4 Cygni
star in the constellation Cygnus
4 Cygni is a binary star system in the northern constellation of Cygnus. It is a faintly visible to the naked eye with an apparent visual magnitude of 5.17. The distance to 4 Cygni, as determined from its annual parallax shift of 5.8 mas, is about 560 light years.
This is single-lined spectroscopic binary with an orbital period of 35 days and an eccentricity of 0.45. The visible component is a B-type star with a stellar classification of B8p Si (Fe II), where the suffix notation indicates this is type of chemically peculiar star known as a silicon star. It displays an overabundance of iron in the visual spectrum, while the star appears helium-weak in the ultraviolet.
John Ernest Winzer announced that 4 Cygni is a low amplitude variable star, in his 1974 Ph.D. thesis. It was given its variable star designation, V1741 Cygni, in 1981. 4 Cygni A is an Alpha2 Canum Venaticorum variable that varies by 0.02 magnitude over a period of 0.68674 days. The average quadratic field strength of the magnetic field is (254.7±57.2)×10−4 T. With an age of 145 million years, it has four times the mass of the Sun and five times the Sun's radius.
“4 Cygni” enters the record as star in the constellation Cygnus. Crown Archives preserves that source wording while asking what Cygni, star and constellation can confirm, complicate or overturn.
Why this record matters
“4 Cygni” is worth following because a concise public description often conceals a longer documentary argument. Here, Cygni, star and constellation provides the most credible route into that argument.
Named sources, stable identifiers and responsible institutions provide the strongest route from overview to verifiable evidence. The source revision retrieved here is dated Dec 17, 2025. The linked authority identifier is Q6693793. None of the 0 selected statements returned an explicit reference. The first chronological checks are 1974 and 1981.
Overview language is designed for orientation and should not be treated as a substitute for the evidence cited beneath it. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. 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.
- Subject orientation
- Search vocabulary
- Locating named sources
The closest primary source, responsible institution and strongest cited specialist reference.
Three-step research path
- Establish the record: confirm the title “4 Cygni”, its source revision and the description used here.
- Expand the search: follow 4 Cygni primary sources, 4 Cygni archive and Cygni research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
- Which source most directly establishes the central claim about “4 Cygni”?
- Which institution is responsible for the underlying evidence?
- What terminology or title could unlock a more precise catalogue search?
Search terms from this dossier
This entry incorporates text from “4 Cygni” 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.