A Gould-Belt-like structure in M 83^*

European Southern Observatory, Karl-Schwarzschild-Str. 2, 85748 Garching bei München, Germany

Corresponding author: F. Comerón, fcomeron@eso.org

Received: 17 August 2000
Accepted: 24 October 2000

Abstract

VLT archive observations of M 83 are used to study a complex in the disk of that galaxy that shows a remarkable similarity to the Gould Belt. The complex is clearly separated from the overall spiral pattern of the galaxy. It is several hundred parsecs across, and is resolved into several tens of point sources, thus looking much as the Gould Belt should if observed from above the galactic plane. The point sources are likely to be bright, Trapezium-like clusters, or compact OB associations. Many of them display Hα emission, whose luminosity is estimated to be of the order of that of the Orion nebula. The integrated absolute B magnitude of this complex and the Gould Belt are found to be comparable. The blue colors of some of the members, the abundance of Hα emission, and the lack of any apparent distortion of the shape of the complex due to galactic shear all argue for a very young age. The similarity in size, location with respect to the spiral pattern of the host galaxy, contents, age, and overall luminosity of the M 83 complex studied here strongly argue for a similarity between the two structures.