}}{{Starbox reference
| Simbad = HD+21447
}}{{Starbox end}}HD 21447 (or D Camelopardalis), is a probable binary star[19] system located in the constellation Camelopardalis. The star is also known as HR 1046. It can be viewed with the naked eye, having an apparent visual magnitude of 5.09.[3] Based upon an annual parallax shift of {{Val|16.42|0.29|ul=mas}},[1] it is located some 199 light years from the Sun. It is a candidate for membership in the Ursa Major Moving Group.[22]The primary component is A-type main-sequence star with a stellar classification of A1 Va.[4] It is around 146[14] million years old and is spinning with a projected rotational velocity of 182 km/s.[14] The star has an estimated 2.32[11] times the mass of the Sun and about 1.9[12] times the Sun's radius. It is radiating around 32[3] times the Sun's luminosity from its photosphere at an effective temperature of 10,049 K.[14] The companion is visual magnitude 9.4 star at an angular separation of {{Val|14.8|ul=arcsec}}.[19]
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