Astronomical observations have undergone a tremendous transformation as a result of the digital computer revolution, with a concomitant increase in the complexity of the effort required to extract useful information from that data. This course will introduce techniques of obtaining and analyzing astronomical data. We will begin by learning about celestial coordinates, basic spherical trigonometry, and time, and move on to discussion of CCD detectors, signal statistics, and the data reduction process, making use of data we obtain with our rooftop observing facilities, including a 24" telescope and radio telescope, as well as data from telescopes at the National Optical Astronomy Observatories. Students will analyze images and spectra using data reduction techniques standard among astronomers. Format: lecture/discussion, plus computer work and observing. Evaluation will be based on weekly problem sets, an hour test and a final observing project. Prerequisites: Astronomy 111 (or Astronomy 101 and either 102 or 104 with permission of instructor) and Mathematics 105or 106. Prior experience with UNIX is helpful, but not required. Enrollment limit: 10 (expected: 8).