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A Complete Guide to the Solar System and the Night Sky
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public Observing fromLocation: Greenwich, United Kingdom edit_location_alt
SunriseRise: 6:04  
clear_day Transit: 12:06  
SunsetSet: 18:09
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All Constellations » Scorpius » 

Acrab - β1 Scorpii (beta1 Scorpii)

Altitude: 18.5°   Azimuth: 173.9°   Direction: South

Acrab, also designated as β1 Scorpii (beta1 Scorpii), is a variable and multiple main-sequence star in the constellation of Scorpius.

Acrab visual magnitude is 2.62. Thanks to its high brightness, Acrab is clearly visible when observed from locations with dark skies, and should be also quite easily visible from light polluted areas.

The proper motion of Acrab is -0.006 arcsec per year in Right Ascension and -0.019 arcsec per year in Declination and the associated displacement for the next 10000 years is represented with the red arrow.

Image of Acrab - β1 Scorpii (beta1 Scorpii) star
DSS2 image of Acrab. The red arrow shows the motion of Acrab during the next 10000 years (-1.00 arcmin in Right Ascension and -3.17 arcmin in declination);

Key facts about Acrab

2.62
Main-sequence

Acrab - β1 Scorpii (beta1 Scorpii) is above the horizon from Greenwich, United Kingdom edit_location_alt.

Altitude: 18.5°
Azimuth: 173.9°
Direction: South

Celestial coordinates and finder chart of Acrab

Acrab 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 Acrab are provided in the following table:

16h 05m 26s
-19° 48’ 20”
353.19°
23.6°
Scorpius

The simplified sky map below shows the position of Acrab in the sky:

Finder chart Acrab - β1 Scorpii (beta1 Scorpii) star
Simplified finder chart for Acrab - β1 Scorpii (beta1 Scorpii).

Visibility of Acrab 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 Acrab - β1 Scorpii (beta1 Scorpii) 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: 109.8°
Max altitude: 18.7°
Azimuth: 250.2°

Distance of Acrab from the Sun and relative movement

Acrab is distant 530.08 light years from the Sun and it is moving towards the Sun at the speed of 1 kilometers per second.

162.60 pc
530.08 ly
-1 km/s
-0.006 arcsec/year
-0.019 arcsec/year

Spectral properties of Acrab

Acrab belongs to spectral class B1 and has a luminosity class of V corresponding to a main-sequence star.

-3.44
B1V
11092K

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

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

Acrab star system properties

Acrab 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 Acrab double sysyem:

2.62
3.92
1.3
0 arcsec

Alternative designations of Acrab

Acrab
β1 Scorpii
(beta1 Scorpii)
SAO159682
SAO159682