Astral projection

Astral projection was a rare Force power, which enabled the user to see events outside of their "sphere of influence".

A user of astral projection would lie still and let something--which looked like holovids of a person's departing spirit--out, and that something could roam the galaxy, looking for the user's intended target. The only people who could sense the presence of astral projection were fellow force-sensitives.

Several "prophets" of the combined races, Korribanite, Massassi, and Original Sith, could utilize this Force power, which is how they knew outside events.

This power is considered to be dangerous, because the user is rendered helpless when it is in use, and even if they could respond, it would take awhile for them to "return to normal". So most Jedi, Sith, and Dark Jedi do not use or know of this strange ability.