H II region: Quick Facts

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Facts

Also Known As	ionized hydrogen cloud • diffuse nebula • HII region

Photos

Orion Nebula (M42)

star-forming region in the Orion Nebula

A plume of gas (lower right) in the Orion Nebula.This highly supersonic shock wave—moving at a speed of more than 238,000 km (148,000 miles) per hour—was produced by a beam of material emanating from a newly formed star.

Lagoon Nebula (M8, NGC 6523) in the constellation Sagittarius.This bright diffuse nebula is so large that light from the stars involved does not penetrate its boundaries, and the bright nebula appears to be seen against a larger, darker one.

The inner part of the 30 Doradus Nebula, the most luminous nebula in the entire Local Group of galaxies. It is located in the Large Magellanic Cloud.

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Topics

ultracompact H II region supergiant nebula Strömgren sphere Radio source Quasar Molecular cloud pulsar Hydrogen cloud Radio jet

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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