ESA Science & Technology - NIRSpec calibration image, MOS-SLIT mode

This is an example of a NIRSpec calibration exposure obtained during the ISIM CV-3 test campaign.

These exposure images provide scientists with a means of accurately calibrating the instrument. In NIRSpec, light from one of the internal lamps passes through a filter selected specially for calibration. The image exhibits sharp absorption lines that can be used as references to help calibrate the wavelength response of the instrument.

NIRSpec can operate in four modes: MOS (multi-object spectroscopy), SLIT (high-contrast slit spectroscopy), IFU (integral field unit mode) and IMA (imaging mode). For this exposure, NIRSpec was operated in joint MOS-SLIT mode.