Pentarus II was the M-class second planet in the Pentarus system.
Pentarus II was searched by miners as a possible crash site when the shuttle Nenebek, carrying Jean-Luc Picard and Wesley Crusher, was lost in 2367. (TNG: "Final Mission")
This planet was only mentioned in dialogue.
"pen-TAR-us" was the pronunciation for Pentarus from the script pronunciation guide.