Tel Aviv University and entered a pre-academic course, completing his matriculation, then began studying physics. During this period, he worked in a variety of places, including in a bakery and retirement home. After failing two exams at the end of his first year and realizing that the full-time work he needed to do to pay his tuition interfered with his studies, Vanunu suspended his studies and returned to his parents' home in Beersheba, where he found temporary work. Negev Nuclear Research Center In 1976, Vanunu applied for a job at the Negev Nuclear Research Center, an Israeli facility used to develop and manufacture nuclear weapons located in the Negev Desert south of Dimona. Most worldwide intelligence agencies estimate that Israel developed nuclear weapons as early as the 1960s, but the country has intentionally maintained a "nuclear ambiguity", neither acknowledging nor denying that it possesses nuclear weapons. Vanunu had heard from a friend of his brother Meir that well-paying jobs were being advertised by the facility. After a lengthy interview with the facility's security officer, he was accepted for training. He signed a contract forbidding disclosure of sensitive security materials and had to promise not to visit any Arab or Communist countries for five years after his employment at the facility ended. He passed health checks, after which his training began. He was put through an intensive training course in physics, chemistry, mathematics, first aid, fire drill, and English. He did sufficiently well to be accepted and was employed as a nuclear plant technician and shift manager in February 1977. Vanunu earned a high salary by Israeli standards, and lived well. His work record was so good he qualified for a car and telephone allowance, though he had no interest in either and simply had his brother Meir's car registered in his name and had the telephone installed at his parents’ house. In 1979, he enrolled at Ben-Gurion University of the Negev in Beersheba. Initially, he wanted to study engineering, but within a week switched to economics, and also began a Greek philosophy course. In the autumn of 1980, he took a backpacking trip through Europe. He toured London, Amsterdam, Germany, and Scandinavia, and then visited Greece and toured the Greek islands with a Canadian friend. After returning to Israel, he bought a flat in Beersheba. In the summer of 1983, he took a three-month trip to the United States and