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We have combined 327.5 MHz radio observations and optical spectroscopy tostudy conditions in the Extended Orion Nebula. We see a steady progression ofcharacteristics with increasing distance from the dominant photoionizing starTheta1OriC. This progression includes a decrease in the F(Halpha)/F(Hbeta)ratio, an increase in the relative strength of scattered stellar continuum,decrease in electron density determined from the [S II] doublet, and increasein the ratio of Emission Measures derived from the Hbeta line and the 327.5 MHzradio continuum. We conclude that beyond about 5' south of Theta1OriC thatscattered light from the much brighter central Huygens region of the nebulasignificantly contaminates local emission. This strengthens earlier argumentsthat wavelength and model dependent scattering of emission line radiationimposes a fundamental limit on our ability to determine the physical conditionsand abundances in this and arguably other similar Galactic Nebulae. Theimplications for the study of extra-galactic HII regions are even more severe.We confirm the result of an earlier study that at least the eastern boundary ofthe Extended Orion Nebula is dominated by scattered light from the Huygensregion.

Scattered Nebular Light in the Extended Orion Nebula