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public LocationGreenwich, UK
Sunrise: 4:57 
Transit: 13:04 
Sunset: 21:10
wb_twilight   (Civil Twilight)   What's Visible Now?
All Constellations » Perseus » 

θ Persei (theta Persei)

Above the horizon.  Circumpolar today
Altitude: 12.6°   Azimuth: 15.2°   Direction: North-North-East

θ Persei is a variable and multiple main-sequence star of spectral class F8 in the constellation of Perseus.

θ Persei visual magnitude is 4.12. Because of its moderate brightness, θ Persei is easily visible to the naked eye from locations with dark skies, while it might be barely visible, or not visible at all, from light-polluted skies.

θ Persei is situated north of the celestial equator, as such, it is more easily visible from the northern hemisphere.

Image of θ Persei (theta Persei) star
DSS2 image of θ Persei. The red arrow shows the motion of θ Persei during the next 1000 years (5.60 arcmin in Right Ascension and -1.48 arcmin in declination);

Apparent Coordinates

02h 45m 52s
+49° 19’ 51”

J2000 Coordinates

02h 44m 12s
+49° 13’ 41”

Galactic Coordinates


Finder Chart

Finder chart θ Persei (theta Persei) star
Simplified finder chart for θ Persei (theta Persei).

Magnitude, Color, Spectral Class



The red dot in the diagram below shows where θ Persei is situated in the Hertzsprung–Russell diagram.

HR Diagram
H-R diagram showing the position of θ Persei. Attribution: Richard Powell / CC BY-SA

Star System Properties

θ Persei is a visual double star which can be observed with the help of small or medium telescopes. The table below shows key information about the θ Persei double sysyem:

19.6 arcsec

Distance, Radial Speed, Proper Motion

θ Persei is distant 36.62 light years from the Sun and it is moving far from the Sun at the speed of 25 kilometers per second.

11.23 pc
36.62 ly
25 km/s
0.336 arcsec/y
-0.089 "/y

Alternative Designations

θ Persei
(theta Persei)
Gl 107 A

Visibility from Your Location

θ Persei (theta Persei) is circumpolar and transits at 07:21 UTC (altitude: 87.7°)