HE1327-2326

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**HE1327-2326**
Observation data Epoch J2000.0 (ICRS)
Constellation (pronunciation)	Hydra
Right ascension	13^h 30^m 06^s^[1]
Declination	-23° 41′ 54″^[1]
Astrometry
Spectral type	K5+III/dM2 V
Apparent magnitude (V)	13.5
Distance	4.000 Light year
Details
Mass	< 1 M_☉
Radius	? R_☉
Luminosity	? L_☉
Temperature	? K
Metallicity	?
Rotation	?
Age	13.6 Million years
Other designations
HE 1327-2326, SPM3.2 4266486.

HE1327-2326, discovered in 2005, is the star with the lowest known iron abundance to date. The star is a member of Population II, with an iron to hydrogen ratio ([Fe/H]), or metallicity, of -5.6. This number indicates that its iron content is 300,000 times less than that of the Earth's sun. However, it has a carbon abundance of roughly one-tenth solar, [C/H] = -1.0, and it is not known how these two abundances can be produced simultaneously. Discovered by the Hamburg/ESO survey for metal-poor stars, it was probably formed during an age of the universe when the metal content was much lower. It's been speculated that this star is part of the second generation, born out of the gas clouds which were polluted by the primordial Population III stars.

[edit] See also

HE0107-5240

[edit] References

^ ^a ^b The Optical Gravitational Lensing Experiment. Additional Planetary and Low-Luminosity Object Transits from the OGLE 2001 and 2002 Observational Campaigns, A. Udalski, G. Pietrzynski, M. Szymanski, M. Kubiak, K. Zebrun, I. Soszynski, O. Szewczyk, and L. Wyrzykowski, Acta Astronomica 53 (June 2003), pp. 133–149.

FREBEL A., AOKI W., CHRISTLIEB N., ANDO H., ASPLUND M., BARKLEM P.S., BEERS T.C., ERIKSSON K., FECHNER C., FUJIMOTO M.Y., HONDA S., KAJINO T., MINEZAKI T., NOMOTO K., NORRIS J.E., RYAN S.G., TAKADA-HIDAI M., TSANGARIDES S., YOSHII Y., Nucleosynthetic signatures of the first stars, Nature, 434, 871-873 (2005)