Seventh Core Expedition/secret

The 7th core expedition would have encountered the Empress Wave. The 7th expedition, launched in 750. At that point the wave is 413 parsecs coreward of Zhodane. Since this is a well traveled route, and assuming J4 per 10 days, takes 2.8 years, places it 410 parsecs coreward of Zhodani or about Ia Sector (+12).

According to the Secret canon, this is when the Zhodani actually figure out what the Empress Wave is (in general terms) and observe its effects. It should be assumed that the 7th and 8th expeditions are to figure out what the source of the Empress Wave is.