Sh 2-308
H II region in the constellation Canis Major
Sh 2-308, also designated as Sharpless 308, RCW 11, or LBN 1052, and commonly known as the Dolphin-Head Nebula, is an H II region located near the center of the constellation Canis Major, composed of ionised hydrogen. It is about 8 degrees south of Sirius, the brightest star in the night sky. The nebula is bubble-like and surrounds a Wolf–Rayet star named EZ Canis Majoris. This star is in the brief, pre-supernova phase of its stellar evolution. The nebula is about 4,530 light-years (1,389 parsecs) away from Earth, but some sources indicate that both the star and the nebula are up to 5,870 ly (1,800 pc) away. Yet others indicate the nebula is as close as 1,875 ly (575 pc) from Earth.
Central star
Sh 2-308 surrounds the Wolf–Rayet star EZ Canis Majoris, also designated EZ CMa or WR 6. Its apparent magnitude varies from 6.71 to 6.95. Its spectral type indicates that the star is very hot and luminous. The spectrum shows that it is devoid of hydrogen at the surface.
Begin with the source’s own compact description: “Sh 2-308” is h II region in the constellation Canis Major. The dossier treats that line as a proposition to test through 2-308, region and constellation, not as a finished interpretation.
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Named sources, stable identifiers and responsible institutions provide the strongest route from overview to verifiable evidence. The source revision retrieved here is dated Aug 23, 2026. The linked authority identifier is Q30086636. None of the 0 selected statements returned an explicit reference. The first chronological checks are 1052.
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This entry incorporates text from “Sh 2-308” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.