The RenderableStars class requires a few different data variables in the SPECK file. The mapping between the internal name and the name of the variable in the SPECK file can be specified in the .asset file. The combination of selected rendering parameter determines which values are necessary:

Size Composition	Color Option	Required Data Value
App Brightness	Color	luminance
Lum and Size	Color	bv, luminance, absoluteMagnitude
Lum, Size and App Brightness	Color	bv, luminance, absoluteMagnitude
Abs Magnitude	Color	bv, absoluteMagnitude
App Magnitude	Color	bv, absoluteMagnitude
Distance Modulus	Color	bv, absoluteMagnitude
App Brightness	Velocity	luminance, vx, vy, vz
Lum and Size	Velocity	luminance, absoluteMagnitude, vx, vy, vz
Lum, Size and App Brightness	Velocity	bv, luminance, absoluteMagnitude, vx, vy, vz
Abs Magnitude	Velocity	absoluteMagnitude, vx, vy, vz
App Magnitude	Velocity	absoluteMagnitude, vx, vy, vz
Distance Modulus	Velocity	absoluteMagnitude, vx, vy, vz
App Brightness	Speed	luminance, speed
Lum and Size	Speed	luminance, absoluteMagnitude, speed
Lum, Size and App Brightness	Speed	bv, luminance, absoluteMagnitude, speed
Abs Magnitude	Speed	absoluteMagnitude, speed
App Magnitude	Speed	absoluteMagnitude, speed
Distance Modulus	Speed	absoluteMagnitude, speed
App Brightness	Other Data	luminance,
Lum and Size	Other Data	luminance, absoluteMagnitude,
Lum, Size and App Brightness	Other Data	bv, luminance, absoluteMagnitude,
Abs Magnitude	Other Data	absoluteMagnitude,
App Magnitude	Other Data	absoluteMagnitude,
Distance Modulus	Other Data	absoluteMagnitude,
App Brightness	Fixed Color	luminance
Lum and Size	Fixed Color	luminance, absoluteMagnitude
Lum, Size and App Brightness	Fixed Color	bv, luminance, absoluteMagnitude
Abs Magnitude	Fixed Color	absoluteMagnitude
App Magnitude	Fixed Color	absoluteMagnitude
Distance Modulus	Fixed Color	absoluteMagnitude

The bold values denote the default value for the stars.asset distributed with OpenSpace