Verified answer

It's easy to leave getting back is the difficult bit.

you do it everynight when you go to sleep. For the spirit body to exit and travel it only takes seconds. The spirit or astral body can travel to different places for as long as you sleep. You'll know you've Astral projected when you wake up recalling dreams, feel exhausted on awakening, or get up with a sudden jerk, etc

There are many people who have passed on in their sleep. But since they aren't around to speak of the transition we don't know. But there are people who have had Near Death Experiences (NDE's) and Out of Body Experiences (OBEs). Google those 2 to read up on some very interesting stories.

Depends on the person and how experienced you are.

I can leave all night if I don't eat a big dinner.