John Fillmore Hayford (May 19, 1868 – March 10, 1925) was an eminent United States geodesist. His work involved the study of isostasy and the construction of a reference ellipsoid for approximating the figure of the Earth. Hayford was elected to the United States National Academy of Sciences in 1911 and the American Philosophical Society in 1915.^[1][2] The crater Hayford on the far side of the Moon is named after him.^[3] Mount Hayford, a 1,871 m mountain peak near Metlakatla, Alaska, United States, is named after him.^[4] A biography of Hayford may be found in the Biographical Memoirs of the National Academy of Sciences, 16 (5), 1935.

• Hayford ellipsoid

• Hayford, JF (1917), "Gravity and Isostasy.", Science, 45 (1163) (published Apr 13, 1917): 350–354, doi:10.1126/science.45.1163.350, PMID 17795741
• Hayford, JF (1911), "The American Association for the Advancement of Science the Relations of Isostasy to Geodesy, Geophysics and Geology.", Science, 33 (841) (published Feb 10, 1911): 199–208, doi:10.1126/science.33.841.199, PMID 17815861
• Hayford, JF (1909), "The New College of Engineering, an Opportunity.", Science, 29 (753) (published Jun 4, 1909): 887–891, doi:10.1126/science.29.753.887, PMID 17817509
• Hayford, JF (1907), "Report of the General Secretary.", Science, vol. 25, no. 628 (published Jan 11, 1907), pp. 46–50, doi:10.1126/science.25.628.46, PMID 17771974
• Tittmann, OH; Hayford, JF (1906), "The Budapest Conference of the International Geodetic Association.", Science, 24 (623) (published Dec 7, 1906): 713–719, doi:10.1126/science.24.623.713, PMID 17836523
• Hayford, JF (1906), "Report of the General Secretary.", Science, 24 (602) (published Jul 13, 1906): 33–40, doi:10.1126/science.24.602.33, PMID 17811031
• Hayford, JF (1905), "A Connection by Precise Leveling Between the Atlantic and Pacific Oceans.", Science, 21 (539) (published Apr 28, 1905): 673–674, doi:10.1126/science.21.539.673, PMID 17789796
• Hayford, JF (1903), "The Longitude of Honolulu, Various Determinations, 1555-1903.", Science, 18 (462) (published Nov 6, 1903): 589–593, doi:10.1126/science.18.462.589, PMID 17812559
• Hayford, JF (1901), "A New Connection Between the Gravity Measures of Europe and of the United States.", Science, 13 (330) (published Apr 26, 1901): 654–655, doi:10.1126/science.13.330.654, PMID 17808951
• Hayford, JF (1901), "Recent Progress in Geodesy.", Science, 13 (323) (published Mar 8, 1901): 381–383, doi:10.1126/science.13.323.381, PMID 17801118
• Hayford, JF (1900), "Recent Progress in Geodesy.", Science, vol. 11, no. 271 (published Mar 9, 1900), pp. 369–374, doi:10.1126/science.11.271.369, PMID 17768837
• Hayford, JF (1899), "Section A--Astronomy and Mathematics.", Science, 10 (245) (published Sep 8, 1899): 331–333, doi:10.1126/science.10.245.331, PMID 17790921
• Hayford, JF (1898), "The Limitations of the Present Solution of the Tidal Problem.", Science, vol. 8, no. 206 (published Dec 9, 1898), pp. 810–814, doi:10.1126/science.8.206.810, PMID 17754918