30 Piscium
variable star in the constellation Pisces
30 Piscium (HIP 154) is a solitary variable star in the zodiac constellation of Pisces. It is visible to the naked eye with an apparent visual magnitude of 4.37. Its calculated mid-value of antiposed parallax shift as the Earth moves around the Sun of very roughly 7.88 mas, makes it around 410 light years away. Its net movement in the present epoch is one of moving closer – radial velocity (speed away from our star system) is −12 km/s.
This is an aging red giant star with a stellar classification of M3 III, indicating it has exhausted the hydrogen at its core and evolved off the main sequence. It is a candidate long-period variable star and has been given the designation YY Psc. It varies in brightness between magnitudes 4.31 and 4.41 with no clear period. Possible periods of 23.1, 32.0, 53.6, and 167.8 days have been identified.
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This entry incorporates text from “30 Piscium” 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.