American astronomer (1891-1972) who, though he had no formal education, was hired at Mount Wilson Observatory in 1919. He assisted Edwin Hubble in formulating Hubble's law, and discovered Comet C/1961 R1 (Humason). The Humason crater on the moon is named after him, as are 'Humason-Zwicky stars.' TLS, one page, 7.5 x 12, Mount Wilson and Palomar Observatories letterhead, October 1, 1957. Letter to Cambridge astronomer F. J. M. Stratton, in part: "It is indeed a great honor to have been elected a Foreign Associate of the Royal Astronomical Society, and nothing could have pleased me more at this time. As you may know, I retired on the first of last July and am now occupying the desk so long used by Dr. Adams at the Hale Observatory. Dr. Harold Babcock is also here and continues to make daily observations on the sun. It is a pleasure to be here with him…After careful inspection of the Nova Herculis spectra, I believe you are correct in assuming that H8, 9, 10, 11 are present and that the other lines you mention are double. They certainly appear so to me. If you would like to make a personal inspection of the spectra, I shall gladly forward them to you." In fine condition, with intersecting folds.
