How many of us here have idea's how to put exploration in the game again, mine is about a scenario i mentioned in thread "stuff to wish for", page 2, post 11, lines 6 through 11.
An alternative way to have exploration could be they are periodical events, every so often, you could be ordered to do an autopsy or necropsy of new or known aliens, or discover a probe/shipwreck/spatial-temporal anomaly.