21 Persei is a variable star in the constellation of Perseus.
21 Persei visual magnitude is 5.11. Because of its reltive faintness, 21 Persei should be visible only from locations with dark skyes, while it is not visible at all from skyes affected by light pollution.
The table below summarizes the key facts about 21 Persei:
Celestial coordinates and finder chart of 21 Persei
21 Persei is situated north of the celestial equator, as such, it is more easily visible from the northern hemisphere. Celestial coordinates for the J2000 equinox as well as galactic coordinates of 21 Persei are provided in the following table:
The simplified sky map below shows the position of 21 Persei in the sky:
Visibility of 21 Persei from your location
Digitized Sky Survey image of 21 Persei
The image below is a photograph of 21 Persei 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 Persei is 0.003 arcsec per year in Right Ascension and -0.031 arcsec per year in Declination and the associated displacement for the next 10000 years is represented with the red arrow.
Distance of 21 Persei from the Sun and relative movement
21 Persei is distant 386.71 light years from the Sun and it is moving far from the Sun at the speed of 8 kilometers per second.
Spectral properties of 21 Persei
The red dot in the diagram below shows where 21 Persei is situated in the Hertzsprung–Russell diagram.