Born December 29, 1852 Strzelno, Poland
Died May 9, 1931 Pasadena, California
prizes Nobel Prize for Physics (1907)
Albert Abraham Michelson (surname pronunciation anglicised as "Michael-son")
(December 19, 1852 – May 9, 1931) was a Polish-born German-American
physicist known for his work on the measurement of the speed of light
and especially for the Michelson-Morley experiment. In 1907 he received
the Nobel Prize in Physics, the first American to receive the Nobel
in the sciences.
Michelson, the son of a Jewish merchant, was born in, what is today
Strzelno, Poland (then Strelno, Provinz Posen in the Prussian-occupied
region of partitioned Poland). He moved to the United States with his
parents in 1855, when he was two years old. He grew up in the rough
mining towns of Murphy's Camp, California and Virginia City, Nevada,
where his father was a merchant.
S. Grant awarded Michelson a special appointment to the U.S. Naval Academy
in 1869. During his four years as a midshipman at the Academy, Michelson
excelled in optics, heat and climatology as well as drawing. After his
graduation in 1873 and two years at sea, he returned to the Academy
in 1875 to become an instructor in physics and chemistry until 1879.
From 1880 to 1882, Michelson undertook postgraduate study at Berlin
under Hermann Helmholtz and at Paris.
for the paper pictured above.Michelson was fascinated with the sciences
and the problem of measuring the speed of light in particular. While
at Annapolis, he conducted his first experiments of the speed of light,
as part of a class demonstration in 1877. After two years of studies
in Europe, he resigned from the Navy in 1881. In 1883 he accepted a
position as professor of physics at the Case School of Applied Science
in Cleveland, Ohio and concentrated on developing an improved interferometer.
In 1887 he and Edward Morley carried out the famous Michelson-Morley
experiment which seemed to rule out the existence of the aether. He
later moved on to use astronomical interferometers in the measurement
of stellar diameters and in measuring the separations of binary stars.
In 1889 Michelson
became a professor at Clark University at Worcester, Massachusetts and
in 1892 was appointed professor and the first head of the department
of physics at the newly organized University of Chicago.
In 1899, he married
Edna Stanton and they raised one son and three daughters.
In 1907, Michelson
had the honor of being the first American to receive a Nobel Prize in
Physics "for his optical precision instruments and the spectroscopic
and metrological investigations carried out with their aid". He
also won the Copley Medal in 1907, the Henry Draper Medal in 1916 and
the Gold Medal of the Royal Astronomical Society in 1923. A crater on
the Moon is named after him.
Michelson died in
Pasadena, California at the age of 78. The University of Chicago Residence
Halls remembered Michelson and his achievements by dedicating Michelson
House in his honor. Case Western Reserve has also dedicated a Michelson
House to him, and an academic building at the United States Naval Academy
also bears his name. Michelson Laboratory at China Lake Naval Weapons
Center in Ridgecrest, California is named after him. There is an interesting
display in the publicly accessible area of the Lab of Michelson's Nobel
Prize medal, the actual prize document, and examples of his diffraction
Speed of light
As early as 1877, while still serving as an officer in the US Navy,
Michelson started planning a refinement of the rotating-mirror method
of Léon Foucault for measuring the speed of light, using improved
optics and a longer baseline. He conducted some preliminary measurements
using largely improvised equipment in 1878 about which time his work
came to the attention of Simon Newcomb, director of the Nautical Almanac
Office who was already advanced in planning his own study. Michelson
published his result of 299,910±50 km/s in 1879 before joining
Newcomb in Washington DC to assist with his measurements there. Thus
began a long professional collaboration and friendship between the two.
Newcomb, with his
more adequately funded project, obtained a value of 299,860±30
km/s, just at the extreme edge of consistency with Michelson's. Michelson
continued to "refine" his method and in 1883 published a measurement
of 299,853±60 km/s, rather closer to that of his mentor.
In 1906, a novel
electrical method was used by E. B. Rosa and N. E. Dorsey of the National
Bureau of Standards to obtain a value for the speed of light of 299,781±10
km/s. Though this result has subsequently been shown to be severely
biased by the poor electrical standards in use at the time, it seems
to have set a fashion for rather lower measured values.
From 1920, Michelson
started planning a definitive measurement from the Mount Wilson Observatory,
using a baseline to Lookout Mountain, a prominent bump on the south
ridge of Mount San Antonio (Old Baldy), some 22 miles distant.
In 1922, the U.S.
Coast and Geodetic Survey began two years of painstaking measurement
of the baseline using the recently available invar tapes. With the baseline
length established in 1924, measurements were carried out over the next
two years to obtain the published value of 299,796±4 km/s.
