About Philip Childs Keenan
Lived 1908 – 2000 (aged 92). Philip Childs Keenan was an American astronomer.
Philip Childs Keenan (March 31, 1908 – April 20, 2000) was an American astronomer.
Keenan was an American spectroscopist who collaborated with William Wilson Morgan and Edith Kellman (1911–2007) to develop the MKK stellar spectral classification system between 1939 and 1943. This two-dimensional classification system (temperature & luminosity) was further revised by Morgan and Keenan in 1973. The MK system remains the standard stellar spectral classification system used by astronomers today.
During their long collaboration, Keenan tended to focus his research on stars cooler than the Sun, while Morgan emphasized the hotter stars. Keenan had a long and productive career, publishing his final scientific paper in 1999, seventy years after his first.
Honors Named after him Asteroid 10030 Philkeenan
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Frequently asked questions
Who was Philip Childs Keenan?
American astronomer (1908–2000)
When was Philip Childs Keenan born?
Philip Childs Keenan was born on 31 March 1908 in Bellevue.
When did Philip Childs Keenan die?
Philip Childs Keenan died on 20 April 2000 in Columbus.
What was Philip Childs Keenan's occupation?
Philip Childs Keenan was an astronomer.
What nationality was Philip Childs Keenan?
Philip Childs Keenan was American.
Sources & further reading
· Wikipedia: Philip Childs Keenan
· DBpedia: Philip Childs Keenan
Cite this page
APA: Biography.guide. (2026). Philip Childs Keenan. https://biography.guide/philip-childs-keenan/
MLA: "Philip Childs Keenan." Biography.guide, https://biography.guide/philip-childs-keenan/.
Chicago: "Philip Childs Keenan." Biography.guide. https://biography.guide/philip-childs-keenan/.
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