Do I need to install anything?

No. It runs in any modern browser, free, with no account required.

For Students · Star Lifecycle

Star Lifecycle for a coral colony

Built for students learning it for a class or exam. See the concept move instead of memorizing formulas — and check your homework intuition. Simulate a coral colony live below — adjust the inputs and watch it respond, right in your browser.

H-R Diagram

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Hertzsprung-Russell DiagramLive

the map of the stars

Controls

Presets

Your star temperature (K)

The H-R diagram plots stars by temperature and luminosity, revealing the main sequence (a diagonal band), red giants, supergiants, and white dwarfs. Your star (pink ring) sits on the main sequence where luminosity scales as T⁴.

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Data Inspector

Spectral classG

Luminosity1.00 L☉

Temperature5,778 K

Governing equation

\frac{L}{L _{⊙}} = (\frac{T}{T _{⊙}})^{4} = (\frac{5778}{5778})^{4} = 1.00

Reading this result: A cool orange K-type star: lower temperature places it low-right on the main sequence, dimmer and longer-lived than the Sun.

Runs locally in your browser — free forever. Scale to the cloud when reality gets heavy.

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Blackbody

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Blackbody RadiationLive

Planck's law · Wien's displacement

Controls

Every warm object glows with a Planck spectrum. Heat it up and the peak shifts to shorter (bluer) wavelengths — that's why stars range from red to blue-white.

Presets

Temperature (K)

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Data Inspector

Temperature5778 K

Peak wavelength502 nm

Colorwhite/yellow

Governing equation

λ_{m a x} = \frac{b}{T} = \frac{2.898 \times 1 0 ^{6}}{5778} = 502 nm

Reading this result: At 5778 K the Planck curve peaks at 502 nm, inside the visible band — Wien's law makes peak wavelength ∝ 1/T, so doubling the temperature halves the peak wavelength and shifts the glow toward blue.

Runs locally in your browser — free forever. Scale to the cloud when reality gets heavy.

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Frequently asked questions

Is this good for students?: Yes — this version of "Star Lifecycle for a coral colony" is framed for students learning it for a class or exam. See the concept move instead of memorizing formulas — and check your homework intuition.
Do I need to install anything?: No. It runs in any modern browser, free, with no account required.