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public Observing fromLocation: Greenwich, United Kingdom edit_location_alt
SunriseRise: 6:38  
clear_day Transit: 12:10  
SunsetSet: 17:43
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All Constellations » Musca » 

θ Muscae (theta Muscae)

Altitude: -57.5°   Azimuth: 138.0°   Direction: South-East

θ Muscae is a variable and double hypergiant star in the constellation of Musca.

θ Muscae visual magnitude is 5.51. Because of its reltive faintness, θ Muscae should be visible only from locations with dark skies, while it is not visible at all from skies affected by light pollution.

The proper motion of θ Muscae is -0.016 arcsec per year in Right Ascension and -0.009 arcsec per year in Declination and the associated displacement for the next 10000 years is represented with the red arrow.

Image of θ Muscae (theta Muscae) star
DSS2 image of θ Muscae. The red arrow shows the motion of θ Muscae during the next 10000 years (-2.67 arcmin in Right Ascension and -1.50 arcmin in declination);

Key facts about θ Muscae


θ Muscae (theta Muscae) is below the horizon from Greenwich, United Kingdom edit_location_alt.

Altitude: -57.5°
Azimuth: 138.0°
Direction: South-East

Celestial coordinates and finder chart of θ Muscae

θ Muscae is situated south of the celestial equator, as such, it is more easily visible from the southern hemisphere. Celestial coordinates for the J2000 equinox as well as galactic coordinates of θ Muscae are provided in the following table:

13h 08m 07s
-65° 18’ 23”

The simplified sky map below shows the position of θ Muscae in the sky:

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

Visibility of θ Muscae from your location

Location: Greenwich, United Kingdom edit_location_alt
Latitude: 51° 28’ 47” N
Longitude: 0° 00’ 00” E
Timezone: Europe/London

θ Muscae (theta Muscae) is currently not visible from Greenwich, United Kingdom edit_location_alt

Distance of θ Muscae from the Sun and relative movement

θ Muscae is distant 108,666.67 light years from the Sun and it is moving towards the Sun at the speed of 28 kilometers per second.

33,333.33 pc
108,666.67 ly
-28 km/s
-0.016 arcsec/year
-0.009 arcsec/year

Spectral properties of θ Muscae

θ Muscae belongs to spectral class B0 and has a luminosity class of I corresponding to a hypergiant star.


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

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

θ Muscae star system properties

θ Muscae 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 Muscae double sysyem:

5.3 arcsec

Alternative designations of θ Muscae

θ Muscae
(theta Muscae)