William Herschel once again is the discoverer on an OOTW object. But the discovery wasn't without issues. When he found this object the first time, he was sweeping through Virgo in the night from April 24 to 25, 1784, using his 18.7 inch telescope and he recorded this cluster as last of 16 new objects discovered that night. It was noted down as VI 8. However he made a mistake noting down the position and later it was noticed that that was the same position as II 190 (NGC 4928). Less than a year later, on March 5, 1785, he noted it down again as I 70, this time at the correct position.
ngc5634_panstarrs.jpg NGC 5634: Only globular cluster in Virgo. Section of PanSTARRS DR1
The cluster is the only globular cluster in Virgo and lies 1.3' west of the magnitude 7.94 K3III giant HD 127119 and has Shapley–Sawyer Concentration Class IV, making it intermediately rich in concentration towards the centre. NGC 5634 likely once was a member of the Sagittarius Dwarf Spheroid Galaxy.
So far I have only observed this globular cluster with my old 15 cm Newtonian telescope. I noted down from my observation of it on July 9, 2008, in Southern France: "Visible as a small, round glow. No bright centre but it does have faint outer regions. The centre has a uniform brightness." Apparently I wasn't able to resolve stars in it. I'll need to look this one up with my 12" and 20" telescopes.
As always,
"Give it a go and let us know!
Good luck and great viewing!"
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