discovered a new planet—which was named Pluto on May 1. Putnam's political and business interests lessened the amount of time he could devote to the Lowell Observatory in the 1930s and 1940s. The Observatory's three senior astronomers—V. M. Slipher, E. C. Slipher and C. O. Lampland—were no longer doing much research or publishing and prevented other, younger astronomers from using the telescopes. Lampland died on December 14, 1951, and Putnam decided to use the occasion to bring in some new blood. Putnam hired Albert Wilson, a Caltech astronomer who had led the Palomar Sky Survey. Although Wilson clashed with Observatory personnel and resigned after only two years on the job, with Putnam's support he greatly modernized the Observatory's procedures, policies, and equipment. Most importantly, he instituted a mandatory retirement age of 70 and resilvered the Observatory's Ritchey–Chrétien telescope (now named the John Hall Telescope). When Wilson came under attack for laying off photoelectric research staff, Putnam publicly reaffirmed his confidence in him. As Putnam searched for a new director, he almost put the Lowell Observatory under the control of Harvard University. Donald Menzel, director of the Harvard Observatory, offered to move Harvard's telescope to the Lowell Observatory in exchange for naming the next director. Putnam was initially receptive to the idea, but after consulting with several young astronomers (most notably Harold Johnson), Putnam decided against a collaboration with Harvard. Determined to continue the modernization program begun by Wilson, Putnam hired astronomer John Scoville Hall as director in 1958. Hall took advantage of the launch of Sputnik 1 in October 1957 and the ensuing Sputnik crisis in the United States to seek greatly increased federal funding for the Observatory. Putnam used his extensive political connections to help Hall land lucrative federal contracts, which significantly improved the Observatory's finances. Hall also hired energetic, bright young astronomers and rebuilt the Observatory's reputation as a research institution. In 1961, Putnam managed to make an indirect contribution to the study of Mars. E. C. Slipher had taken an enormous number of photographs of Mars, but most of them remained unseen by others. Determined to restore the Observatory's prestige, Putnam badgered Slipher into making these images available. In 1962, Slipher's monumental work, A Photographic History of Mars (1905–1961), was published, marking a major advance in the planetary science of Mars. Putnam also played a major role in securing a new telescope for the Observatory in 1961.