Name Date Directions: Match the vocabulary terms on the left with the definitions on the right. Terms Definitions 1. black hole a. the point in the sky that is directly over the head of the observer. 2. constellation b. a heavenly body that revolves around a planet or other larger body; moon. 3. asteroid 4. zenith 5. planet 6. orbit 7. moon c. a large, nonluminous celestial body, esp. one of the nine in the solar system, that revolves around a star and often has one or more satellites. d. the curved path in which a planet, satellite, or spacecraft revolves about another body. e. a system of billions of stars and other matter held relatively close to each other by gravity and separated from other such systems by vast distances. f. at a particular observation point, the blocking of light from one celestial body by another, such as the eclipse of the sun by the interposition of the moon, or the eclipse of the moon by the earth's coming between the sun and moon. g. a small mass, speck, or remnant of matter traveling through space or falling to earth, or the fiery streak in the sky made by the friction of its passage through the earth's atmosphere; meteorite or meteoroid. 8. meteor h. any planet's natural satellite. 9. satellite 10. eclipse 11. comet 12. meteorite 13. galaxy i. any of eighty-eight groupings or patterns of stars named after the animals, objects, or mythological characters they are thought to resemble. j. the force by which a planet or other such body tends to draw objects toward its center. k. a hypothetical region or body in space, possibly the remnants of a collapsed star, with such a strong gravitational pull that neither light nor matter can escape. l. a heavenly body orbiting the sun, and having a nucleus surrounded by a nebulous sheath that may form an elongated tail when the body comes close to the sun. m. any of thousands of celestial bodies with diameters between one and five hundred miles that revolve around the sun in orbits located mostly between those of Jupiter and Mars; planetoid. 14. gravity n. a mass of stone or metal falling to earth from outer space; meteoroid.
What you need to understand by the end of this unit: Vocabulary terms you will need to know by the end of this unit: The appearance of the lighted portion of the moon changes in a predictable cycle as a result of the relative positions of Earth, the moon, and the sun. Earth turns on an axis that is tilted relative to the plane of Earth s yearly orbit. The tilt causes sunlight to fall more intensely on different parts of the Earth during various parts of the year. The differences in heating of Earth s surface and length of daylight hours produce the seasons. The solar system consists of planets, moons, and other smaller objects including asteroids and comets that orbit the sun. Planets in the solar system differ in terms of their distance from the sun, number of moons, size, composition, and ability to sustain life. Every object exerts gravitational force on every other object depending on the mass of the objects and the distance between them. The sun s gravitational pull holds Earth and other planets in orbit. Earth s gravitational force holds the moon in orbit. The sun is one of billions of stars in the Milky Way galaxy, that is one of billions of galaxies in the universe. Scientists use a variety of tools to investigate the nature of stars, galaxies, and the universe. Historically, cultures have observed objects in the sky and understood and used them in various ways. telescope universe galaxy Milky Way galaxy star constellation solar system celestial object sun revolution orbits planets asteroids comets satellites axis of rotation Earth s tilt seasons reflection phases of the moon force mass gravity gravitational force distance scale speed of light light years