Ellen Dorrit Hoffleit (March 12, 1907 – April 9, 2007) was an American senior research

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 ...

Yale University Yale University is a Private university, private Ivy League research university in New Haven, Connecticut, United States. Founded in 1701, Yale is the List of Colonial Colleges, third-oldest institution of higher education in the United Stat ...

. She is best known for her work in

variable star A variable star is a star whose brightness as seen from Earth (its apparent magnitude) changes systematically with time. This variation may be caused by a change in emitted light or by something partly blocking the light, so variable stars are ...

astrometry Astrometry is a branch of astronomy that involves precise measurements of the positions and movements of stars and other Astronomical object, celestial bodies. It provides the kinematics and physical origin of the Solar System and this galaxy, th ...

spectroscopy Spectroscopy is the field of study that measures and interprets electromagnetic spectra. In narrower contexts, spectroscopy is the precise study of color as generalized from visible light to all bands of the electromagnetic spectrum. Spectro ...

meteors A meteor, known colloquially as a shooting star, is a glowing streak of a small body (usually meteoroid) going through Earth's atmosphere, after being heated to incandescence by collisions with air molecules in the upper atmosphere, creating a ...

, and the

Bright Star Catalog The Bright Star Catalogue, also known as the Yale Catalogue of Bright Stars, Yale Bright Star Catalogue, or just YBS, is a star catalogue that lists all stars of stellar magnitude 6.5 or brighter, which is roughly every star visible to the nak ...

. She is also known for her mentorship of many young women and generations of astronomers.

Life

Hoffleit's interest in astronomy began with the 1919 Perseid meteor shower that she saw with her mother. In 1928, she graduated

cum laude Latin honors are a system of Latin phrases used in some colleges and universities to indicate the level of distinction with which an academic degree has been earned. The system is primarily used in the United States. It is also used in some Sout ...

with a B.A. in mathematics. She then went on to work for the

Harvard College Observatory The Harvard College Observatory (HCO) is an institution managing a complex of buildings and multiple instruments used for astronomical research by the Harvard University Department of Astronomy. It is located in Cambridge, Massachusetts, United St ...

, searching for variable stars. In 1938, she was awarded a Ph.D. in astronomy from

Radcliffe College Radcliffe College was a Women's colleges in the United States, women's Liberal arts colleges in the United States, liberal arts college in Cambridge, Massachusetts, that was founded in 1879. In 1999, it was fully incorporated into Harvard Colle ...

and was subsequently hired, in 1948, as an astronomer at

Harvard University Harvard University is a Private university, private Ivy League research university in Cambridge, Massachusetts, United States. Founded in 1636 and named for its first benefactor, the History of the Puritans in North America, Puritan clergyma ...

. She remained at Harvard until 1956 when she moved to

. She remained at Yale until retirement in 1975. At Yale she followed in the footsteps of

Ida Barney Ida Barney (November 6, 1886 – March 7, 1982) was an American astronomer, best known for her 22 volumes of astrometric measurements on 150,000 stars. She was educated at Smith College and Yale University and spent most of her career at the Ya ...

, taking over her astrometric work, and of whom she later wrote "To know erwas a pleasure, inspiration, and privilege, both at work and socially." Hoffleit also served as director of the Maria Mitchell Observatory on

Nantucket Island Nantucket () is an island in the state of Massachusetts in the United States, about south of the Cape Cod peninsula. Together with the small islands of Tuckernuck and Muskeget, it constitutes the Town and County of Nantucket, a combined cou ...

from 1957 to 1978, where she ran summer programs (May–October) for more than 100 students, many of whom went on to successful careers in astronomy. In her final years at Yale, Hoffleit taught basic courses in astronomy to undergraduates. Her passionate lectures in Davies Hall, usually with over 100 students, inspired and awed them. She engendered a lifelong interest in astronomy for young women and men, many of whom were just satisfying a prerequisite to their undergraduate degrees. During the mid 1950s, Hoffleit consulted for 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 ...

