John A. Eddy

John Allen Eddy
John Allen Eddy
	Gordon Newkirk

John Allen "Jack" Eddy (March 25, 1931 – June 10, 2009) was an American astronomer. He studied historical sunspot records, and popularised the name Maunder Minimum for the sunspot minimum which occurred in the late 17th century.

Childhood and education

Annapolis, there were few science courses but Eddy attended a course in celestial navigation, which gave him a love of the sky. So great was his interest in the night sky that once after Taps, he crawled out on the roof of Bancroft Hall to look for the Constellation Draco and was caught by an officer who gave him five hours of extra duty for not being in bed.^{[citation needed}

]

Upon graduation in 1953 from the

University of Colorado.^[3]^[4]

Academic career

As a protege of

University of Colorado at Boulder in December 1961 titled "The Stratospheric Solar Aureole".^[5] After obtaining his PhD, Eddy went into teaching, while maintaining an active research schedule to maintain his credentials. He studied spectral lines and worked on infrared spectroscopy.^[3]

Interdisciplinary work

Eddy received much criticism from within the astronomy community for his interdisciplinary work on

National Geographic

and as a guest on TV and radio programs.

As a teacher, he frequently used historical examples to show his students that not so long ago nobody knew more than they did about solar physics. This led him to do a lot of research in the history of his own field, particularly covering records of past eclipses and sunspot counts, whereupon he discovered the records of

Edward Maunder and others demonstrating that there was indeed long term variability in solar activity. Eugene Parker of the University of Chicago, when promoting his theory of the existence of a solar wind, exposed Eddy to Maunder's work on sunspot records.^[3]

Solar minimum paper

In 1976 Eddy published a paper in

tree-rings. In the last of these, which can be used as a proxy indicator of solar activity, he found evidence of other similar periods of solar quiescence in the distant past, the most recent an even longer 90-year span, from about 1460 until 1550, which he named the Spörer Minimum

.

Both the Maunder and Spörer minima fell during the coldest parts of the

sunspot numbers is taken as evidence of the second. Both records, however, sample only the most recent history of the Sun."^[7]

Post-academia

Eddy was laid off from the High Altitude Observatory at the

Naval Observatory, which he used to also do research on the Maunder Minimum.^[3] His work on this was published in the journal Science as a cover story.^[7] After publication, his former employers at the HAO tried to hire him back.^{[citation needed]} The interest resulting from "The Maunder Minimum" paper saw him giving over 50 talks a year around the world about his work and history.^{[citation needed}

]

In 1987 Eddy was awarded the

National Academy of Sciences

for studies in solar physics and solar-terrestrial relationships and specifically for "his demonstration of the existence and nature of solar variations of long term and the consequences of these changes for climate and for mankind."