GeminiFocus April 2015 | Page 10

Nancy A. Levenson Figure 1. The outflow of the “Orion Fingers” is evident in this highresolution image. The leading fingertips appear in [Fe II] (cyan), and the trailing fingers are evident in molecular hydrogen emission (orange). Comparison with earlier observations shows the motion and morphological changes of the emitting knots. Science Highlights Data from instruments on both Gemini North and South have boosted our understanding of the structure and kinematics of hypersonic bullets in the Orion Molecular Cloud region, led to a significant colormagnitude diagram of a cannibalized extragalactic globular cluster, and confirmed the existence of a 12 billion solar mass black hole in a quasar that formed only about 875 million years after the Big Bang. New Clarity and Change in an Explosive Stellar Outflow The outflow that emerges from the Orion Molecular Cloud 1 (OMC1) offers a rare opportunity to observe a catastrophic episode in a massive star-forming region. The outflow’s large scale, and the common dynamical age of its many high-velocity knots (in the region known as the “Orion Fingers”), point to an explosive origin. New observations using the Gemini Multi-Conjugate Adaptive Optics System (GeMS), and the Gemini South Adaptive Optics Imager (GSAOI), provide the sharpest views ever obtained of the large region, nearly reaching the diffraction limit with a resolution of 0.08 to 0.1 arcsecond. The new narrow-band images show [Fe II] emission at the fingertips, where the material is ionized and excited at the leading shock fronts (Figure 1). Additional shocks excite molecular hydrogen in the wakes of the trailing regions. John Bally (University of Colorado) and collaborators directly measure the motion of specific fingers in the outflow and their morphological changes. They also compare the current data with earlier observations, especially those obtained using adaptive optics (Altair/NIRI) at Gemini North. They find proper motions up to 300 kilometers per second (km/s). 8 GeminiFocus April 2015