John August Anderson (August 7, 1876 – December 2, 1959) was an American

astronomer An astronomer is a scientist in the field of astronomy who focuses their studies on a specific question or field outside the scope of Earth. They observe astronomical objects such as stars, planets, natural satellite, moons, comets and galaxy, g ...

. He was born in

Rollag Rollag is a Municipalities of Norway, municipality in the traditional and electoral district Buskerud in Viken (county), Viken Counties of Norway, county, Norway. It is part of the Districts of Norway, traditional region of Numedal. The admini ...

, a small community in

Clay County, Minnesota Clay County is a county in the U.S. state of Minnesota. As of the 2020 census, the population was 65,318. Its county seat is Moorhead. Clay County is part of the Fargo, ND-MN Metropolitan Statistical Area. History The county was formed on ...

to the south of Hawley.

Biography

Anderson received his

Ph.D. A Doctor of Philosophy (PhD, Ph.D., or DPhil; Latin: or ') is the most common degree at the highest academic level awarded following a course of study. PhDs are awarded for programs across the whole breadth of academic fields. Because it is ...

Johns Hopkins University Johns Hopkins University (Johns Hopkins, Hopkins, or JHU) is a private university, private research university in Baltimore, Maryland. Founded in 1876, Johns Hopkins is the oldest research university in the United States and in the western hem ...

in 1907, and remained on the staff after graduation. In 1908, he became professor of astronomy at the university. In 1909, he was also given the responsibility for the Rowland ruling engines that were used for creating

diffraction grating In optics, a diffraction grating is an optical component with a periodic structure that diffracts light into several beams travelling in different directions (i.e., different diffraction angles). The emerging coloration is a form of structura ...

s, and the quality of these was considered excellent, especially the concave gratings. In 1916, he left to work at the

Mt. Wilson observatory The Mount Wilson Observatory (MWO) is an astronomical observatory in Los Angeles County, California, United States. The MWO is located on Mount Wilson, a peak in the San Gabriel Mountains near Pasadena, northeast of Los Angeles. The observ ...

. He remained on the Mt. Wilson staff until 1956. His most notable contribution was his adaptation of the Michelson's interferometer technique for measuring close

double star In observational astronomy, a double star or visual double is a pair of stars that appear close to each other as viewed from Earth, especially with the aid of optical telescopes. This occurs because the pair either forms a binary star (i.e. a bi ...

s. He used a rotating mask at the focus to measure the separation of

Capella Capella is the brightest star in the northern constellation of Auriga. It has the Bayer designation α Aurigae, which is Latinised to Alpha Aurigae and abbreviated Alpha Aur or α Aur. Capella is the sixth-brightest star i ...

. In the 1920s, he collaborated with

Harry O. Wood Harry Oscar Wood (1879–1958) was an American seismologist who made several significant contributions in the field of seismology in the early twentieth-century. Following the 1906 earthquake in San Francisco, California, Wood expanded his backgr ...

to develop a of

seismograph A seismometer is an instrument that responds to ground noises and shaking such as caused by earthquakes, volcanic eruptions, and explosions. They are usually combined with a timing device and a recording device to form a seismograph. The output ...

. From 1928 until 1948, he was Executive Officer of the

Caltech The California Institute of Technology (branded as Caltech or CIT)The university itself only spells its short form as "Caltech"; the institution considers other spellings such a"Cal Tech" and "CalTech" incorrect. The institute is also occasional ...

Observatory Council, working on the instrument and optical design of the main

Palomar Observatory Palomar Observatory is an astronomical research observatory in San Diego County, California, United States, in the Palomar Mountain Range. It is owned and operated by the California Institute of Technology (Caltech). Research time at the observat ...

telescope A telescope is a device used to observe distant objects by their emission, absorption, or reflection of electromagnetic radiation. Originally meaning only an optical instrument using lenses, curved mirrors, or a combination of both to observe ...

. During this period he collaborated closely with George E. Hale and the

Rockefeller Foundation The Rockefeller Foundation is an American private foundation and philanthropic medical research and arts funding organization based at 420 Fifth Avenue, New York City. The second-oldest major philanthropic institution in America, after the Carneg ...

. He died at the age of 83 in

Altadena, California Altadena () ("Alta", Spanish for "Upper", and "dena" from Pasadena) is an unincorporated area and census-designated place in the Verdugo Mountains region of Los Angeles County, California, approximately 14 miles (23 km) from the downtown ...

. The crater

Anderson Anderson or Andersson may refer to: Companies * Anderson (Carriage), a company that manufactured automobiles from 1907 to 1910 * Anderson Electric, an early 20th-century electric car * Anderson Greenwood, an industrial manufacturer * Anderson ...

on the

Moon The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width of ...

is named in his memory. He was awarded the

Franklin Institute The Franklin Institute is a science museum and the center of science education and research in Philadelphia, Pennsylvania. It is named after the American scientist and statesman Benjamin Franklin. It houses the Benjamin Franklin National Memori ...

Howard N. Potts Medal The Howard N. Potts Medal was one of The Franklin Institute Awards for science and engineering award presented by the Franklin Institute of Philadelphia, Pennsylvania. It is named for Howard N. Potts. The first Howard N. Potts Medal was awarded in ...

in 1924.

Bibliography

Unless otherwise noted, the following publications were by John A. Anderson. * "On the Application of the Laws of Refraction in Interpreting Solar Phenomena", Astrophysical Journal, vol. 31, 1910. * "A method of investigating the Stark effect for metals, with results for chromium", 1917. * "The vacuum spark spectrum of calcium", 1924. * "The Use of Long Focus Concave Gratings at Eclipses", ''Publications of the Astronomical Society of the Pacific'', Vol. 38, 1926. * J. A. Anderson and

Russell W. Porter Russell Williams Porter (December 13, 1871 – February 22, 1949) was an American artist, engineer, amateur astronomer and Arctic explorer. He was a pioneer in the field of “cutaway illustration" and is sometimes referred to as the "founder" or ...

, "Ronchi's Method of Optical Testing", Astrophysical Journal, vol. 70, 1929. * "Spectral energy-distribution of the high-current vacuum tube", 1932. * "On the application of Michelson's interferometer method to the measurement of close double stars", ''Astrophysical Journal'', vol. 51, June 1920. * "Optics of the 200-inch Hale Telescope", ''Publications of the Astronomical Society of the Pacific'', Vol. 60, 1948.

References

{{DEFAULTSORT:Anderson, John August 1876 births 1959 deaths American astronomers Johns Hopkins University alumni Johns Hopkins University faculty Members of the United States National Academy of Sciences