Gregory Jaczko
chairman of the U.S. Nuclear Regulatory Commission since 2009
Gregory B. Jaczko (; born October 29, 1970, Norristown, Pennsylvania) is a physicist who is the 13th and former chairman of the U.S. Nuclear Regulatory Commission (NRC) from 2009 to 2012. While at the NRC, he voted against the opening of new nuclear plants; an inspector general report found that he sought unilaterally and improperly to block the Yucca Mountain nuclear waste repository project from advancing. After leaving the NRC, Jaczko called for a global ban on nuclear power.
Early life and education
Jaczko was raised in Albany, New York, the son of Kathryn Marie and Bela L. Jaczko. He studied physics and philosophy at Cornell University in Ithaca, New York; he earned a bachelor in the two disciplines there in 1993. In 1999, he earned a doctorate in theoretical particle physics from the University of Wisconsin–Madison.
He is married to journalist Leigh Ann Caldwell.
Political career
Jaczko served as a Congressional Science Fellow in the office of U.S. Representative Ed Markey in Washington, D.C., on the basis of an AAAS Science and Technology Policy Fellowship. He also worked as an adjunct professor for Physics and Public Policy under Dr. Francis Slakey at Georgetown University in Washington, D.C.
He later advised the United States Senate Committee on Environment and Public Works on issues regarding nuclear power.
“Gregory Jaczko” enters the record as chairman of the U.S. Nuclear Regulatory Commission since 2009. Crown Archives preserves that source wording while asking what Gregory, Jaczko and chairman can confirm, complicate or overturn.
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The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Aug 17, 2026. The linked authority identifier is Q513885. VIAF identifies the subject as 41609292. The Library of Congress control number is no2007007920. 3 of 3 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1970, 2009, 2012 and 1993.
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This entry incorporates text from “Gregory Jaczko” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.