Ariel 1 (also known as UK-1 and S-55), was the first Britishsatellite, and the first satellite in the Ariel programme. Its launch in 1962 made the United Kingdom the third country to operate a satellite, after the Soviet Union and the USA. It was constructed in the United States by NASA, under an agreement reached as the result of political discussions in 1959 and 1960.
In late 1959, the Science and Engineering Research Council proposed the development of Ariel 1 to NASA, following an offer made by the United States at a meeting of the Committee on Space Research to provide assistance to other countries with the development and launch of scientific spacecraft. By early the following year the two countries had decided upon terms for the programme's scope and which organisations would be responsible for which parts of the programme.
Construction of the satellite occurred at the Goddard Space Flight Center. SERC provided the experiments, conducted operations, and later analysed and interpreted the results. Six experiments were carried aboard the satellite. Five of these examined the relationship between two types of solar radiation and changes in the Earth's ionosphere. They took advantage of techniques developed in the Skylark programme.