High Resolution Mapping of the Orion Nebula Region at 30, 50 and 100 Microns
The central ~4’ x 4’ region of the Orion Nebula-OMC1 complex has been mapped with 20” resolution in well-defined bands at 30, 50, and 100 µ from the NASA C-141 infrared observatory. These data provide detailed information about the distribution of matter, luminosity, and temperature in this region. The principal results are the following: A) At all three wavelengths, the surface brightness peaks sharply at the position of the infrared cluster, which includes the Becklin-Neugebauer and Kleinmann-Low objects, to the northwest of the Trapezium. The total 25 to 130 µ luminosity from a 30” region centered on this peak is 4 x 104 LO. B) This emission peak is resolved spatially at all three wavelengths, with a characteristic half-width of 35”. C) The color temperature of the emission at the peak is ~120 K. The temperature decreases uniformly away from this peak as expected for a dust cloud heated by a central luminosity source. D) At all three wavelengths, the surface brightness of the emission in the direction of the H II region is measured to be less than 10% of the peak surface brightness. The color temperature of this emission is ≤ 200 K. E) At 50 µ and 100 µ, there is a strong suggestion of a ring of emission surrounding the H II region, which is well-correlated with the position of optically visible ionization fronts. F) The previously identified bar of emission associated with the ionization front near θ2A Orionis is not resolved at any wavelength and is smaller than 30’ in NW-SE extent. G) The total 25–130 µ emission from the region mapped is ~ 2 x 10 LO, The infrared cluster and the Trapezium cluster appear to make roughly equal contribution to this luminosity.