NEWS RELEASE, 6/11/96 Student-built rooftop radio observatory now centerpiece of innovative radio astronomy course at UC Berkeley

by Robert Sanders

Berkeley -- Neither rain nor fog nor city lights plague an avid group of undergraduate astronomers at the University of California at Berkeley. They've switched from optical astronomy -- telescope observations all too often washed out by street lights or obscured by clouds -- to radio astronomy, tuning in to radio waves from distant objects that easily penetrate clouds and are unaffected by city lights. To achieve this the students built an inexpensive radio telescope atop the astronomy building in the middle of the 30,000-student UC Berkeley campus, a mere 10 miles from downtown San Francisco. It has become the centerpiece of an innovative upper-level course in radio astronomy. Its plywood mount and pop rivets may look low-tech, but the aluminum microwave horn -- standing about 6 feet high -- is equipped with high-tech electronic detectors. Costing a mere $20,000, the telescope is a testament to the ingenuity and innovation undergraduate students can bring to teaching. "The students can see all the pieces, play with them, put them together and really understand what's going on," said senior Raghuveer Parthasarathy, who helped assemble the instrument and now is a teaching assistant for the class. "They can develop technical skills applicable to all sorts of things, not just astronomy." Curtis Frank, who received his B.S. in mechanical engineering from UC Berkeley in 1992, and Parthasarathy, a physics and astrophysics major, will discuss the philosophy behind the course June 10 at a session on college-level astronomy courses at the June 9 to 13 meeting of the American Astronomical Society in Madison, Wisconsin. They hope to encourage other institutions to consider radio astronomy as an educational possibility. "We'd really like to stimulate other departments to jazz up their lab classes like this," said David Cudaback, a retired astronomy department lecturer still active in teaching the course. "Every department has a group of undergraduates that could do something on the same level as this." In the new course, organized by UC Berkeley professor of astronomy Carl Heiles, students are given all the electronic components they need -- unassembled-- and encouraged to experiment with different arrangements to obtain a working telescope. Organized into research groups, the students first experiment with each of the individual components, learning about fundamental theories in microwave electronics and signal processing, and then move on to using the system as a whole to make astronomical observations. To date, the students have observed a supernova supershell, measured the rotation curve of the Milky Way galaxy and derived its mass. The system also can be used to observe OH (hydroxyl) masers in the galaxy. Students can take a simple hydrogen spectrum in a matter of seconds. The effectiveness of such a small telescope comes from the fact that hydrogen is abundant in the galaxy, making a large telescope unnecessary, Cudaback said. "Students really learn how to work with other people on a project," said Robyn Millan, one of the undergraduates who built the telescope. Millan just graduated with an A. B. in physics and astrophysics and will attend graduate school at UC Berkeley. The radio telescope and radiolab are part of a growing excitement and intensity to enhance undergraduate education in astronomy at UC Berkeley. The new class, Astronomy 120B, was taught for the first time during the fall 1995 semester, and was a great success, according to one student who took the course, Jeremy Bramson. "This is the best class I ever took," said the fifth-year senior, an astrophysics major in the astronomy department. An earlier version of the class won the campuswide Educational Initiatives Award in the spring of 1995 from the Academic Senate Committee on Teaching. In awarding the prize, they praised the laboratory course for its "fresh ideas about the use of students' time." The Donna and Darwin Poulos Fund, established by a former graduate of the astronomy department with a matching donation from her employer Johnson & Johnson, paid the way for the students to attend the AAS meeting in Wisconsin. ###