Earl of Londonderry extinct on the death of his great-grandson, the fourth Earl, in 1714. The second creation came in 1726 in favour of the soldier and politician Thomas Pitt, 1st Baron Londonderry. He had already been created Baron Londonderry in 1719 and was made Viscount Gallen-Ridgeway at the same time as he was granted the earldom, also in the Peerage of Ireland. He was the husband of Lady Frances Ridgeway, daughter and heiress of the fourth Earl of the first creation. A member of the prominent Pitt family, he was the uncle of William Pitt, 1st Earl of Chatham. His younger son,
1766 Slipher of the planets for a period of more than half a century. The lunar and Martian Slipher craters were also named after the two brothers. The official naming citation was published by the Minor Planet Center before November 1977 (). 1766 Slipher 1766 Slipher, provisional designation , is a Paduan asteroid from the central regions of the asteroid belt, approximately 18 kilometers in diameter. It was discovered on 7 September 1962, by astronomers of the Indiana Asteroid Program at Goethe Link Observatory in Indiana, United States. The asteroid was named after American astronomers Vesto Slipher and his brother Earl C.