Your guide to the Solar System and the night sky
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🌎  Observing from: Greenwich, United Kingdom [change]

30 Geminorum

30 Geminorum is a double hypergiant star in the constellation of Gemini.

30 Geminorum visual magnitude is 4.49. Because of its moderate brightness, 30 Geminorum 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 30 Geminorum:

30 Geminorum is below the horizon from Greenwich, United Kingdom [change].

Celestial coordinates and finder chart of 30 Geminorum

30 Geminorum 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 30 Geminorum are provided in the following table:

06h 43m 59s
+13° 13’ 40”

The simplified sky map below shows the position of 30 Geminorum in the sky:

Finder chart 30 Geminorum star
Simplified finder chart for 30 Geminorum.

Visibility of 30 Geminorum from your location

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

Today's 30 Geminorum rise, transit and set times from Greenwich, United Kingdom [change] are the following (all times relative to the local timezone Europe/London):

Azimuth: 76.8°
Max altitude: 51.7°
Azimuth: 283.2°
30 Geminorum is below the horizon from Greenwich, United Kingdom

Digitized Sky Survey image of 30 Geminorum

The image below is a photograph of 30 Geminorum 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 30 Geminorum is -0.003 arcsec per year in Right Ascension and -0.058 arcsec per year in Declination and the associated displacement for the next 10000 years is represented with the red arrow.

Image of 30 Geminorum star
DSS2 image of 30 Geminorum. The red arrow shows the motion of 30 Geminorum during the next 10000 years (-0.50 arcmin in Right Ascension and -9.67 arcmin in declination);

Distance of 30 Geminorum from the Sun and relative movement

30 Geminorum is distant 275.80 light years from the Sun and it is moving far from the Sun at the speed of 14 kilometers per second.

84.60 pc
275.80 ly
14 km/s
-0.003 arcsec/year
-0.058 arcsec/year

Spectral properties of 30 Geminorum

30 Geminorum belongs to spectral class K0 and has a luminosity class of III corresponding to a hypergiant star.


The red dot in the diagram below shows where 30 Geminorum is situated in the Hertzsprung–Russell diagram.

HR Diagram
H-R diagram showing the position of 30 Geminorum. Attribution: Richard Powell / CC BY-SA

30 Geminorum star system properties

30 Geminorum 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 30 Geminorum double sysyem:

27.2 arcsec

Alternative designations of 30 Geminorum

30 Geminorum