HD 160529

HD 160529 (V905 Scorpii) is a luminous blue variable (LBV) star located in the constellation of Scorpius. With an apparent magnitude of around +6.8 cannot be seen with the naked eye except under very favourable conditions, but it is easy to see with binoculars or amateur telescopes.

Physical characteristics
V905 Sco has a peculiar variable spectral type with emission lines and P Cygni profiles. At visual maximum it is similar to an A9 star and at minimum close to B8. The distance has been estimated at 2.5 kiloparsecs (8,200 light years) based on the assumption of an absolute magnitude of −8.9. However this distance is uncertain and values between 1.9 kiloparsecs and 3.5 kiloparsecs have been proposed.

Working with a distance of 2.5 kiloparsecs, the radius varies from when quiescent to  in outburst. The temperature also varies, from 8,000K in outburst to 12,000K when quiescent. With these parameters, the apparent visual magnitude varies by 0.5 and the bolometric luminosity is constant at.

Estimates of the surface gravity lead to a mass of and a probable initial mass of   This suggests that V905 Sco is a former red supergiant star.