Messier 79 (NGC 1904) - wonderfuluniverse.de

Messier 79 (NGC 1904) – VdS Remote Hakos

As a member of the VdS remote observatory group, I have the opportunity to use the VdS Remote Observatory in Hakos, Namibia. Members may process both their own data and the datasets recorded by other users. For this result, I worked with the 2024 dataset acquired by Yves Bastian, taken with the VdS instruments in Hakos.

Before that, however, I had already processed a 2023 Telescope Live dataset from Chile, obtained with a larger telescope and significantly longer total exposure time. Thanks to the superior southern sky conditions, increased aperture, and deeper integration, the Chilean data provided a more detailed and higher-quality view of the cluster. Nevertheless, the VdS dataset offered an excellent opportunity to work with material recorded within our own group and to compare results from different instruments and observing sites.

Data calibration, registration, and final processing for this project were all done with PixInsight.

The image shows the globular star cluster Messier 79, located in the faint northern part of the constellation Lepus. Situated at a distance of roughly 42,000 light-years, M79 lies far below the Galactic plane and is one of the few bright globular clusters visible in the winter sky of the Northern Hemisphere. With an estimated age of about 11 billion years, it is composed almost entirely of old, metal-poor stars that formed early in the history of the Milky Way.

What makes Messier 79 particularly interesting is its possible extragalactic origin. Several studies suggest that M79 may belong to the tidal debris stream of the Canis Major dwarf galaxy, a small stellar system thought to be in the process of merging with the Milky Way. If this scenario is correct, M79 would not be a native Milky Way globular cluster but an accreted intruder, captured during the Galaxy’s long history of interacting with smaller satellites.

M79 has a compact, concentrated core characteristic of many old globulars, containing numerous horizontal branch stars and several known variables, including RR Lyrae stars that serve as distance indicators. Deep imaging can also reveal faint outer halo stars and subtle asymmetries that may relate to the cluster’s past gravitational encounters.