Palomar 5Also identified as Pal5, it is a globular cluster and a member of the Palomar Globular Clusters (see paragraph below). It was discovered by Walter Baade in 1950, and independently found again by Albert George Wilson in 1955. After the initial name of Serpens Dwarf (I suspect it was initially thought to be a dwarf galaxy), it was subsequently catalogued as Palomar 5.
The cluster is currently 60.6 kly from the Galactic Center, in line with the galactic center, 45 degrees above the galactic plane. It shows a noticeable amount of flattening, with an aspect ratio of 0.62 (ar = semiminor axis/semimajor axis).
It is visually very close to the celebrity M5, which, being much closer, at 24.5 kly, is nearly on the vertical of the galactic center.
The Pal5 Stellar StreamThere is a process of disruption acting on this cluster because of the gravitation of the Milky Way – in fact there are many stars leaving this cluster in the form of a stellar stream. The stream has a mass of 5000 solar masses and is 30,000 light years long. The Pal5 Stellar Stream is one of the few ones strongly attributable to a well defined progenitor. The stream has been recently used to determine the enclosed mass of milky way, and, more in general, is a trove of precious information.
Here is a nice 2019 article by Adrian M. Price-Whelan et Alii, about the Pal5 stellar stream.
Palomar Globular ClustersThe Palomar GCs are some of the faintest of all globular clusters in the Milky Way, and been discovered in the 1950s on the survey plates of the first Palomar Observatory Sky Survey (POSS). In total there are 15 Palomar GCs, of which 13 had been never seen before.
Some of the astronomers who identified these objects as globular clusters include prestigious names as George Abell, Fritz Zwicky, Edwin Hubble, Halton Arp and Walter Baade.
Picture: The Pal 5 Stellar stream. Credit Adrian M. Price-Whelan et Alii, 2019, quoted article in text. 
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