Judith Gamora Cohen (born 1946), is an American astronomer and the Kate Van Nuys Page Professor of

Astronomy Astronomy () is a natural science that studies celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and evolution. Objects of interest include planets, moons, stars, nebulae, g ...

at the

California Institute of Technology 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 ...

. She is a recognized expert regarding the

Milky Way Galaxy The Milky Way is the galaxy that includes our Solar System, with the name describing the galaxy's appearance from Earth: a hazy band of light seen in the night sky formed from stars that cannot be individually distinguished by the naked eye. ...

, particularly with respect to the Galaxy's outer halo. She also played a key role in the design and construction of the

Keck Telescope The W. M. Keck Observatory is an astronomical observatory with two telescopes at an elevation of 4,145 meters (13,600 ft) near the summit of Mauna Kea in the U.S. state In the United States, a state is a constituent political entit ...

Early life and education

Born in 1946, in

New York City, New York New York, often called New York City or NYC, is the List of United States cities by population, most populous city in the United States. With a 2020 population of 8,804,190 distributed over , New York City is also the L ...

, Cohen grew up in

Brooklyn Brooklyn () is a borough of New York City, coextensive with Kings County, in the U.S. state of New York. Kings County is the most populous county in the State of New York, and the second-most densely populated county in the United States, be ...

. Educated in the city's public schools, she also attended the Workmen's Circle schools in Brooklyn. The recipient of a

National Merit Scholarship The National Merit Scholarship Program is a United States academic scholarship competition for recognition and university scholarships administered by the National Merit Scholarship Corporation (NMSC), a privately funded, not-for-profit organizati ...

, she attended Radcliffe College, graduating from there in 1967 with a Bachelor of Arts degree in astronomy. In 1971, she was awarded a PhD in astronomy from the

(Caltech). Her dissertation, ''The lithium isotope ratio in F and G field stars'', was supervised by

Guido Münch Guido Münch Paniagua (June 9, 1921 – 29 April 2020) was a Mexican astronomer and astrophysicist. Biography Münch was born in San Cristobal de las Casas, Mexico. He studied civil engineering and mathematics at the National Autonomous Unive ...

Career and research

A Miller Postdoctoral Fellow at the

University of California, Berkeley The University of California, Berkeley (UC Berkeley, Berkeley, Cal, or California) is a public land-grant research university in Berkeley, California. Established in 1868 as the University of California, it is the state's first land-grant u ...

from 1971 to 1974, she was subsequently appointed as an assistant astronomer at the

Kitt Peak National Observatory The Kitt Peak National Observatory (KPNO) is a United States astronomical observatory located on Kitt Peak of the Quinlan Mountains in the Arizona-Sonoran Desert on the Tohono Oʼodham Nation, west-southwest of Tucson, Arizona. With more than ...

in Tucson, Arizona. Cohen joined the teaching faculty at Caltech in 1979, and was named the Kate Van Nuys Page professor of astronomy there in 2005. In addition, she serves as Caltech's co-chair of the Keck Science Steering Committee and is a member of the National Academy of Sciences. She has also delivered the

Caroline Herschel Caroline Lucretia Herschel (; 16 March 1750 – 9 January 1848) was a German born British astronomer, whose most significant contributions to astronomy were the discoveries of several comets, including the periodic comet 35P/Herschel–Rigolle ...

Distinguished Lecture at the

Space Telescope Science Institute The Space Telescope Science Institute (STScI) is the science operations center for the Hubble Space Telescope (HST), science operations and mission operations center for the James Webb Space Telescope (JWST), and science operations center for the ...

and the

Cecilia Payne-Gaposchkin Cecilia Payne-Gaposchkin (born Cecilia Helena Payne; – ) was a British-born American astronomer and astrophysicist who proposed in her 1925 doctoral thesis that stars were composed primarily of hydrogen and helium. Her groundbreaking conclus ...

Distinguished Lecture at the

Center for Astrophysics Center or centre may refer to: Mathematics * Center (geometry), the middle of an object * Center (algebra), used in various contexts ** Center (group theory) ** Center (ring theory) * Graph center, the set of all vertices of minimum eccentrici ...

Harvard University Harvard University is a private Ivy League research university in Cambridge, Massachusetts. Founded in 1636 as Harvard College and named for its first benefactor, the Puritan clergyman John Harvard, it is the oldest institution of high ...

. Cohen's research in the structure and evolution of stars and galaxies has included developing instrumentation for the

Keck observatory The W. M. Keck Observatory is an astronomical observatory with two telescopes at an elevation of 4,145 meters (13,600 ft) near the summit of Mauna Kea in the U.S. state of Hawaii. Both telescopes have aperture primary mirrors, and when co ...

and leading the Caltech Faint Galaxy Redshift Survey, with more than 200 published papers. Her research has also been described in the popular press. Using

laser A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The word "laser" is an acronym for "light amplification by stimulated emission of radiation". The fi ...

-guided

adaptive optics Adaptive optics (AO) is a technology used to improve the performance of optical systems by reducing the effect of incoming wavefront distortions by deforming a mirror in order to compensate for the distortion. It is used in astronomical tele ...

at the Keck observatory, she showed that several unlikely tight clusters of stars orbiting the

Andromeda Galaxy The Andromeda Galaxy (IPA: ), also known as Messier 31, M31, or NGC 224 and originally the Andromeda Nebula, is a barred spiral galaxy with the diameter of about approximately from Earth and the nearest large galaxy to the Milky Way. The gal ...

were not actually clusters at all. Together with Evan Kirby, she has studied the mass of nearby

dwarf galaxy A dwarf galaxy is a small galaxy composed of about 1000 up to several billion stars, as compared to the Milky Way's 200–400 billion stars. The Large Magellanic Cloud, which closely orbits the Milky Way and contains over 30 billion stars, is so ...

Triangulum II, showing that this galaxy has a surprisingly large mass for its number of visible stars, making it a candidate dark matter galaxy.

References

External links

Cohen's Website

Cohen's Research WebsiteTalk by Cohen
{{DEFAULTSORT:Cohen, Judith Gamora 1946 births Living people American women astronomers 20th-century American astronomers 21st-century American astronomers Radcliffe College alumni California Institute of Technology alumni California Institute of Technology faculty Planetary scientists Women planetary scientists

Early life and education

Career and research

See also

References

External links