Stellar Spectral Classification 3D Explorer vs Black-Body Radiation 3D Explorer
freetoolonline.com editorial teamBoth pages teach real star-temperature facts in one page load - 0 MB installed, USD 0, no account. The Stellar Spectral Classification 3D Explorer covers WHICH absorption-line family dominates a star's spectrum and how luminosity class changes its size; the Black-Body Radiation 3D Explorer covers the continuous Wien-peak color-temperature curve with no line spectrum and no luminosity classes.
The numbers side by side
| Aspect | Black-Body Radiation Explorer | Stellar Spectral Classification Explorer |
|---|---|---|
| Install size | 0 MB - runs in the browser | 0 MB - runs in the browser |
| Price | USD 0 | USD 0 |
| What it teaches | continuous Planck curve and Wien peak vs temperature | which absorption-line family dominates at each OBAFGKM class |
| Line spectrum shown | none - color only | 3 line-strength bars: He II, Balmer H, Ca II + metals |
| Luminosity classes | none | 3 of 5 Morgan-Keenan classes (I, III, V) with real radius examples |
Where the Black-Body Radiation Explorer wins
The Black-Body Radiation Explorer wins when the question is purely about the color-temperature relationship - the Wien displacement law and the shape of the Planck curve - with no need to think about absorption lines or star size at all.
Where the Stellar Spectral Classification Explorer wins
The Stellar Spectral Classification Explorer wins when the question is about the OBAFGKM letters themselves - why hydrogen lines peak at A-type, why a giant and a dwarf can share a temperature yet differ hugely in size - it is the only page on the site with both a line-strength model and a luminosity-class toggle.
A reasonable rule
As a reasonable rule, use the Black-Body Radiation Explorer first to build intuition for how temperature alone drives a star's color, then use the Stellar Spectral Classification Explorer to learn the letter-and-Roman-numeral system astronomers actually use to label real stars.
See how to use the Stellar Spectral Classification 3D Explorer for a step-by-step walkthrough.
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