Alpha Crucis (star)

α1 Crucis (A + Ab)
Spectral	B0.5 IV
Type	Subgiant
Multiple	Binary (A+Ab Components)
Luminosity	25,000 LSol
Lum Rank	45th
Absolute magnitude	−4.19
Mag Terra	1.40 (23rd)
Temperature	28,000° K
Mass	14 MSol
Companion	α1 Crucis Ab (Mass = 10 MSol)

α2 Crucis (B)
Spectral	B1 V
Type	Main Sequence
Multiple	B-Compnent (Far Companion)
Luminosity	16,000 LSol
Absolute magnitude
Mag Terra	2.09
Temperature	26,000° K

α3 Crucis (C)
Spectral	B4 IV
Type	Subgiant
Multiple	C-Compnent (Distant Companion)
Luminosity	LSol
Absolute magnitude
Mag Terra	2.09
Temperature	° K

Alpha Crucis or Acrux is a quadruple star consisting of the binary A-components α¹ [A] (B0.5 IV) and α¹ [Ab] (spectrum unknown), the B-component α² (B1 V), and the C-component α³ (B4 IV):

• α¹ [A] (B0.5 IV)
• α¹ [Ab] (spectrum unknown)
• α² [B] (B1 V)
• α³ [C] (B4 IV)

Description (Specifications)

Only two components are visually distinguishable from Terra, α¹ and α², separated by 4 arcseconds. α¹ is magnitude 1.40 and α² is magnitude 2.09, both hot class B (almost class O) stars, with surface temperatures of about 28,000 and 26,000 K respectively. Their luminosities are 25,000 and 16,000 times that of Sol. α¹ and α² orbit over such a long period that motion is only barely seen. From their minimum separation of 430AU, the period is at least 1,500 years, and may be much longer.

α¹ is itself a spectroscopic binary star, with its components thought to be around 14 and 10 times the mass of Sol and orbiting in only 76 days at a separation of about one astronomical unit. The masses of α² and the brighter component of α¹ suggest that the stars will someday explode as supernovae. The fainter component of α¹ may survive to become a massive white dwarf.

Another class-B4 subgiant, Alpha Crucis C or α³ Crucis, lies 90 arcseconds away from triple Acrux and shares Acrux's motion through space, suggesting it may be gravitationally bound to Acrux. It is therefore generally assumed to be physically associated with Acrux.

• Alpha Crucis is the 13th brightest star as seen from Terra, individually they are the 23rd (α¹) and 57th (α²) brightest star. It is the 45th brightest star in the galaxy, and one of the brightest in Charted Space. None of the Alpha Crucis stars are significantly large.

History & Background (Dossier)

The Alpha Crucis star system is approximately 99pc from Terra, and is located in a Trailing direction from Terra at bearing 300.13^o Galactic Longitude and -00.4^o South Galactic Latitude.

Image Repository

TravellerMap (T5SS):
[1]

References & Contributors (Sources)

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This page uses content from Wikipedia. The original article was at Alpha_Crucis. The list of authors can be seen in the page history. The text of Wikipedia is available under the Commons Attribution-ShareAlike 3.0 Unported License.

This list of sources was used by the Traveller Wiki Editorial Team and individual contributors to compose this article. Copyrighted material is used under license from Far Future Enterprises or by permission of the author. The page history lists all of the contributions.

• Mongoose Traveller: Solomani Alien Module 5
• EXTERNAL LINK: SIMBAD @ University of Strasbourg: [2]
• Traveller Wiki Editorial Team
• Author & Contributor: Lord & Chief Marshall (Count) Dan Corrin of the Office of the Emperor
• Author & Contributor: Rimguy
• Author & Contributor: WHULorigan
• Author & Contributor: Lord (Marquis) and Master of Sophontology Maksim-Smelchak of the Ministry of Science