Eugene Newman Parker (June 10, 1927 – March 15, 2022) was an American solar and plasma physicist. In the 1950s he proposed the existence of the

solar wind The solar wind is a stream of charged particles released from the upper atmosphere of the Sun, called the corona. This plasma mostly consists of electrons, protons and alpha particles with kinetic energy between . The composition of the sol ...

and that the magnetic field in the outer Solar System would be in the shape of a Parker spiral, predictions that were later confirmed by spacecraft measurements. In 1987, Parker proposed the existence of nanoflares, a leading candidate to explain the

coronal heating problem A corona ( coronas or coronae) is the outermost layer of a star's atmosphere. It consists of plasma. The Sun's corona lies above the chromosphere and extends millions of kilometres into outer space. It is most easily seen during a total solar ...

. Parker obtained his PhD from

Caltech 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 ...

and spent four years as a

postdoctoral researcher A postdoctoral fellow, postdoctoral researcher, or simply postdoc, is a person professionally conducting research after the completion of their doctoral studies (typically a PhD). The ultimate goal of a postdoctoral research position is to pu ...

at the

University of Utah The University of Utah (U of U, UofU, or simply The U) is a public research university in Salt Lake City, Utah. It is the flagship institution of the Utah System of Higher Education. The university was established in 1850 as the University of De ...

. He joined

University of Chicago The University of Chicago (UChicago, Chicago, U of C, or UChi) is a private research university in Chicago, Illinois. Its main campus is located in Chicago's Hyde Park neighborhood. The University of Chicago is consistently ranked among the b ...

in 1955 and spent the rest of his career there, holding positions in the physics department, the

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 ...

and

astrophysics Astrophysics is a science that employs the methods and principles of physics and chemistry in the study of astronomical objects and phenomena. As one of the founders of the discipline said, Astrophysics "seeks to ascertain the nature of the h ...

department, and the Enrico Fermi Institute. Parker was elected to the

National Academy of Sciences The National Academy of Sciences (NAS) is a United States nonprofit, non-governmental organization. NAS is part of the National Academies of Sciences, Engineering, and Medicine, along with the National Academy of Engineering (NAE) and the Nat ...

in 1967. In 2017,

NASA The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeedin ...

named its

Parker Solar Probe The Parker Solar Probe (PSP; previously Solar Probe, Solar Probe Plus or Solar Probe+) is a NASA space probe launched in 2018 with the mission of making observations of the outer corona of the Sun. It will approach to within 9.86 solar radii ...

in his honor, the first NASA spacecraft named after a living person.

Biography

Parker was born in

Houghton, Michigan Houghton (; ) is the largest city and seat of government of Houghton County in the U.S. state of Michigan. Located on the Keweenaw Peninsula, Houghton is the largest city in the Copper Country region. It is the fifth-largest city in the U ...

to Glenn and Helen (MacNair) Parker on June 10, 1927. He received his

Bachelor of Science A Bachelor of Science (BS, BSc, SB, or ScB; from the Latin ') is a bachelor's degree awarded for programs that generally last three to five years. The first university to admit a student to the degree of Bachelor of Science was the University o ...

degree in

physics Physics is the natural science that studies matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge which ...

from

Michigan State University Michigan State University (Michigan State, MSU) is a public land-grant research university in East Lansing, Michigan. It was founded in 1855 as the Agricultural College of the State of Michigan, the first of its kind in the United States. It ...

in 1948 and a

Doctor of Philosophy A Doctor of Philosophy (PhD, Ph.D., or DPhil; Latin: or ') is the most common degree at the highest academic level awarded following a course of study. PhDs are awarded for programs across the whole breadth of academic fields. Because it is ...

from Caltech in 1951. Parker spent four years at the

before joining the University of Chicago in 1955, where he spent the rest of his career. He held positions in Chicago's physics department,

and

department, and the Enrico Fermi Institute. Parker was elected to the

in 1967.

Hypotheses

In the mid-1950s, Parker developed the theory of the supersonic

and predicted the Parker spiral shape of the solar magnetic field in the outer Solar System. His theoretical modeling was not immediately accepted by the astronomical community: when he submitted the results to ''

The Astrophysical Journal ''The Astrophysical Journal'', often abbreviated ''ApJ'' (pronounced "ap jay") in references and speech, is a peer-reviewed scientific journal of astrophysics and astronomy, established in 1895 by American astronomers George Ellery Hale and J ...

'', two reviewers recommended its rejection. The editor of the journal,

Subrahmanyan Chandrasekhar Subrahmanyan Chandrasekhar (; ) (19 October 1910 – 21 August 1995) was an Indian-American theoretical physicist who spent his professional life in the United States. He shared the 1983 Nobel Prize for Physics with William A. Fowler for " ...

