James Webb Space Telescope Feed Post

Arxiv: A JWST survey of the Trapezium Cluster & inner Orion Nebula. I. Observations & overview Published: 10/5/2023 5:05:18 PM Updated: 10/5/2023 5:05:18 PM

Paper abstract: We present a near-IR survey of the Trapezium Cluster and inner Orion Nebulausing the NASA/ESA/CSA James Webb Space Telescope. The survey with the NIRCaminstrument covers 10.9 x 7.5 arcminutes (~1.25 x 0.85 pc) in twelve wide-,medium-, and narrow-band filters from 1-5 microns and is diffraction-limited atall wavelengths, providing a maximum spatial resolution of 0.063 arcsec at 2microns, corresponding to ~25 au at Orion. The suite of filters chosen wasdesigned to address a number of scientific questions including the form of theextreme low-mass end of the IMF into the planetary-mass range to 1 Jupiter massand below; the nature of ionised and non-ionised circumstellar disks andassociated proplyds in the near-IR with a similar resolution to prior HSTstudies; to examine the large fragmented outflow from the embedded BN-KL regionat very high resolution and fidelity; and to search for new jets and outflowsfrom young stars in the Trapezium Cluster and the Orion Molecular Cloud 1behind. In this paper, we present a description of the design of theobservational programme, explaining the rationale for the filter set chosen andthe telescope and detector modes used to make the survey; the reduction of thedata using the JWST pipeline and other tools; the creation of large colourmosaics covering the region; and an overview of the discoveries made in thecolour images and in the individual filter mosaics. Highlights include thediscovery of large numbers of free-floating planetary-mass candidates as low as0.6 Jupiter masses, a significant fraction of which are in wide binaries; newemission phenomena associated with the explosive outflow from the BN-KL region;and a mysterious "dark absorber" associated with a number of disparate featuresin the region, but which is seen exclusively in the F115W filter. Furtherpapers will examine those discoveries and others in more detail.