μ Pictoris, Latinised as Mu Pictoris, is a binary star system in the southern constellation

Pictor Pictor is a constellation in the Southern Celestial Hemisphere, located between the star Canopus and the Large Magellanic Cloud. Its name is Latin for painter, and is an abbreviation of the older name Equuleus Pictoris (the "painter's easel ...

. It is bright enough to be dimly visible to the naked eye, having a combined

apparent visual magnitude Apparent magnitude () is a measure of the brightness of a star or other astronomical object observed from Earth. An object's apparent magnitude depends on its intrinsic luminosity, its distance from Earth, and any extinction of the object's lig ...

of 5.69. Based upon an annual parallax shift of 4.31 mas as seen from Earth, the system is located roughly 760 light years distant from the

Sun The Sun is the star at the center of the Solar System. It is a nearly perfect ball of hot plasma, heated to incandescence by nuclear fusion reactions in its core. The Sun radiates this energy mainly as light, ultraviolet, and infrared radi ...

. As of 2010, the pair have an angular separation of 2.46

arc second A minute of arc, arcminute (arcmin), arc minute, or minute arc, denoted by the symbol , is a unit of angular measurement equal to of one degree. Since one degree is of a turn (or complete rotation), one minute of arc is of a turn. The n ...

s along a

position angle In astronomy, position angle (usually abbreviated PA) is the convention for measuring angles on the sky. The International Astronomical Union defines it as the angle measured relative to the north celestial pole (NCP), turning positive into the ...

of 221°. The primary, designated component A, is a blue-white star with a visual magnitude of 5.71 and a stellar classification of B9 Ve or B9 IVn. The first classification suggests is a

B-type main-sequence star A B-type main-sequence star (B V) is a main-sequence (hydrogen-burning) star of spectral type B and luminosity class V. These stars have from 2 to 16 times the mass of the Sun and surface temperatures between 10,000 and 30,000 K. B-type star ...

, with the 'e' suffix indicating a

Be star Be stars are a heterogeneous set of stars with B spectral types and emission lines. A narrower definition, sometimes referred to as ''classical Be stars'', is a non-supergiant B star whose spectrum has, or had at some time, one or more Balmer e ...

. The second may instead indicate a somewhat more

evolved Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variation ...

B-type star A B-type main-sequence star (B V) is a main-sequence (hydrogen-burning) star of spectral type B and luminosity class V. These stars have from 2 to 16 times the mass of the Sun and surface temperatures between 10,000 and 30,000 K. B-type star ...

that is spinning rapidly, resulting in "nebulous" absorption lines. Photometrically, it shows a pulsation period of 0.397 days, which is likely the same as the rotation period. The secondary companion, component B, is a white-hued star of magnitude 9.43 with a classification of A8 V:p?. This indicates it is an

A-type main-sequence star An A-type main-sequence star (A V) or A dwarf star is a main-sequence (hydrogen-burning) star of spectral type A and luminosity class V (five). These stars have spectra defined by strong hydrogen Balmer absorption lines. They measure between ...

, with the 'p?' suffix suggesting it may be chemically peculiar while the ':' notation says there is some uncertainty about the general classification.

References

{{DEFAULTSORT:Mu Pictoris B-type subgiants B-type main-sequence stars A-type main-sequence stars Binary stars Pictor Pictoris, Mu 046860 031137 2412 Durchmusterung objects