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Hertzsprung–Russell (H-R) Diagrams Documents

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Main Document

Hertzsprung–Russell (H-R) Diagrams 

written by Mario Belloni

The Hertzsprung–Russell (H-R) Diagrams model simulates Hertzsprung–Russell (HR or H-R) diagram for groups of stars. The diagram is a scatter plot of steller luminosity vs. stellar temperature. The luminosity of stars is proportional to the star's radius squared and its temperature to the fourth power, and for Main Sequence stars, their luminosity is also proportional to their mass to the 3.5 power. Since the range of stellar luminosities and stellar temperatures is so large, the plot uses a log-log scale. The diagram is a way to understand stellar evolution.

The HR diagram shows nearby stars, bright stars, and a user-defined star. One can also show the blackbody radiation curve and the user-defined star. The radius of the user-defined star (in Rsun) and the temperature of the user-defined star in Kelvin (5780 K is Tsun) can be changed.

Last Modified June 6, 2014

This file has previous versions.

Source Code Documents

Hertzsprung–Russell (H-R) Diagrams Source Code 

The source code zip archive contains an XML representation of the Hertzsprung–Russell (H-R) Diagrams Model.   Unzip this archive in your EJS workspace to compile and run this model using EJS.

Published November 11, 2010
Last Modified June 6, 2014

This file has previous versions.