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KOI-81

Eclipsing binary system

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General referenceInterpretive dossier study · Crown Archives visual atlas
Record originEnglish Wikipedia
Text licenseCC BY-SA 4.0
Source revisionMay 12, 2025
Entity authorityQ5098516 ↗
Source-derived summary

KOI-81 is an eclipsing binary star in the constellation of Cygnus. The primary star is a late B-type or early A-type main-sequence star with a temperature of 10,000 K (9,700 °C; 17,500 °F). It lies in the field of view of the Kepler Mission and was determined to have an object in orbit around it which is smaller and hotter than the main star.

KOI-81b

KOI-81b is a hot compact object orbiting KOI-81. It was discovered in 2010 by the Kepler Mission and came to attention because of its small size and high temperature of 17,000 K (16,700 °C; 30,100 °F). The orbit of KOI-81b around the main star takes 23.8776 days to complete. Analysis of relativistic effects in the Kepler light curve suggests that it is a low-mass white dwarf of approximately 0.3 solar masses, or the immediate progenitor of such a white dwarf, a hot subdwarf. This small hot star was produced by mass transfer when the primary stripped the outer layers when the secondary expanded after leaving the main sequence.

See also

KOI-74, a similar system also discovered by the Kepler Mission.

Editorial summary

This brief starts where responsible research should: with the source description of “KOI-81” as eclipsing binary system. Everything that follows is an evidence route, not borrowed authority.

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—2010—that can be checked directly. The selected authority fields contribute no independent date. The account is most persuasive where KOI-81, Eclipsing and binary can be independently traced.
Editorial analysis

Why this record matters

The subject matters to the general reference register because the source frames it as eclipsing binary system. Its deeper value depends on whether names, dates, institutions and citations support that framing.

Evidence profile

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 May 12, 2025. The linked authority identifier is Q5098516. None of the 0 selected statements returned an explicit reference. The first chronological checks are 2010.

Critical limits

Overview language is designed for orientation and should not be treated as a substitute for the evidence cited beneath it. The source lead contains qualifying language; that uncertainty should survive quotation, summary and reuse. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.

How to read it

Use the entry as an orientation point, then follow its citations and revision history. Names, dates and institutional relationships should be checked against the original record.

Best used for
  • Subject orientation
  • Search vocabulary
  • Locating named sources
Verify next

The closest primary source, responsible institution and strongest cited specialist reference.

Three-step research path

  1. Establish the record: confirm the title “KOI-81”, its source revision and the description used here.
  2. Expand the search: follow KOI-81 primary sources, KOI-81 archive and KOI-81 research across catalogues and specialist indexes.
  3. Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.

Questions for further research

  1. Which source most directly establishes the central claim about “KOI-81”?
  2. Which cited source is closest to the event, object or claim?
  3. What terminology or title could unlock a more precise catalogue search?
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Source & attribution

This entry incorporates text from “KOI-81” 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.