Beta Scorpii

Starbox begin
name = β Scorpii Starbox observe
epoch = J2000.0
constell=Scorpius
ra=16^h 05^m 26.7^s
dec=-19° 48' 20"
appmag_v = β¹; 2.56 β²; 4.90Starbox character
class = B0.5V+B2V
u-b = -0.07
b-v = -0.08
variable = ?Starbox astrometry
radial_v = -1
prop_mo_ra = -6.75
prop_mo_dec = -24.89
parallax = 6.15
p_error = 1.15
dist_ly = 530
dist_pc=163
absmag_v = β¹; -3.50 β²; -1.16Starbox detail
mass = ?
radius = 19
luminosity = 3000
temperature = β¹; 27 000 K β²; 22 000
age = ?
metal = ?
rotation = ~130 km/s.Starbox catalog
names = Acrab, Elacrab, Graffias, Grafias, Grassias, 8 Scorpii, HR 5985, HD 144218, BD-19 4308, HIP 78821, SAO 159683, GC 21610, ADS 9913, CCDM 16054-1948

Beta Scorpii (β Sco / β Scorpii) is a star system in the constellation Scorpius. It also has the traditional names Acrab, Akrab or El Acrab ( _ar. العقرب), as well as Graffias, a name it shares with Xi Scorpii. It is known as 房宿四 (the Fourth Star of the Room) in Chinese.

Observed through a small telescope, Beta Scorpii is found to be a binary star with a separation between the two components of 14 arcseconds, putting them at least 2200 Astronomical Units (AU) apart. They are both hot, B-class stars at least 10 times as massive as our own Sun, and will have short lives. Both are expected to end their stellar evolution in massive supernovae.

Beta-1 Scorpii, the brighter of the pair, has another companion 0.5 arcseconds, or about 80 AU, distant. Furthermore, both Beta-1 Scorpii and Beta-2 Scorpii, the two hot, B-class stars, are themselves thought to be spectroscopic binaries, bringing the total number of stars in the system to five.

Because it is close to the ecliptic, Beta Scorpii can be occulted by the Moon and, very rarely, by planets. The last occultation by a planet took place on 13 May 1971, by Jupiter.