21 Sagittarii is a double bright giant star in the constellation of Sagittarius.
21 Sagittarii visual magnitude is 4.81. Because of its moderate brightness, 21 Sagittarii 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 21 Sagittarii:
Celestial coordinates and finder chart of 21 Sagittarii
21 Sagittarii 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 21 Sagittarii are provided in the following table:
The simplified sky map below shows the position of 21 Sagittarii in the sky:
Visibility of 21 Sagittarii from your location
Digitized Sky Survey image of 21 Sagittarii
The image below is a photograph of 21 Sagittarii 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 21 Sagittarii is 0.006 arcsec per year in Right Ascension and -0.025 arcsec per year in Declination and the associated displacement for the next 10000 years is represented with the red arrow.
Distance of 21 Sagittarii from the Sun and relative movement
21 Sagittarii is distant 597.07 light years from the Sun and it is moving towards the Sun at the speed of 12 kilometers per second.
Spectral properties of 21 Sagittarii
21 Sagittarii belongs to spectral class K2 and has a luminosity class of II corresponding to a bright giant star.
The red dot in the diagram below shows where 21 Sagittarii is situated in the Hertzsprung–Russell diagram.
21 Sagittarii star system properties
21 Sagittarii is a visual double star which can be observed with the help of medium or large telescopes. The table below shows key information about the 21 Sagittarii double sysyem: