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How to explore HR Diagram 3D Explorer

Open the HR Diagram 3D Explorer, highlight each stellar locus, and read the Sun at Teff ~5,772 K and L = 1 Lsun on the schematic axes.

Open https://freetoolonline.com/space-3d/hr-diagram.html and wait for the temperature / log(L/Lsun) axes and colored point clouds.
Read the facts panel: Sun Teff ~5,772 K, main sequence, giants, white dwarfs, luminosity and temperature.
Press Main sequence to highlight the O/B through M dwarf band along the diagonal locus.
Press Giants or White dwarfs to focus high-L giants or hot faint white-dwarf regions.
Press Sun for the G-type anchor; scrub Spectral class O-M or Facts table for the teaching summary.

Next: the when guide or vs alternatives. Open the HR Diagram 3D Explorer.

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Last updated: Jul 15, 2026

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