[5][4] In 1994, WR 31a was first described as a candidate luminous blue variable (cLBV) after a detailed spectrographic study with the Anglo-Australian Telescope.

[7] Measurements of its parallax, published in 2017 as a result of the Gaia mission, suggested a much closer (6,500 light-year; 2,000 parsec) distance to WR 31a as well as to its neighbor, the luminous blue variable AG Carinae.

[12] However, Gaia Data Release 2 returned a parallax of 0.0418±0.0299 mas; using Bayesian inference, Smith et al. (2018) calculated its distance to be 31,200+8,500−6,000 ly (9,570+2,600−1,850 pc).

The Hubble Space Telescope (HST) has captured a striking image of the nebula, rendering it as a thin blue bubble.

These profiles may show dramatic changes on a timescale of weeks, with the absorption components of the lines sometimes disappearing completely.

[7] No significant brightness changes have been detected in WR 31a, but it has been listed as a candidate luminous blue variable because of its luminosity, temperature, and mass loss properties.