Polis - μ Sagittarii (mu Sagittarii)
Polis, also designated as μ Sagittarii (mu Sagittarii), is a variable and multiple supergiant star in the constellation of Sagittarius.
Polis visual magnitude is 3.86. Because of its moderate brightness, Polis should be easily visible from locations with dark skyes, while it can be barely visible, or not visible at all, from skyes affected by light pollution.
The table below summarizes the key facts about Polis:
Celestial coordinates and finder chart of Polis
Polis is situated close to the celestial equator, as such, it is at least partly visible from both hemispheres in certain times of the year. Celestial coordinates for the J2000 equinox as well as galactic coordinates of Polis are provided in the following table:
The simplified sky map below shows the position of Polis in the sky:
Visibility of Polis from your location
Digitized Sky Survey image of Polis
The image below is a photograph of Polis from the Digitized Sky Survey 2 (DSS2 - see the credits section) taken in the red channel. The area of sky represented in the image is 0.5x0.5 degrees (30x30 arcmins). The proper motion of Polis is 0.002 arcsec per year in Right Ascension and 0.001 arcsec per year in Declination and the associated displacement for the next 100000 years is represented with the red arrow.
Distance of Polis from the Sun and relative movement
Polis is distant 29,636.36 light years from the Sun and it is moving towards the Sun at the speed of 6 kilometers per second.
Spectral properties of Polis
Polis belongs to spectral class B8 and has a luminosity class of I corresponding to a supergiant star.
The red dot in the diagram below shows where Polis is situated in the Hertzsprung–Russell diagram.
Polis star system properties
Polis is a visual double star which can be observed only with the help of very large telescopes. The table below shows key information about the Polis double sysyem: