LY: Light-Years – The distance light travels in one Earth year (approx. 9.46 trillion km).

M☉: Solar Masses – A star's mass relative to our Sun's mass (1 M☉ = our Sun's mass).

R☉: Solar Radii – A star's physical size relative to our Sun's radius (1 R☉ = our Sun's radius).

L☉: Solar Luminosity – A star's true brightness relative to our Sun's brightness (1 L☉ = our Sun's brightness).

Spectral Type (OBAFGKM): A star's classification based on its temperature and color. O-type stars are hottest/bluest, M-type are coolest/reddest.