We examine parallaxes and distances for Galactic luminous blue variables ( LBVs ) in the Gaia second data release ( DR2 ) .
The sample includes 11 LBVs and 14 LBV candidates .
For about half of the sample , DR2 distances are either similar to commonly adopted literature values , or the DR2 values have large uncertainties .
For the rest , reliable DR2 distances differ significantly from values in the literature , and in most cases the Gaia DR2 distance is smaller .
Two key results are that the S Doradus instability strip may not be as clearly defined as previously thought , and that there exists a population of LBVs at relatively low luminosities .
LBVs seem to occupy a wide swath from the end of the main sequence at the blue edge to \sim 8000 K at the red side , with a spread in luminosity reaching as low as log ( L / L _ { \odot } ) \approx 4.5 .
The lower-luminosity group corresponds to effective single-star initial masses of 10-25 M _ { \odot } , and includes objects that have been considered as confirmed LBVs .
We discuss implications for LBVs including ( 1 ) their instability and origin in binary evolution , ( 2 ) connections to some supernova ( SN ) impostors such as the class of SN 2008S-like objects , and ( 3 ) LBVs that may be progenitors of SNe with dense circumstellar material across a wide initial mass range .
Although some of the Gaia DR2 distances for LBVs have large uncertainty , this represents the most direct and consistent set of Galactic LBV distance estimates available in the literature .