This brief text is meant for use in an introductory astronomy course and explains concepts ranging from gravitation and the motion of the planets, to various planets and galaxies, to cosmology and astrobiology, addressing the underlying physical concepts for connecting astronomical observations to their theories. This edition has a new chapter on exoplanets; new coverage of the altazimuth coordinate system; revised coverage of planet classification; expanded coverage of the satellites of the planets; and scientific updates related to physics and astronomy, including the discovery of the Higgs boson, indications of water activity on Mars, observations of fragmentation of an asteroid and rings around another one, the meeting of the Rosetta spacecraft with Comet 67P/Churyumov-Gerasimenko, the discovery of new exoplanets, the sunspot cycle, the improved parallax measurements by Gaia and the Hubble Space Telescope, and new properties of the solar wind. Annotation ©2016 Ringgold, Inc., Portland, OR (protoview.com)