NGC 7380, also referred to as the Wizard Nebula, is an active star-forming complex situated approximately 7,200 light-years away in the Perseus Arm of the Milky Way, within the constellation Cepheus. This H II region, spanning roughly 110 light-years, is a prime example of an emission nebula, where intense ultraviolet radiation from newly formed, massive O-type and B-type stars ionizes the surrounding hydrogen gas, causing it to emit light.
Central to the nebula is the open star cluster, also designated as NGC 7380, which is only a few million years old. The most prominent star in the cluster, HD 240794, is an O7V star with a high effective temperature and luminosity, driving strong stellar winds that shape the surrounding nebula. These winds, along with radiation pressure, are responsible for the dynamic structures observed in the nebula, including pillars, ridges, and cavities. The "wizard-like" morphology of NGC 7380 is a result of these complex interactions between the young, massive stars and the interstellar medium (ISM).
Spectroscopic studies reveal that the nebula's emission is dominated by hydrogen-alpha (Hα) lines, with significant contributions from doubly ionized oxygen (O III) and singly ionized sulfur (S II). These emissions are crucial for mapping the physical conditions within the nebula, including electron temperature, density, and chemical abundances. NGC 7380 provides a valuable laboratory for studying the feedback effects of massive stars on their natal environments and the processes governing the lifecycle of the ISM.
Key Astrophysical Parameters:
- Distance: ~7,200 light-years
- Apparent Size: ~25 arcminutes
- Physical Size: ~110 light-years
- Spectral Types of Central Stars: O7V, B-type stars
- Dominant Emission Lines: Hα, [O III], [S II]
- Age of Star Cluster: ~4-5 million years
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