Phi3 Hydrae
binary star system in the constellation Hydra
Phi3 Hydrae (φ3 Hya) is a binary star in the equatorial constellation of Hydra. It originally received the Flamsteed designation of 2 Crateris before being placed in the Hydra constellation. Based upon an annual parallax shift of 15.49 mas as seen from Earth, it is located around 211 light years from the Sun. It is visible to the naked eye with an apparent visual magnitude of 4.90. It forms a triangle with the fainter φ1 Hydrae and φ2 Hydrae, between μ Hydrae and ν Hydrae.
This is a single-lined spectroscopic binary star system with an orbital period of about 1,200 days and an eccentricity of 0.1. The primary, component A, is an evolved G-type giant star with a stellar classification of G8 III. It is a red clump star, which means it is generating energy through the fusion of helium at its core. The star has twice the mass of the Sun and has expanded to 9 times the Sun's radius.
“Phi3 Hydrae” enters the record as binary star system in the constellation Hydra. Crown Archives preserves that source wording while asking what Phi3, Hydrae and binary can confirm, complicate or overturn.
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This entry incorporates text from “Phi3 Hydrae” 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.