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A fifth-magnitude star in the central regions of Canis Major, Pi Canis Majoris lies southward and a little eastward of brilliant Sirius, with the open cluster M41 falling a little over two degrees to its west. The Pi Canis Majoris system lies some 97 light years from the Sun, and its motion through the Galaxy is bringing the two stars gradually closer together.

Pi Canis Majoris is the brightest of a trio of stars in the central parts of Canis Major. To the west is blue 15 Canis Majoris, while the more southerly star of the three is 17 Canis Majoris. These stars are in fact unrelated to one another, and both 15 and 17 are more intrinsically luminous than Pi, but also much more distant from the Solar System. Imagery provided by Aladin sky atlas

This is a binary system, with a bright yellow F-type star as its primary. This primary star, Pi Canis Majoris A, is a dwarf like the Sun, but somewhat hotter, more massive and more luminous. It is also a variable, showing slight but regular changes in its brightness over a period of approximately two hours, and appears to be surrounded by a disc of matter. Pi Canis Majoris B is its much fainter companion star, estimated to orbit at a distance of some 340 AU from the primary.


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