Stellar habitability in our neighbourhood focuses on long‑lived K‑type stars.

Astronomers completed a census of more than 2,000 nearby K‑type stars and obtained detailed spectra for 580 within 33 parsecs, identifying 529 mature, inactive K dwarfs as useful targets for terrestrial planet searches.

Researchers completed a census of more than 2,000 K‑type stars near the Sun and obtained detailed spectra for hundreds of them. The team presented the results at the 247th meeting of the American Astronomical Society and submitted a related paper to The Astronomical Journal. K‑type stars are cooler than the Sun and can live tens of billions of years, which makes them of interest for studies of exoplanet habitability. The study emphasizes identifying mature, quiescent K dwarfs that exhibit lower flare activity than many red dwarfs. Key findings: - The survey examined over 2,000 K‑type stars and produced spectroscopic characterizations for 580 K dwarfs within 33 parsecs, using the CHIRON spectrograph on the SMARTS 1.5m telescope and the TRES spectrograph on the Tillinghast Telescope. - The researchers identified 529 mature, inactive K dwarfs as promising targets for searches for terrestrial planets. - According to the NASA Exoplanet Archive, 44 of the 580 stars (about 7.5%) are known to host confirmed exoplanets. - The sample’s galactic distribution is reported as 464 stars in the thin disk, 107 in the thick disk, and one in the halo. - K dwarfs make up about 11% of stars within 33 parsecs, can live roughly 20–70 billion years, and produce less extreme ultraviolet radiation and less flare activity than typical M dwarfs. - The study notes that K dwarfs are under‑represented in exoplanet surveys largely because of observational biases: Sun‑like stars are brighter and M dwarfs offer more favourable planet‑to‑star detection ratios. Summary: The census produces a catalog of nearby K dwarfs with ages, rotations, temperatures, metallicities, and galactic locations that can guide follow‑up observations and target selection for exoplanet habitability research. The authors describe the dataset as a lasting resource for studies of nearby stars and for future searches aimed at terrestrial planets. Undetermined at this time.