Dirk Reuyl (1906 – 1972) was a

Dutch Dutch or Nederlands commonly refers to: * Something of, from, or related to the Netherlands ** Dutch people as an ethnic group () ** Dutch nationality law, history and regulations of Dutch citizenship () ** Dutch language () * In specific terms, i ...

American American(s) may refer to: * American, something of, from, or related to the United States of America, commonly known as the "United States" or "America" ** Americans, citizens and nationals of the United States of America ** American ancestry, p ...

physicist A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate cau ...

and

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

. He was the cousin of astronomer

Peter van de Kamp Piet van de Kamp (December 26, 1901 – May 18, 1995), known as Peter van de Kamp in the United States, was a Dutch astronomer who lived in the United States most of his life. He was professor of astronomy at Swarthmore College and director of ...

Life

Like his cousin, Reuijl (later "Reuyl") was born in

Kampen, Overijssel Kampen () is a List of cities in the Netherlands by province, city and List of municipalities of the Netherlands, municipality in the Provinces of the Netherlands, province of Overijssel, Netherlands. A member of the former Hanseatic League, it is ...

. He studied physics and mathematics at

Utrecht University Utrecht University (UU; , formerly ''Rijksuniversiteit Utrecht'') is a public university, public research university in Utrecht, Netherlands. Established , it is one of the oldest universities in the Netherlands. In 2023, it had an enrollment of ...

, where, in October 1931, he defended his PhD dissertation "Photographic measures of close double stars" with

Albertus Antonie Nijland Albertus (Albert) Antonie Nijland (30 October 1868 – 18 August 1936) was a Dutch astronomer. He was professor of astronomy at the Utrecht University, Rijksuniversiteit Utrecht, and served as director of the ''Sterrewacht Sonnenborgh'' (now ...

as advisor. He came to the United States a few years before Van de Kamp. He joined the staff at

McCormick Observatory The Leander McCormick Observatory is one of the astronomical observatories operated by the Department of Astronomy of the University of Virginia, and is situated just outside Charlottesville, Virginia (US) in Albemarle County on the summit of ...

in 1929 and continued to work there until 1944. He originally worked on the

parallax Parallax is a displacement or difference in the apparent position of an object viewed along two different sightline, lines of sight and is measured by the angle or half-angle of inclination between those two lines. Due to perspective (graphica ...

star A star is a luminous spheroid of plasma (physics), plasma held together by Self-gravitation, self-gravity. The List of nearest stars and brown dwarfs, nearest star to Earth is the Sun. Many other stars are visible to the naked eye at night sk ...

s, first publishing a list of 50 measurements in 1929 with fellow staff member Alexander N. Vyssotsky. In 1941 he measured angular diameter of ''

Mars Mars is the fourth planet from the Sun. It is also known as the "Red Planet", because of its orange-red appearance. Mars is a desert-like rocky planet with a tenuous carbon dioxide () atmosphere. At the average surface level the atmosph ...

'' using photographic plates.

Claim of planets

In 1943 he claimed to have discovered (with Erik Holberg) a ''planetary companion'' of the star system ''

70 Ophiuchi 70 Ophiuchi (p Ophiuchi) is a binary star, binary star system located 16.7 light-years away from the Earth. It is in the constellation Ophiuchus. At apparent magnitude, magnitude 4 it appears as a dim star visible to the unaided eye aw ...

'' and other stars. He claimed that this ''planetary object'' had 10 times the mass of the planet ''

Jupiter Jupiter is the fifth planet from the Sun and the List of Solar System objects by size, largest in the Solar System. It is a gas giant with a Jupiter mass, mass more than 2.5 times that of all the other planets in the Solar System combined a ...

'' and a 17-year orbital period. This caused quite a sensation at the time. A critical analysis by Wulff Heintz later discredited these claims.

Later life and death

In 1944 he left

and became head of the Photographic Division at the

Ballistic Research Laboratory The Ballistic Research Laboratory (BRL) was a research facility under the U.S. Army Ordnance Corps and later the U.S. Army Materiel Command that specialized in ballistics as well as vulnerability and lethality analysis. Situated at Aberdeen Pr ...

of the

U.S. Army The United States Army (USA) is the primary land service branch of the United States Department of Defense. It is designated as the Army of the United States in the United States Constitution.Article II, section 2, clause 1 of the United Stat ...

Aberdeen Proving Ground Aberdeen Proving Ground (APG) is a U.S. Army facility located adjacent to Aberdeen, Harford County, Maryland, United States. More than 7,500 civilians and 5,000 military personnel work at APG. There are 11 major commands among the tenant units, ...

Aberdeen, Maryland Aberdeen is a city located in Harford County, Maryland, United States, northeast of Baltimore. The population was 16,254 at the 2020 United States census. Aberdeen is the largest municipality in Harford County. Aberdeen is part of the Baltimo ...

. He wrote a 1949 article for

Sky and Telescope ''Sky & Telescope'' (''S&T'') is a monthly magazine covering all aspects of amateur and professional astronomy, including what to see in the sky tonight and new findings in astronomy. Other topics covered include: *observing guides for planets, ...

guided missiles A missile is an airborne ranged weapon capable of self-propelled flight aided usually by a propellant, jet engine or rocket motor. Historically, 'missile' referred to any projectile that is thrown, shot or propelled towards a target; this u ...

. During the late 1940s and the 1950s he worked on optically tracking the launch and trajectory of captured

V-2 rocket The V2 (), with the technical name ''Aggregat (rocket family), Aggregat-4'' (A4), was the world's first long-range missile guidance, guided ballistic missile. The missile, powered by a liquid-propellant rocket engine, was developed during the S ...

s. In 1957 Reuyl began a project for the optical tracking of the first artificial Earth satellites for the

International Geophysical Year The International Geophysical Year (IGY; ), also referred to as the third International Polar Year, was an international scientific project that lasted from 1 July 1957 to 31 December 1958. It marked the end of a long period during the Cold War w ...

. This project was in association with the

Smithsonian Astrophysical Observatory The Smithsonian Astrophysical Observatory (SAO) is a research institute of the Smithsonian Institution, concentrating on Astrophysics, astrophysical studies including Galactic astronomy, galactic and extragalactic astronomy, cosmology, Sun, solar ...

and tracked the first satellites launched by the U.S and

Soviet Union The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...

. Reuyl remained associated with Aberdeen through the 1960s. He died in 1972.

Honors and awards

Reuyl Crater, an

impact crater An impact crater is a depression (geology), depression in the surface of a solid astronomical body formed by the hypervelocity impact event, impact of a smaller object. In contrast to volcanic craters, which result from explosion or internal c ...

, was named in his honor.

References

{{DEFAULTSORT:Reuyl, Dirk 1906 births 1972 deaths 20th-century American astronomers 20th-century Dutch astronomers People from Kampen, Overijssel University of Virginia faculty Utrecht University alumni 20th-century American physicists Dutch emigrants to the United States