4 Centauri

4 Centauri is a double sub-giant star in the constellation of Centaurus.

4 Centauri visual magnitude is 4.73. Because of its moderate brightness, 4 Centauri 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 4 Centauri:

Color of 4 Centauri ⬤

Magnitude of 4 Centauri 4.73

Class Sub-giant

VISIBILITY RIGHT NOW 4 Centauri is above the horizon from Greenwich, United Kingdom edit_location_alt. Altitude: 4°.

Celestial coordinates and finder chart of 4 Centauri

4 Centauri 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 4 Centauri are provided in the following table:

Right Ascension J2000 13h 53m 12s

Declination J2000 -31° 55’ 40”

Galactic Longitude 317.93°

Galactic Latitude 29.14°

Constellation Centaurus

The simplified sky map below shows the position of 4 Centauri in the sky:

Simplified finder chart for 4 Centauri.

Visibility of 4 Centauri from your location

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

Today's 4 Centauri rise, transit and set times from Greenwich, United Kingdom edit_location_alt are the following (all times relative to the local timezone Europe/London):

Azimuth: 121.9° RISE 19:59

Max altitude: 6.6° TRANSIT 22:32

Azimuth: 238.1° SET 1:09

RIGHT NOW 4 Centauri is above the horizon from Greenwich, United Kingdom

Digitized Sky Survey image of 4 Centauri

The image below is a photograph of 4 Centauri 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 4 Centauri is -0.015 arcsec per year in Right Ascension and -0.012 arcsec per year in Declination and the associated displacement for the next 10000 years is represented with the red arrow.

DSS2 image of 4 Centauri. The red arrow shows the motion of 4 Centauri during the next 10000 years (-2.50 arcmin in Right Ascension and -2.00 arcmin in declination);

Distance of 4 Centauri from the Sun and relative movement

4 Centauri is distant 669.40 light years from the Sun and it is moving far from the Sun at the speed of 5 kilometers per second.

Distance (parsec) 205.34 pc

Distance (light year) 669.40 ly

Heliocentric radial velocity 5 km/s

Proper Motion RA -0.015 arcsec/year

Proper Motion Dec -0.012 arcsec/year

Spectral properties of 4 Centauri

4 Centauri belongs to spectral class B4 and has a luminosity class of IV corresponding to a sub-giant star.

Absolute magnitude -1.83

Spectral Type B4IV

Color Index (B-V) -0.14

Temperature of 4 Centauri 12293K

The red dot in the diagram below shows where 4 Centauri is situated in the Hertzsprung–Russell diagram.

H-R diagram showing the position of 4 Centauri. Attribution: Richard Powell / CC BY-SA

4 Centauri star system properties

4 Centauri 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 4 Centauri double sysyem:

Main star magnitude 4.73

Secondary star magnitude 8.43

Magnitude difference 3.7

Separation 14.9 arcsec

Alternative designations of 4 Centauri

Flamsteed designation 4 Centauri

Henry Draper Catalogue HD120955

SAO Catalogue SAO204944

Hipparcos Catalogue HIP67786

Durchmusterung Catalogue CD-3110729

In Evidence

Other stars in Centaurus