When to Use the Stellar Spectral Classification 3D Explorer
Open the Stellar Spectral Classification 3D Explorer when you want a hands-on answer to why stars are sorted into OBAFGKM letters, which absorption lines dominate at a given temperature, or how a giant differs in size from a dwarf at the same class.
Sessions this explorer fits
Students learning the Morgan-Keenan classification system for the first time, anyone who wants to see why Balmer lines peak at A-type instead of the hottest stars, and readers comparing a real giant (Aldebaran) or supergiant (Betelgeuse) against a main-sequence dwarf all get a direct, hands-on answer here.
Sessions this explorer does not fit
Sessions this page does not fit are learning the continuous Wien-peak color-temperature curve with no line spectrum, which is on the Black-Body Radiation 3D Explorer; or plotting many stars at once by temperature and luminosity, which is on the HR Diagram 3D Explorer. Walk through the controls in the step-by-step guide.
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