The great distance (20,000 light-years) and intervening dust mean that the star is not usually visible to the naked eye; its apparent brightness varies erratically between magnitude 5.7 and 9.0.

[4][6] Parallaxes from data release 1 (DR1) of the Gaia mission suggest a much closer distance to AG Carinae and its neighbour Hen 3-519 than previously accepted, around 2,000 parsecs.

Then both stars would be less luminous than LBVs and it is argued that they would be former red supergiants whose unusual characteristics are the result of binary evolution.

[17] The distance of 6,000 parsecs is based on assumptions about the properties of LBVs, models of interstellar extinction, and kinematical measurements.

[18] A 2017 study argues that the 0.3 mas systematic margin of error can be ignored and that the implied distance to AG Carinae is 2.50±1.41 kpc.