SDSS J0815+4729

Ultra-low metallicity star in the constellation Lynx

SDSS J0815+4729
Observation data Epoch J2000 Equinox J2000
Constellation	Lynx
Right ascension	08^h 15^m 54.26778^s^[1]
Declination	+47° 29′ 47.6013″^[1]
Characteristics
Evolutionary stage	main-sequence star
Spectral type	F5V^[2]
Astrometry

Radial velocity (R_v)	-108^[2] km/s
Proper motion (μ)	RA: -14.257 mas/yr^[1] Dec.: -24.214 mas/yr^[1]
Parallax (π)	0.4089 ± 0.0685 mas^[1]
Distance	approx. 8,000 ly (approx. 2,400 pc)

Details^[3]

Surface gravity (log g)	4.7 ± 0.6 cgs
Temperature	6142 ± 118 K
Metallicity [Fe/H]	−5.49±0.14^[4] dex

Other designations
SDSS J081554.26+472947.5, Gaia DR2 931227322991970560
Database references
SIMBAD	data

SDSS J081554.26+472947.5, often abbreviated to its partial coordinates, J0815+4729, is a star with an ultra-low metallicity in the constellation of Lynx. It also has a relatively high concentration of carbon.^[3] The surface of the star has temperature 6,215 K. It is at a distance of 7,500 light years (2.3 kiloparsecs) from the Sun, and is 33,000 light-years (10 kiloparsecs) from the Galactic Center.^[3] Its [Fe/H] was first believed to be below –5.8 dex, making it the lowest metallicity un-evolved star detected.,^[3] but was revised to -5.49 dex in 2020.^[4]

J0815+4729's ratio of carbon to iron, [C/Fe] is at least 5.0 dex.^[3] The star is also heavily enriched in nitrogen and oxygen, originating from primordial gas cloud contaminated by single zero-metallicity supernova. The lack of heavy elements, including iron, is explained by these mostly falling back to collapsing supernova remnant.^[4]

References

^ ^a ^b ^c ^d Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
^ ^a ^b "SDSS J081554.26+472947.5". SIMBAD. Centre de données astronomiques de Strasbourg.
^ ^a ^b ^c ^d ^e Aguado, David S; Hernández, Jonay I. González; Prieto, Carlos Allende; Rebolo, Rafael (2018). "J0815+4729: A Chemically Primitive Dwarf Star in the Galactic Halo Observed with Gran Telescopio Canarias". The Astrophysical Journal. 852 (1): L20. arXiv:1712.06487. Bibcode:2018ApJ...852L..20A. doi:10.3847/2041-8213/aaa23a. S2CID 119423051.
^ ^a ^b ^c Hernández, Jonay I. González; Aguado, David S.; Prieto, Carlos Allende; Burgasser, Adam J.; Rebolo, Rafael (2020), "The Extreme CNO-enhanced Composition of the Primitive Iron-poor Dwarf Star J0815+4729", The Astrophysical Journal, 889 (1): L13, arXiv:2001.07257, Bibcode:2020ApJ...889L..13G, doi:10.3847/2041-8213/ab62ae, S2CID 210839093

Constellation of Lynx

Stars

Bayer	α ψ¹⁰ Aur (16)
Flamsteed	1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 (Alsciaukat) 32 33 34 35 36 38 42 43 44 Cam 45 Cam 46 Cam 48 Cam 50 Cam 52 Cam 54 Cam 5 LMi 10 UMa 19 UMa
Variable	R T U Y RR SW SZ TT TV TZ UU UV UX UY AN BE BF BH BK CC CY DD DI DU
HR	2463 2486 2561 2642 2645 2721 2737 2751 2776 2804 2844 2894 2903 2914 2915 2935 2939 3028 3039 3094 3106 3130 3175 3181 3200 3246 3258 3277 3287 3292 3309 3348 3351 3360 3509 3511 3545 3546 3580 3586 3612 3625 3686 3701 3809
HD	44061 48948 52859 58681 59721 59826 63588 63630 65392 67539 75898 (Stribor)
Other	GD 98 Gliese 277 GJ 1105 GJ 3421 HS 0702+6043 IRC +60169 J0815+4729 PG 0859+415 WASP-13 (Gloas) XO-2 XO-4 (Koit) XO-5 (Absolutno)

Exoplanets	6 Lyncis b WASP-13b (Cruinlagh) XO-2Nb XO-4b (Hämarik) XO-5b (Makropulos)

Star clusters	NGC 2666

Nebulae	Jones-Emberson 1 Lynx Arc

Galaxies

NGC	2273 2273B 2308 2315 2320 2321 2322 2326 2326A 2329 2330 2332 2337 2340 2344 2415 2424 2426 2429 2429A 2429B 2431 2444 2445 2446 2456 2457 2458 2461 2462 2463 2468 2469 2472 2473 2474 2475 2476 2484 2488 2493 2495 2497 2500 2505 2518 2519 2521 2524 2528 2532 2534 2537 2537A 2541 2543 2549 2552 2638 2649 2668 2683 2691 2704 2712 2719 2719A 2724 2746 2755 2759 2770 2776 2778 2779 2780 2782 2785 2793 2798 2799 2823 2825 2826 2827 2828 2829 2830 2831 2832 2833 2834 2838 2839 2840 2844 2852 2853 2860
Other	3C 171 APM 08279+5255 SDSS J082535.19+512706.3 IC 2233 IRAS 09104+4109 UGC 4653 UGC 4881 UGC 4904

NGC