BN Camelopardalis is a suspected

astrometric binary A binary star is a system of two stars that are gravitationally bound to and in orbit around each other. Binary stars in the night sky that are seen as a single object to the naked eye are often resolved using a telescope as separate stars, in wh ...

in the northern circumpolar constellation of

Camelopardalis Camelopardalis is a large but faint constellation of the northern sky representing a giraffe. The constellation was introduced in 1612 or 1613 by Petrus Plancius. Some older astronomy books give Camelopardalus or Camelopardus as alternative for ...

. It appears as a variable star that is visible to the naked eye as a dim, white-hued point of light with an apparent visual magnitude that fluctuates around 5.49. The system is located at a distance of around 310

light year A light-year, alternatively spelled light year, is a large unit of length used to express astronomical distances and is equivalent to about 9.46 trillion kilometers (), or 5.88 trillion miles ().One trillion here is taken to be 1012 ...

s from the Sun based on

parallax Parallax is a displacement or difference in the apparent position of an object viewed along two different lines of sight and is measured by the angle or semi-angle of inclination between those two lines. Due to foreshortening, nearby objects ...

, and is drifting further away with a

radial velocity The radial velocity or line-of-sight velocity, also known as radial speed or range rate, of a target with respect to an observer is the temporal rate of change, rate of change of the distance or Slant range, range between the two points. It is e ...

of +9 km/s. The visible component is a weakly magnetic chemically peculiar star with a

stellar classification In astronomy, stellar classification is the classification of stars based on their stellar spectrum, spectral characteristics. Electromagnetic radiation from the star is analyzed by splitting it with a Prism (optics), prism or diffraction grati ...

of B9.5VpSi, matching a B-type main-sequence star with an anomalous abundance of silicon. It is a variable star that ranges in brightness from 5.34 down to 5.58. Samus et al. (2017) have it categorized as an α² Canum Venaticorum variable with a period of 2.7347 days, while Adelman and Sutton (2007) found a period of 2.73501 days. The star has three times the mass and radius of the Sun and is radiating 110 times the Sun's luminosity from its

photosphere The photosphere is a star's outer shell from which light is radiated. The term itself is derived from Ancient Greek roots, φῶς, φωτός/''phos, photos'' meaning "light" and σφαῖρα/''sphaira'' meaning "sphere", in reference to it ...

at an

effective temperature The effective temperature of a body such as a star or planet is the temperature of a black body that would emit the same total amount of electromagnetic radiation. Effective temperature is often used as an estimate of a body's surface temperature ...

of 11,561 K.

References

{{DEFAULTSORT:BN Camelopardalis B-type main-sequence stars Ap stars Alpha2 Canum Venaticorum variables Camelopardalis Durchmusterung objects 032650 024254

1643 Events January–March * January 21 – Abel Tasman sights the island of Tonga. * February 6 – Abel Tasman sights the Fiji Islands. * March 13 – First English Civil War: First Battle of Middlewich – Roundheads ...

Camelopardalis, BN