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.
[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.
[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.