Mark Inghram
Encyclopedia
Mark G. Inghram was an American
physicist
.
, Montana
. He did undergraduate work at Olivet College
, receiving a B.A.
in 1939. He worked in the Manhattan Project
during World War II
and at Argonne National Laboratories from 1945 to 1947. He received his Ph.D.
from the University of Chicago
in 1947. He began teaching at the University of Chicago
as an instructor in 1947 and remained there until his retirement in 1985. He died at his home in Holland
, Michigan
in 2003.
Together with Clair Patterson and George Tilton, Inghram was one of the first scientists to combine measurements on meteorites and the Earth
to find the age of the Earth
. Over time, the decay of uranium
to lead
will change the isotopic makeup of terrestrial lead. Patterson, Tilton and Inghram assumed that iron meteorites, which contain lead but virtually no uranium, formed at the same time as the Earth. Assuming this to be true, the isotopic makeup of lead in iron meteorites should still be the same as that of the newly formed Earth, so the Earth can be dated by comparing the composition of lead in iron meteorites with that in new volcanic material on the Earth. Patterson, Tilton and Inghram did this and found that the Earth was approximately 4.5 billion years old.
Inghram was a member of the National Academy of Sciences
.
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
physicist
Physicist
A physicist is a scientist who studies or practices physics. Physicists study a wide range of physical phenomena in many branches of physics spanning all length scales: from sub-atomic particles of which all ordinary matter is made to the behavior of the material Universe as a whole...
.
Life
Inghram was born in LivingstonLivingston, Montana
-Geography:Livingston is located at , at an altitude of 4.501 feet .According to the United States Census Bureau, the city has a total area of , of which, of it is land and 0.38% is waters.-Climate:-Demographics:...
, Montana
Montana
Montana is a state in the Western United States. The western third of Montana contains numerous mountain ranges. Smaller, "island ranges" are found in the central third of the state, for a total of 77 named ranges of the Rocky Mountains. This geographical fact is reflected in the state's name,...
. He did undergraduate work at Olivet College
Olivet College
Olivet College is a coeducational, liberal arts college located in Olivet, Michigan, United States, south of Lansing and west of Detroit. It is affiliated with the United Church of Christ and the National Association of Congregational Christian Churches, and accredited by the North Central...
, receiving a B.A.
Bachelor of Arts
A Bachelor of Arts , from the Latin artium baccalaureus, is a bachelor's degree awarded for an undergraduate course or program in either the liberal arts, the sciences, or both...
in 1939. He worked in the Manhattan Project
Manhattan Project
The Manhattan Project was a research and development program, led by the United States with participation from the United Kingdom and Canada, that produced the first atomic bomb during World War II. From 1942 to 1946, the project was under the direction of Major General Leslie Groves of the US Army...
during World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
and at Argonne National Laboratories from 1945 to 1947. He received his Ph.D.
Ph.D.
A Ph.D. is a Doctor of Philosophy, an academic degree.Ph.D. may also refer to:* Ph.D. , a 1980s British group*Piled Higher and Deeper, a web comic strip*PhD: Phantasy Degree, a Korean comic series* PhD Docbook renderer, an XML renderer...
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 1947. He began teaching at 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...
as an instructor in 1947 and remained there until his retirement in 1985. He died at his home in Holland
Holland, Michigan
Holland is a city in the western region of the Lower Peninsula of the U.S. state of Michigan. It is situated near the eastern shore of Lake Michigan on Lake Macatawa, which is fed by the Macatawa River ....
, Michigan
Michigan
Michigan is a U.S. state located in the Great Lakes Region of the United States of America. The name Michigan is the French form of the Ojibwa word mishigamaa, meaning "large water" or "large lake"....
in 2003.
Together with Clair Patterson and George Tilton, Inghram was one of the first scientists to combine measurements on meteorites and the Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...
to find the age of the Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...
. Over time, the decay of uranium
Uranium
Uranium is a silvery-white metallic chemical element in the actinide series of the periodic table, with atomic number 92. It is assigned the chemical symbol U. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons...
to lead
Lead
Lead is a main-group element in the carbon group with the symbol Pb and atomic number 82. Lead is a soft, malleable poor metal. It is also counted as one of the heavy metals. Metallic lead has a bluish-white color after being freshly cut, but it soon tarnishes to a dull grayish color when exposed...
will change the isotopic makeup of terrestrial lead. Patterson, Tilton and Inghram assumed that iron meteorites, which contain lead but virtually no uranium, formed at the same time as the Earth. Assuming this to be true, the isotopic makeup of lead in iron meteorites should still be the same as that of the newly formed Earth, so the Earth can be dated by comparing the composition of lead in iron meteorites with that in new volcanic material on the Earth. Patterson, Tilton and Inghram did this and found that the Earth was approximately 4.5 billion years old.
Inghram was a member of the National Academy of Sciences
United States National Academy of Sciences
The National Academy of Sciences is a corporation in the United States whose members serve pro bono as "advisers to the nation on science, engineering, and medicine." As a national academy, new members of the organization are elected annually by current members, based on their distinguished and...
.