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David

Darling

Lump Star (NGC 2023)

Lump Star (NGC 2023)

The Lump Star is to the lower left of the Horsehead Nebula.


The Lump Star is the reflection nebula NGC 2023: one of the brightest sources of fluorescent molecular hydrogen in the sky. It is powered by the B star (B1.5) HD 37903, the most luminous member of a cluster of young stellar objects illuminating the front surface of the Lynds 1630 molecular cloud (Barnard 33) in Orion B (see Orion Complex). NGC 2023 forms a cavity in the surface of the cloud, some 450 parsecs from us, producing both a bright visual reflection nebula and a ultraviolet-excited photodissociation region. The Lump Star lies close by the famous Horsehead Nebula in Orion.