or also known as Agena. With its magnitude of 0.9, it is the 10th brightest star in the sky. Together with the star Toliman, which is only four and a half degrees away, it forms a good reference point for identifying the Southern Cross and prevents its confusion with the so-called False Cross, which is formed by the stars of the Keel and the Sail. Although this blue-white supergiant is fainter in the sky compared to Toliman, it is located about 100 times further away. Its absolute magnitude reaches -5.5. If it were located in the place of Toliman, it would have an apparent magnitude of about -10!