spectrum. It proposed frequencies and a set of initial targets. In 1960, Cornell University astronomer Frank Drake performed the first modern SETI experiment, named "Project Ozma" after the Queen of Oz in L. Frank Baum's fantasy books. Drake used a radio telescope in diameter at Green Bank, West Virginia, to examine the stars Tau Ceti and Epsilon Eridani near the 1.420 gigahertz marker frequency, a region of the radio spectrum dubbed the "water hole" due to its proximity to the hydrogen and hydroxyl radical spectral lines. A 400 kilohertz band around the marker frequency was scanned using a single-channel receiver with a bandwidth of 100 hertz. He found nothing of interest. Soviet scientists took a strong interest in SETI during the 1960s and performed a number of searches with omnidirectional antennas in the hope of picking up powerful radio signals. Soviet astronomer Iosif Shklovsky wrote the pioneering book in the field, Universe, Life, Intelligence (1962), which was expanded upon by American astronomer Carl Sagan as the best-selling book Intelligent Life in the Universe (1966). In the March 1955 issue of Scientific American, John D. Kraus described an idea to scan the cosmos for natural radio signals using a flat-plane radio telescope equipped with a parabolic reflector. Within two years, his concept was approved for construction by Ohio State University. With a total of US$71,000 () in grants from the National Science Foundation, construction began on an plot in Delaware, Ohio. This Ohio State University Radio Observatory telescope was called "Big Ear". Later, it began the world's first continuous SETI program, called the Ohio State University SETI program. In 1971, NASA funded a SETI study that involved Drake, Barney Oliver of Hewlett-Packard laboratories, and others. The resulting report proposed the construction of an Earth-based radio telescope array with 1,500 dishes known as "Project Cyclops". The price tag for the Cyclops array was US$10 billion. Cyclops was not built, but the report formed the basis of much SETI work that followed. The Ohio State SETI program gained fame on August 15, 1977, when Jerry Ehman, a project volunteer, witnessed a startlingly strong signal received by the telescope. He quickly circled the indication on a printout and scribbled the exclamation "Wow!" in the margin. Dubbed the Wow! signal, it is considered by some to be the best candidate for a radio signal from an artificial, extraterrestrial source ever discovered, but it has not