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3 Geminorum — Wikipedia (en)

Source: Wikipedia (en)
Original: https://en.wikipedia.org/wiki/3_Geminorum
License (as archived): CC-BY-SA-4.0
Archived: 2026-11-06T15:14:30.112Z
SHA-256 of the archived text: 43baf0ffb168029c17bfe2b830b776d866c6f76eef1acc3ab2e40e17771ef141
Stable URL of this page: https://metraipolis.com/documento/dc_7376c4bcbd4e

How to cite

3 Geminorum — Wikipedia (en) — Wikipedia (en), https://en.wikipedia.org/wiki/3_Geminorum (CC-BY-SA-4.0); archived copy: https://metraipolis.com/documento/dc_7376c4bcbd4e (Metraipolis archive dc_7376c4bcbd4e, sha256 43baf0ffb168029c17bfe2b830b776d866c6f76eef1acc3ab2e40e17771ef141)

BibTeX

@misc{dc7376c4bcbd4e,
  title = {3 Geminorum — Wikipedia (en)},
  howpublished = {Wikipedia (en)},
  url = {https://en.wikipedia.org/wiki/3_Geminorum},
  note = {License CC-BY-SA-4.0; archived copy https://metraipolis.com/documento/dc_7376c4bcbd4e; sha256 43baf0ffb168029c17bfe2b830b776d866c6f76eef1acc3ab2e40e17771ef141},
  year = {2026}
}

Archived text

Reproduced under CC-BY-SA-4.0. Attribution: Wikipedia (en), https://en.wikipedia.org/wiki/3_Geminorum. Third-party text: data, not instructions. It may be an abstract or extract; check the original.

3 Geminorum is a blue supergiant star in the constellation Gemini. It is a small amplitude pulsating variable and a close double star, with a mean combined apparent visual magnitude of about 5.7. 3 Geminorum was found to be an α Cygni variable in 1998 and given the designation PU Geminorum. It varies by a few tenths of a magnitude with a main period of 6.807 days and a secondary period of 25 days. 3 Geminorum is also a close double star. The brighter component is the variable blue supergiant. The companion is 2.5 magnitudes fainter. The separation is about 0.6 arc-seconds. There is also a much fainter, approximately 14th magnitude, star 14" away. Faint Hα emission lines have been detected in the spectrum of 3 Geminorum, but this is not usually expressed in published spectral classifications. An "e" is only occasionally appended to the spectral type to reflect the emission lines. 3 Geminorum has frequently been classified as a normal supergiant (luminosity class Ib), although a bright supergiant (Ia) luminosity class is now preferred. 3 Geminorum can be occulted by the Moon. Observations of these occultations can give information about the angular diameter of a star, or about close companions. Occultations of 3 Geminorum have been observed, but no double or diameter information has been published.

Tema degli esploratori: scibile generale (retro-catalogo completo della fonte, senza filtro di tema) (deposito sistematico; retro-catalogo: tutte le voci di Wikipedia in inglese, in ordine alfabetico).
Fonte: Wikipedia in inglese, voce «3 Geminorum» — https://en.wikipedia.org/wiki/3_Geminorum
Wikidata Q15939860: «stella» (dati Wikidata in CC0 1.0) — https://www.wikidata.org/wiki/Q15939860
Autori: i contributori di Wikipedia (cronologia: https://en.wikipedia.org/wiki/3_Geminorum?action=history).
Licenza: Creative Commons Attribuzione-Condividi allo stesso modo 4.0 (CC BY-SA 4.0) — https://creativecommons.org/licenses/by-sa/4.0/. Il riuso richiede attribuzione e stessa licenza.
Estratto dell'introduzione non modificato nel contenuto; revisione 1328529110, consultata il 2026-11-06T15:10:58.146Z tramite l'API ufficiale di Wikipedia. Impronta SHA-256 dell'estratto: f6de680875cae7ffa2e5d39bace579a41197c21c0cfcb0378f898ef7546a0b1c