First Science Observations with SOFIA/FORCAST: 6 TO 37 micron Imaging of Orion BN/KL

TL;DR

This paper presents new high-resolution infrared images of the Orion BN/KL region using SOFIA/FORCAST, revealing the dominant sources of emission at various wavelengths and identifying a new emission source related to protostellar activity.

Contribution

First high-resolution 6-37 micron imaging of Orion BN/KL with SOFIA/FORCAST, revealing the true brightness sources and a new emission feature in the region.

Findings

IRc4 is brighter than BN at >31.5 microns.

IRc4 is likely self-luminous based on temperature maps.

A new emission source coincides with the outflow from radio source I.

Abstract

The BN/KL region of the Orion Nebula is the nearest region of high mass star formation in our galaxy. As such, it has been the subject of intense investigation at a variety of wavelengths, which have revealed it to be brightest in the infrared to sub-mm wavelength regime. Using the newly commissioned SOFIA airborne telescope and its 5-40 micron camera FORCAST, images of the entire BN/KL complex have been acquired. The 31.5 and 37.1 micron images represent the highest resolution observations (<=4") ever obtained of this region at these wavelengths. These observations reveal that the BN object is not the dominant brightness source in the complex at wavelengths >31.5 microns, and that this distinction goes instead to the source IRc4. It was determined from these images and derived dust color temperature maps that IRc4 is also likely to be self-luminous. A new source of emission has also been identified at wavelengths >31.5 microns that coincides with the northeastern outflow lobe from the protostellar disk associated with radio source I.