The Starfleet Science Center was a Federation Starfleet outpost facility located on the planet Rifton in the 23rd century. In the late 2260s, its commanding officer was Vice Admiral Julianna van Leeuwenhook.
In 2269, Starfleet Science Center researchers recognized that seemingly infrequent starship disappearances in the Cicada sector occurred precisely 27.344 star years apart, with the next predicted event to occur imminently. Van Leeuwenhook sent the USS Enterprise to investigate, as the disappearances included Klingon, Romulan and Federation vessels. (TOS - Log Two novelization: The Lorelei Signal)