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Michelson stellar interferometer

astronomical instrument for measuring angular diameter of stars by means of interferometry

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Record originEnglish Wikipedia
Text licenseCC BY-SA 4.0
Source revisionJan 4, 2026
Entity authorityQ915700
Source-derived summary

The Michelson stellar interferometer is one of the earliest astronomical interferometers built and used. The interferometer was proposed by Albert A. Michelson in 1890, following a suggestion by Hippolyte Fizeau.

The first such interferometer built was at the Mount Wilson Observatory, making use of its 100-inch (~250 centimeters) mirror. It was used to make the first-ever measurement of a stellar diameter, by Michelson and Francis G. Pease, when the diameter of Betelgeuse was measured in December 1920. The diameter was found to be 240 million miles (~380 million kilometers), about the size of the orbit of Mars, or about 300 times larger than the Sun.

See also

History of astronomical interferometry

Fizeau interferometer

Michelson interferometer

References

Michelson, A. A., and Pease, F. G. (1921). Astrophys. J. 53, 249–259.

Editorial summary

Begin with the source’s own compact description: “Michelson stellar interferometer” is astronomical instrument for measuring angular diameter of stars by means of interferometry. The dossier treats that line as a proposition to test through Michelson, stellar and interferometer, not as a finished interpretation.

Editorial reviewA concise reference frame for defining the subject, testing terminology and identifying the institution closest to the evidence. The current lead gives the account dated anchors—1890, 1920, 1921—that can be checked directly. The selected authority fields contribute no independent date. For this dossier, Michelson, stellar and interferometer is the immediate research focus.
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Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Jan 4, 2026. The linked authority identifier is Q915700. None of the 0 selected statements returned an explicit reference. The first chronological checks are 1890, 1920 and 1921.

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This entry incorporates text from Michelson stellar interferometer” 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.