M78, McNeil's Nebula, v1647Ori what do these things have in common?

M78, McNeil's Nebula and v1647Ori
©Billy Vazquez, 2011 @ VAO Webster, NY

They are all part of the Orion Molecular Cloud Complex.  They are also part of these image taken from VAO a few nights ago.  M78 on the upper left corner of these image is an HII region and it the brightest and most prominent object of this field but regardless there are several other nebula like objects, for example McNeil's Nebula.   

McNeil's Nebula has a very interesting story behind it.   Discovered by McNeil in 2003 after having done an exhaustive search on this field at different epochs.  But was it really a new object in the sky?  Apparently as close to the mid 1960s and by no other than an amateur astronomer(Evered Kramer).  There is clear evidence that the nebula was visible then.   So how come it disappeared just to reappear again for McNeil to find?  This is still the topic of active research.   The prevalent explanation is that the young star v1647Ori has episodic outburst whose light reflects and scatters by the dust in McNeil's Nebula.

These outbursts from young stars and their associated nebulosity are coined Herbig-Haro objects and they are like I said still the subject of astronomical research, so that we can understand the physics that powers this phenomena.