Establishing a Seismometer at PARI and Designing a Switching Circuit Utilizing Fiber Communications

At Pisgah Astronomical Research Institute (PARI) in Rosman, NC I spent ten weeks as the first NC Space Grant/Cline Astronomy Scholar developing multiple projects that helped to establish PARI as a resource for the scientific community. The first project that I worked on was establishing PARI's seismometer which serves as a resource for the region and utilizes sensitive equipment to measure 2.8 magnitude earthquakes occurring anywhere on earth. After basic seismometer operating principles were studied, multiple locations were surveyed to find an ideal location with little ambient noise and no disturbance from human or mechanical sources. Disturbances were generated at several locations identified as potential sites for the seismometer at 10, 20 and 30 feet by dropping a basketball and by driving a car around the location in an established pattern. Noise response was analyzed using the WinSDR software package which generates digital records of analog seismometer data and an ideal location was identified. The second project involved designing a circuit around the specific needs of the PARI optical telescope ridge. This ridge is susceptible to equipment that is damaged or improperly reset due to lightning. The circuit utilized the insulated properties of optical fiber to transmit a switching signal to the weather stations on the PARI optical ridge. This signal reset those stations that transmitted asynchronously after a lightning strike. Fiber optic transmitters were incorporated into the circuit along with TTL logic to provide a solid system that met the necessary specifications. After a rewarding an interesting summer I will follow up on my work next year for ten more weeks.