This "must see" pair in Coma Berenices is one of the highlights in the galaxy focus spring sky, especially when you have telescopes with fields larger than one degree and a suburban sky.
Johann Elert Bode discovered M 53 in 1775 and so nearly 250 years ago with a very simple Dollond telescope. Some years later, William Herschel was the first who resolved the cluster with the much larger and more powerful 18.7-inch speculum mirror telescope. Beside this detail, he discovered NGC 5053 in 1784 with the same telescope.
Beside the simple beauty of this pair, the birth of this two globular clusters are the most fascinating thing here. While we did not know about the origin of the GS's for sure in the past, GAIA changed our understanding fundamentally. Already the first released data sets in 2016 shows stellar streams around our milky way. This streams are signs of mergers and a product of former dwarf galaxies. And interestingly most of the GC's lies exactly within these streams.
Yuan et al. [2020ApJ...898L..37Y] found a relation between the newly discovered stellar stream LMS-1 (low-mass stellar-debris stream) and our OOTW objects. Naidu et al. [2020ApJ...901...48N] named this stream "Wukong". A former paper of Sang-Hyun Chun et al. [2010AJ...139...606] found a tidal bridge-like feature and an envelope structure around our two globular clusters and assumed that both interacts and M 53 has stripped stars from NGC 5053. But at least GAIA clarifies the membership of both.
I general, both GC's are metal-poor, old (~12 Gyr) and far away from us (M53 - 60kly, NGC 5053 - 57kly).
In the telescope, both shows a totally different face. While both are equally large, the Shapley–Sawyer Concentration Class of M 53 is a "V" while NGC 5053 has a "XI". In addition, M 53 has a much larger surface brightness. That makes NGC 5053 to a much more difficult partner to observe, especially when transparency is not the best. In return, NGC 5053 has an interesting background and shows some galaxies in larger apertures (Kafalis, 2002). But now it is your turn. What is the smallest aperture to catch NGC 5053 and can you see some of the background galaxies?
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