An interesting incident in the life of Ramana will explain about OOBE.
'Vasishtha Ganapathi muni' proclaimed Ramana of Thiruvannamalai, India,as "Maharishi' meaning 'Great Sage' to the whole world.
Once 'Ganapathi muni' went to Thiruvotriur , now a part of Chennai, India. He started doing penance in the Ganehsa Temple. On the eighteenth day a strange thing happened. The Muni was wide awake, sitting and meditating. He suddenly saw Ramana there. Surprised he got up hurriedly with devotion welling up in his heart; but Ramana put his hand on the Muni's head and made him sit down. The Muni was surprised and thrilled because the whole world knows that Ramana has never moved out of Thiruvannamalai.
When Ramana touched the Muni, a great Force cascaded through his frame. Billows of sheer joy rose from his heart and overflowed. At the same time, what happened to Ramana in Thiruvannamalai, he himself narrated later on in the course of conversation.
At that time, Ramana was as usual sitting in a cave on the hill of Thiruvannamalai.He experienced that from his heart a ray of light rose and darted through his head outside. Along with it Ramana went up the sky traveling on the path of the luminaries. He heard some-where the word Thiruvotriyur and came down. He walked up the road in front of him, saw the Ganesha Temple and entered it.
He spoke to Ganapathi Muni and touched him.
ESP Projection, 'astral projection', 'out of body experience' are nearly, if not entirely, synonymous terms.
A study of ESP projection was reported by Homell Hart (1954), the chairman of a committee appointed for the purpose at an international congress in Europe. Hart defined a 'full-fledged' projection ideally as a situation in which a 'projected' individual carries within himself 'full memories and purposes' during his projection out of his body and afterwards.
Robert Crookall devoted nine volumes to out of body experiences. South African investigator J.CPoynton has collected 122 cases. English researcher Celia Green has brought 326 cases.
Astral body can be explained as an exact replica of the physical body but composed of finer matter.
Coming back to Ramana's incident, Ramana exclaimed that he understood the way the Siddhas (meaning perfect souls or sages) travel in the air from place to place.
The OOBE experience is a step in Yoga siddhi (meaning one of the benefits of Yoga).
One who understands yoga and practice it could very easily understand OOBE.