's Ballistic Research Laboratories in "

Doppler The Doppler effect (also Doppler shift) is the change in the frequency of a wave in relation to an observer who is moving relative to the source of the wave. The ''Doppler effect'' is named after the physicist Christian Doppler, who described ...

reductions". She was the main editor of the Yale ''

Bright Star Catalogue The Bright Star Catalogue, also known as the Yale Catalogue of Bright Stars, Yale Bright Star Catalogue, or just YBS, is a star catalogue that lists all stars of stellar magnitude 6.5 or brighter, which is roughly every star visible to the na ...

.'' The Catalogue is a compendium of information on the 9,110 brightest stars in the sky. She also co-authored ''

The General Catalogue of Trigonometric Stellar Parallaxes A star catalogue is an astronomical catalogue that lists stars. In astronomy, many stars are referred to simply by catalogue numbers. There are a great many different star catalogues which have been produced for different purposes over the year ...

'', containing precise distance measurements to 8,112 stars, information critical to understanding the

kinematics In physics, kinematics studies the geometrical aspects of motion of physical objects independent of forces that set them in motion. Constrained motion such as linked machine parts are also described as kinematics. Kinematics is concerned with s ...

of the

Milky Way galaxy The Milky Way or Milky Way Galaxy is the galaxy that includes the 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 in other arms of the galaxy, which are ...

and the evolution of the

solar neighborhood The Local Interstellar Cloud (LIC), also known as the Local Fluff, is an interstellar cloud roughly across, through which the Solar System is moving. This feature overlaps with a region around the Sun referred to as the solar neighborhood. It i ...

. With Harlan J. Smith, Hoffleit discovered the optical variability of the first-discovered

quasar A quasar ( ) is an extremely Luminosity, luminous active galactic nucleus (AGN). It is sometimes known as a quasi-stellar object, abbreviated QSO. The emission from an AGN is powered by accretion onto a supermassive black hole with a mass rangi ...

3C 273 3C 273 is a quasar located at the center of a giant elliptical galaxy in the constellation of Virgo. It was the first quasar ever to be identified and is the visually brightest quasar in the sky as seen from Earth, with an apparent visual magnitud ...

. In 1988, Hoffleit was awarded the

George Van Biesbroeck Prize The George Van Biesbroeck Prize is an award for long-term achievements in the field of astronomy. According to the American Astronomical Society awards website; "The Van Biesbroeck prize is normally awarded every two years and honors a living indi ...

by the

American Astronomical Society The American Astronomical Society (AAS, sometimes spoken as "double-A-S") is an American society of professional astronomers and other interested individuals, headquartered in Washington, DC. The primary objective of the AAS is to promote the adv ...

for a lifetime of service to astronomy. On March 7-8, 1997,

hosted a symposium in honor of Hoffleit's 90th birthday, dedicated to her nearly 70-year career. Hoffleit turned

100 100 or one hundred (Roman numeral: C) is the natural number following 99 and preceding 101. In mathematics 100 is the square of 10 (in scientific notation it is written as 102). The standard SI prefix for a hundred is " hecto-". 100 is the b ...

on March 12, 2007, and died a month later from complications of cancer.

References

External links

Dr. Dorrit Hoffleit, member of the Connecticut Women's Hall of Fame
*

from the

Astronomical Society of the Pacific The Astronomical Society of the Pacific (ASP) is an American scientific and educational organization, founded in San Francisco on February 7, 1889, immediately following the solar eclipse of January 1, 1889. Its name derives from its origins on ...

Papers, 1906–2005.Schlesinger Library
Radcliffe Institute, Harvard University. * Picture of Dorrit Hoffleit

E. Dorrit Hoffleit Papers (MS 1915).
Manuscripts and Archives, Yale University Library. * Michael Saladyga and Elizabeth Waagen,
In Memoriam: Dorrit Hoffleit
', on ''aavso.org.'' {{DEFAULTSORT:Hoffleit, Dorrit 1907 births 2007 deaths 20th-century American women scientists 20th-century American scientists 21st-century American women People from Florence, Alabama American astronomers American women centenarians American women astronomers Radcliffe College alumni Harvard University faculty Yale University faculty Harvard College Observatory people American women academics

Life

See also

References

Further reading

External links