Physical Sciences and Mathematics Commons^™

All Nirspec Needs Is Hst/Wfc3 Pre-Imaging? : The Use Of Milky Way Stars In Wfc3 Imaging To Register Nirspec Msa Observations., Benne W. Holwerda, R. J. Bouwens, M. Trenti, M. A. Kenworthy

Benne Holwerda

The James Webb Space Telescope (JWST) will be an exquisite new near-infrared observatory with imaging and multi-object spectroscopy through ESA’s NIRspec instrument with its unique Micro-Shutter Array (MSA), allowing for slits to be positioned on astronomical targets by opening specific 0′′.20′′.2-wide micro shutter doors. To ensure proper Target Acquisition (TA), the on-sky position of the MSA needs to be verified before spectroscopic observations start. An onboard centroiding program registers the position of pre-identified guide stars in a TA image, a short pre-spectroscopy exposure without dispersion (image mode) through the MSA with all shutters open. The outstanding issue is the availability …