OBE is very a common phenomenon among meditators and
non-meditators.
However it is not something we seek in Buddhist meditation, and
therefore we do not deal with this phenomenon very much. In fact we
aim to transcend our 7th consciousness rather than access and gain
control over this state.
A way to explain it in Buddhist terminology is that the astral
body is due to accessing the subtler 7th consciousness which we all
do during sleep. It is the sense of an individual self that is
present even when 6 conscious experiences subsides (five senses +
mind). We experience OBE especially when we have lucid dreams or
sleep paralysis where the 7th consciousness may experience an
astral projection or out of body experience. I had a number of
experiencs from the past. Felt like floating a feet above my body
and knowing the surroundings of my room. In fact I just got a lucid
and OBE like experience last night with seeing bright white light.
I remember I was doing some concentration or awareness exercise
within the lucid dream. I was just noting and perceiving my
auditory experience (I was hearing strange noise) to the finest
details until a flash of bright white light came. The more I
concentrated in that 'dream' the brighter the light became. The
white light came with a sense of bliss and exhilaration. I'm
guessing this might be what the Vipassana meditators called the
"Arising and Passing Away event". (A&P) which I did have
previous experiences with. I also remember having a sense of
leaving my body in that experience. But soon afterwards, I woke
up.
Anyway like I said previously we access the 7th consciousness
during sleep. It is this same 7th consciousness that experiences
the (up to) 49 days in the bardo/antarabhava state after death
waiting for opportunities for rebirth.
This also explains why some people communicate with the dead
during dream. There's a true news story from Taiwan about a family
whose grandfather got lost and died. Nobody knew where he died
until one of the family members had a dream where his grandfather
appeared and told him the location of his body and asked them to
collect his body. They went to that location, and found it.
Why is it possible? Because the bardo or antarabhava is
accessing the 7th consciousness in his afterlife experience. You
are also accessing the 7th consciousness in dream. It is the same
realm. In fact that is why Buddhist scriptures say every night we
enter the bardo and it is a similar situation at death. All 6
consciousness subsides and you enter into the 7th
consciousness.
Similarly linking back to meditation, we can access subtler
states of consciousness lucidly and therefore give rise to OBEs.
However, this is not the aim of our Buddhist meditation.
If we practice hard, we can dissolve this 7th consciousness into
an oceanic experience of our own nature, where the sense of
individuality is lost. We ultimately aim to transcend rebirth.