Famous as the measurement
is, it was beset by problems, not least of which was the haze created
by the smoke from forest fires which blurred the mirror image. It is
also probable that the intensively detailed work of the Geodetic Survey,
with an estimated error of less than one part in 1 million, was compromised
by a shift in the baseline arising from the Santa Barbara earthquake
of 29 June 1925 which was an estimated magnitude of 6.3 on the Richter
& Pearson 1932
The period after 1927 marked the advent of new measurements of the speed
of light using novel electro-optic devices, all substantially lower
than Michelson's 1926 value.
another measurement but this time in an evacuated tube to avoid difficulties
in interpreting the image owing to atmospheric effects. In 1930, he
began a collaboration with Francis G. Pease and Fred Pearson to perform
a measurement in a 1.6 km tube at Pasadena, California. Michelson died
with only 36 of the 233 measurement series completed and the experiment
was subsequently beset by geological instability and condensation problems
before the result of 299,774±11 km/s, consistent with the prevailing
electro-optic values, was published posthumously in 1935.
In 1887 he collaborated with colleague Edward Williams Morley in the
Michelson-Morley experiment. Their experiment for the expected motion
of the Earth relative to the aether, the hypothetical medium in which
light was supposed to travel, resulted in a null result. Though it may
appear that Albert Einstein did not know of the work (according to his
1905 paper), it greatly assisted the acceptance of the theory of relativity...
In 1920-21 Michelson and Francis G. Pease famously became the first
people to measure the diameter of a star other than our Sun. They used
an astronomical interferometer at the Mount Wilson Observatory to measure
the diameter of the super-giant star Betelgeuse. A periscope arrangement
was used to obtain a densified pupil in the interferometer, a method
later investigated in detail by Labeyrie for use in with "Hypertelescopes".
The measurement of stellar diameters and the separations of binary stars
took up an increasing amount of Michelson's life after this.
Albert Abraham Michelson was born in Strelno, Prussia, on December 19,
1852. Two years later his family emigrated to the United States to settle
at Virginia City, Nevada, but they eventually moved to San Francisco
where Michelson received his early education in public schools, matriculating
from the High School in 1869. He was appointed by President Grant to
the U.S. Naval Academy and, after graduation as Ensign in 1873 and a
two-years' cruise in the West Indies, he became an instructor in physics
and chemistry at the Academy under Admiral Sampson. In 1879, he was
posted to the Nautical Almanac Office, Washington, to work with Simon
Newcomb, but in the following year, he obtained leave of absence to
continue his studies in Europe. He visited the Universities of Berlin
and Heidelberg, and the College de France and École Polytechnique
in Paris. He resigned from the Navy and in 1883 returned to America
to take an appointment as Professor of Physics in the Case School of
Applied Science, Cleveland, Ohio. In 1890 he accepted a similar position
at Clark University, Worcester, Massachusetts, and in 1892 he became
Professor of Physics and the first Head of Department at the new University
of Chicago. He rejoined the Navy during World War I, and in 1918 returned
to Chicago where in 1925 he was appointed to the first of the Distinguished
Service Professorships. Michelson resigned in 1929 to work at the Mount
Wilson Observatory, Pasadena.
During his career,
Michelson touched on many departments of physics but, perhaps due to
a special instinct which he appeared to possess, he excelled in optics.
He performed early measurements of the velocity of light with amazing
delicacy and in 1881 he invented his interferometer for the purpose
of discovering the effect of the Earth's motion on the observed velocity.
In cooperation with Professor E.W. Morley, and using the interferometer,
it was shown that light travels at a constant speed in all inertial
systems of reference. The instrument also enabled distances to be measured
with greater accuracy by means of the length of light-waves. At the
request of the International Committee of Weights and Measures, Michelson
measured the standard metre in terms of wavelength of cadmium light.
He invented the echelon spectroscope and during his wartime service
in the Navy he performed research work on devices for naval use - he
developed a rangefinder which was adapted as part of U.S. Navy equipment.
On his return to civilian life, Michelson became more interested in
astronomy and in 1920, using light interference and a highly developed
version of his earlier instrument, he measured the diameter of the star
Betelgeuse: this was the first determination of the size of a star that
could be regarded as accurate.
Michelson has contributed
numerous papers to many scientific periodicals and among his more substantial
works are the classics, Velocity of Light (1902) Light Waves and their
Uses (1899-1903); and Studies in Optics (1927).
Michelson was honoured
by memberships of many learned societies throughout America and ten
European countries, and he received honorary science and law degrees
from ten American and foreign universities. He was President of the
American Physical Society (1900), the American Association for the Advancement
of Science (1910-1911), and the National Academy of Sciences (1923-1927).
He was also a Fellow of the Royal Astronomical Society, the Royal Society
of London and the Optical Society, an Associate of l'Académie
Française and among the many awards he has received are the Matteucci
Medal (Societá Italiana), 1904; Copley Medal (Royal Society),
1907; Elliot Cresson Medal (Franklin Institute), 1912; Draper Medal
(National Academy of Sciences), 1916; Franklin Medal (Franklin Institute)
and the Medal of the Royal Astronomical Society, 1923; and the Duddell
Medal (Physical Society), 1929.
Edna Stanton of Lake Forest, Illinois in 1899. They had one son and
three daughters. He died in 1931.
Albert A. Michelson
died on May 9, 1931.