Stellar classification: Quick Facts

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A Hertzsprung-Russell diagram plotting stars by absolute magnitude and spectral type, showing regions for main sequence stars, white dwarfs, giants, and supergiants, with color gradients from blue (hot and bright) to red (cool and dim). The Sun is marked along the main sequence.

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Topics

Why are stars different colors?spectral type Hertzsprung-Russell diagram Wolf-Rayet star

Key People

Cecilia Payne-Gaposchkin

Cecilia Payne-Gaposchkin

British-born American astronomer

Annie Jump Cannon

Annie Jump Cannon

American astronomer

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Pietro Angelo Secchi

Italian astronomer

Nicolaus Copernicus. Nicolas Copernicus (1473-1543) Polish astronomer. In 1543 he published, forward proof of a Heliocentric (sun centered) universe. Coloured stipple engraving published London 1802. De revolutionibus orbium coelestium libri vi.

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Nicolaus Copernicus. Nicolas Copernicus (1473-1543) Polish astronomer. In 1543 he published, forward proof of a Heliocentric (sun centered) universe. Coloured stipple engraving published London 1802. De revolutionibus orbium coelestium libri vi.

All About Astronomy

1 July 2002: The Solar and Heliospheric Observatory (SOHO) satellite reveals a massive solar eruption more than 30 times the Earth's diameter. The eruption formed when a loop of a magnetic field over the surface of the Sun trapped hot gas.

Brightest Star in the Solar System