, overruled the reviewers and published the paper anyway. Parker's theoretical predictions were confirmed by satellite observations a few years later, especially the 1962 Mariner 2 mission. Parker's work increased understanding of the solar corona, the

, the

magnetic field A magnetic field is a vector field that describes the magnetic influence on moving electric charges, electric currents, and magnetic materials. A moving charge in a magnetic field experiences a force perpendicular to its own velocity and to ...

s of both the Earth and the Sun, and their complex electromagnetic interactions. He published several

textbook A textbook is a book containing a comprehensive compilation of content in a branch of study with the intention of explaining it. Textbooks are produced to meet the needs of educators, usually at educational institutions. Schoolbooks are textbook ...

s, including ''Cosmical Magnetic Fields'' in 1979, and one on magnetic fields in X-ray astronomy in 1994. Seeking to address the

, in 1987 Parker proposed that the solar corona might be heated by myriad tiny " nanoflares", miniature brightenings resembling

solar flare A solar flare is an intense localized eruption of electromagnetic radiation in the Sun's atmosphere. Flares occur in active regions and are often, but not always, accompanied by coronal mass ejections, solar particle events, and other sol ...

s that would occur all over the surface of the Sun. Parker's theory became a leading candidate to explain the problem.

Personal life

Parker was married to his wife, Niesje, for 67 years, with whom he had two children. He died in Chicago on March 15, 2022, at the age of 94.

Honors and awards

* 1969:

Arctowski Medal The Arctowski Medal is awarded by the U.S. National Academy of Sciences "for studies in solar physics and solar-terrestrial relationships." Named in honor of Henryk Arctowski, it was first awarded in 1969. List of Arctowski Medal winners SourceN ...

of the

* 1969: Henry Norris Russell Lectureship of 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 ...

* 1978: George Ellery Hale Prize, Solar Physics Division of the American Astronomical Society, first time this prize was awarded *1979:

Chapman Medal The Chapman Medal is an award of the Royal Astronomical Society, given for "investigations of outstanding merit in the science of the Sun, space and planetary environments or solar-terrestrial physics". It is named after Sydney Chapman (1888� ...

, Royal Astronomical Society * 1989:

National Medal of Science The National Medal of Science is an honor bestowed by the President of the United States to individuals in science and engineering who have made important contributions to the advancement of knowledge in the fields of behavioral and social scienc ...

* 1990:

William Bowie Medal The William Bowie Medal is awarded annually by the American Geophysical Union for "outstanding contributions to fundamental geophysics and for unselfish cooperation in research". The award is the highest honor given by the AGU and is named in honor ...

* 1992:

Gold Medal of the Royal Astronomical Society The Gold Medal of the Royal Astronomical Society is the highest award given by the Royal Astronomical Society (RAS). The RAS Council have "complete freedom as to the grounds on which it is awarded" and it can be awarded for any reason. Past awar ...

* 1997:

Bruce Medal The Catherine Wolfe Bruce Gold Medal is awarded every year by the Astronomical Society of the Pacific for outstanding lifetime contributions to astronomy. It is named after Catherine Wolfe Bruce, an American patroness of astronomy, and was fi ...

* 2003: Kyoto Prize * 2003: James Clerk Maxwell Prize of the

American Physical Society The American Physical Society (APS) is a not-for-profit membership organization of professionals in physics and related disciplines, comprising nearly fifty divisions, sections, and other units. Its mission is the advancement and diffusion of k ...

. Citation: "For seminal contributions in plasma astrophysics, including predicting the

, explaining the solar dynamo, formulating the theory of magnetic reconnection, and the

instability In numerous fields of study, the component of instability within a system is generally characterized by some of the outputs or internal states growing without bounds. Not all systems that are not stable are unstable; systems can also be mar ...

which predicts the escape of the

s from the galaxy." * 2010: Member of the

Norwegian Academy of Science and Letters The Norwegian Academy of Science and Letters ( no, Det Norske Videnskaps-Akademi, DNVA) is a learned society based in Oslo, Norway. Its purpose is to support the advancement of science and scholarship in Norway. History The Royal Frederick Unive ...

. * 2017:

renamed its ''Solar Probe Plus'' to ''

'' after Parker, the first time that a space vessel was named after a living person. Parker was present at its August 12, 2018, launch. * 2018: Medal for Exceptional Achievement in Research of the

. Citation: "For fundamental contributions to space physics, plasma physics, solar physics and astrophysics for over 60 years." * 2020: Crafoord Prize in Astronomy

Books

* ''Cosmical Magnetic Fields: Their Origin and their Activity'', 1979, Oxford University Press. . * ''Spontaneous Current Sheets in Magnetic Fields: With Applications to Stellar X-rays'', 1994, Oxford University Press. . * ''Conversations on Electric and Magnetic Fields in the Cosmos'', 2007, Princeton University Press. .

References

{{DEFAULTSORT:Parker, Eugene 1927 births 2022 deaths 20th-century American astronomers 21st-century American astronomers American astrophysicists American plasma physicists Fellows of the American Physical Society Fellows of the Royal Astronomical Society Foreign Fellows of the Royal Astronomical Society Kyoto laureates in Basic Sciences Members of the Norwegian Academy of Science and Letters Members of the United States National Academy of Sciences Michigan State University alumni National Medal of Science laureates People from Houghton, Michigan Recipients of the Gold Medal of the Royal Astronomical Society Scientists from Michigan University of Chicago faculty University of Utah faculty Writers from Michigan