Harold Alden
Encyclopedia
Harold Lee Alden was an American
astronomer
. He was born in Chicago, Illinois.
He received a BA from Wheaton College
in 1912, and went on to receive his Master's degree from the University of Chicago
in 1913. He served as an assistant in photographic
photometry
program of the Yerkes Observatory
1912-1914. He studied at the University of Virginia
under Samuel Alfred Mitchell
, receiving his Ph.D. in 1917 (title: Observations of long period variable stars at the Leander McCormick Observatory). He became an associate professor at Virginia in 1924, but left the following year to become the director of Yale University's
newly established (by Frank Schlesinger
) southern station in Johannesburg, South Africa. Alden spent twenty years at the Yale Observatory working on the long-focus refractor to determine parallax
es of southern stars. He also concerned himself with a study of the probable error
s in the parallax plates taken in Johannesburg.
Alden returned to the University of Virginia in 1945 to succeed Samuel Alfred Mitchell as Professor of Astronomy, chairman of the Astronomy Department and Director of the Leander McCormick Observatory
. The majority of Alden's work at Virginia, both before and after his term at the Yale Observatory, consisted of measurements of stellar parallaxes, proper motions and visual observations of long-period variable stars. He was best remembered for his published studies in long-focus photographic astrometry from both McCormick and Yale Observatories. He was vice-president of the American Association for the Advancement of Science
and chairman of its section D (astronomy) in 1951. From 1952 to 1955, he served as the president of Commission 24, the Stellar Parallaxes section, of the International Astronomical Union
.
Alden retired from his position at the University of Virginia on June 30, 1960. He died in Charlottesville on February 3, 1964, survived by his wife Mildred, three children and eleven grandchildren. The crater Alden
on the far side of the Moon
is named in his honor.
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
astronomer
Astronomer
An astronomer is a scientist who studies celestial bodies such as planets, stars and galaxies.Historically, astronomy was more concerned with the classification and description of phenomena in the sky, while astrophysics attempted to explain these phenomena and the differences between them using...
. He was born in Chicago, Illinois.
He received a BA from Wheaton College
Wheaton College (Illinois)
Wheaton College is a private, evangelical Protestant liberal arts college in Wheaton, Illinois, a suburb west of Chicago in the United States...
in 1912, and went on to receive his Master's degree from the University of Chicago
University of Chicago
The University of Chicago is a private research university in Chicago, Illinois, USA. It was founded by the American Baptist Education Society with a donation from oil magnate and philanthropist John D. Rockefeller and incorporated in 1890...
in 1913. He served as an assistant in photographic
Photography
Photography is the art, science and practice of creating durable images by recording light or other electromagnetic radiation, either electronically by means of an image sensor or chemically by means of a light-sensitive material such as photographic film...
photometry
Photometry (astronomy)
Photometry is a technique of astronomy concerned with measuring the flux, or intensity of an astronomical object's electromagnetic radiation...
program of the Yerkes Observatory
Yerkes Observatory
Yerkes Observatory is an astronomical observatory operated by the University of Chicago in Williams Bay, Wisconsin. The observatory, which calls itself "the birthplace of modern astrophysics," was founded in 1897 by George Ellery Hale and financed by Charles T. Yerkes...
1912-1914. He studied at the University of Virginia
University of Virginia
The University of Virginia is a public research university located in Charlottesville, Virginia, United States, founded by Thomas Jefferson...
under Samuel Alfred Mitchell
Samuel Alfred Mitchell
Samuel Alfred Mitchell was an astronomer who studied solar eclipses and set up a program to use photographic techniques to determine the distance to stars at McCormick Observatory, where he served as the director.-Early years:Mitchell was the son of John Cook and Sarah Chown Mitchell,...
, receiving his Ph.D. in 1917 (title: Observations of long period variable stars at the Leander McCormick Observatory). He became an associate professor at Virginia in 1924, but left the following year to become the director of Yale University's
Yale University
Yale University is a private, Ivy League university located in New Haven, Connecticut, United States. Founded in 1701 in the Colony of Connecticut, the university is the third-oldest institution of higher education in the United States...
newly established (by Frank Schlesinger
Frank Schlesinger
Frank Schlesinger was an American astronomer. His work concentrated on using photographic plates rather than direct visual studies for astronomical research.-Biography:...
) southern station in Johannesburg, South Africa. Alden spent twenty years at the Yale Observatory working on the long-focus refractor to determine parallax
Parallax
Parallax is a displacement or difference in the apparent position of an object viewed along two different lines of sight, and is measured by the angle or semi-angle of inclination between those two lines. The term is derived from the Greek παράλλαξις , meaning "alteration"...
es of southern stars. He also concerned himself with a study of the probable error
Probable error
-Statistics:In statistics, the probable error of a quantity is a value describing the probability distribution of that quantity. It defines the half-range of an interval about a cental point for the distribution, such that half of the values from the distribution will lie within the interval and...
s in the parallax plates taken in Johannesburg.
Alden returned to the University of Virginia in 1945 to succeed Samuel Alfred Mitchell as Professor of Astronomy, chairman of the Astronomy Department and Director of the Leander McCormick Observatory
McCormick Observatory
The McCormick Observatory is one of the astronomical observatories operated by the Department of Astronomy of the University of Virginia and is situated just outside of Charlottesville, Virginia in Albemarle County on the summit of Mount Jefferson . It is named for Leander J...
. The majority of Alden's work at Virginia, both before and after his term at the Yale Observatory, consisted of measurements of stellar parallaxes, proper motions and visual observations of long-period variable stars. He was best remembered for his published studies in long-focus photographic astrometry from both McCormick and Yale Observatories. He was vice-president of the American Association for the Advancement of Science
American Association for the Advancement of Science
The American Association for the Advancement of Science is an international non-profit organization with the stated goals of promoting cooperation among scientists, defending scientific freedom, encouraging scientific responsibility, and supporting scientific education and science outreach for the...
and chairman of its section D (astronomy) in 1951. From 1952 to 1955, he served as the president of Commission 24, the Stellar Parallaxes section, of the International Astronomical Union
International Astronomical Union
The International Astronomical Union IAU is a collection of professional astronomers, at the Ph.D. level and beyond, active in professional research and education in astronomy...
.
Alden retired from his position at the University of Virginia on June 30, 1960. He died in Charlottesville on February 3, 1964, survived by his wife Mildred, three children and eleven grandchildren. The crater Alden
Alden (crater)
Alden is a lunar crater that lies on the far side of the Moon, between Hilbert to the north-northwest and Milne to the south-southeast. To the south-southwest lies Scaliger....
on the far side of the Moon
Moon
The Moon is Earth's only known natural satellite,There are a number of near-Earth asteroids including 3753 Cruithne that are co-orbital with Earth: their orbits bring them close to Earth for periods of time but then alter in the long term . These are quasi-satellites and not true moons. For more...
is named in his honor.