a(n).... star. planet. asteroid. 2. What keeps planets in orbit around the Sun? the Sun's mass the Sun's period of rotation the Sun's gravitational force 3. The planets in the solar system are so far apart that scientists measure the distances between them in.... miles. kilometers. astronomical units. Matching comet object made of gas, dust, and ice star type of object at the center of the solar system period of rotation the time it takes an object to spin once period of revolution the time it takes an object to travel around the Sun asteroids small, rocky objects that orbit the Sun between Mars and Jupiter outer planets large spherical objects made primarily of the gases hydrogen and helium inner planets spherical objects made mainly of solid, rocky materials