The Near-Infrared Spectrograph (NIRSpec) is a near infrared multi-object dispersive spectrograph capable of simultaneously observing more than 100 sources over a field-of-view (FOV) larger than 3' x 3'. The NIRSpec will be the first spectrograph in space that has this capability. Targets in the Field of View are normally selected by opening groups of shutters in a micro-shutter array (MSA) to form multiple apertures. The microshutters are arranged in a waffle-like grid that contains more than 62000 shutters with each cell measuring 100 µm x 200 µm. Sweeping a magnet across the surface of the MSA opens all operable shutters. Individual shutters may then be addressed and closed electronically. NIRSpec is also capable of Fixed-slit and Integral-field spectroscopy and provides medium-resolution spectroscopy over a wavelength range of 1 - 5 µm and lower-resolution spectroscopy from 0.6 - 5 µm.
NIRSpec will address all of the four main JWST science themes, and much more. It will enable large spectroscopic surveys of faint galaxies at high redshift, obtain sensitive spectra of transiting exoplanets and image line emission from protoplanetary disks and protostars. NIRSpec is being built for the European Space Agency (ESA) by the Astrium consortium with Dr. Pierre Ferruit guiding its development as the ESA JWST Project Scientist. Peter Jakobsen, the NIRSpec Instrument PI, retired in December 2011.
STScI NIRSpec team members Diane Karakla and Karrie Gilbert presented NIRSpec development work at the IAU General Assembly meeting in Honolulu in August.
The NIRSpec instrument is getting prepared for the ISIM Cryo-vac 3 testing at Goddard, scheduled to begin in October.
NIRSpec now has its flight detectors installed, as well as new Micro-Shutter Arrays. In both cases the new devices are better than the previous items. These new devices will be tested later this year during the Cryo-Vac 3 (CV3) test at Goddard. Due to a series of mishaps, NIRSpec had a failure of one electronics board in the Micro-shutter Control Electronics (MCE). That board is being prefabricated and should be available in late April. Meanwhile, NIRCam has been replaced in ISIM and NIRSpec is to follow soon.
At STScI we are working on the ground systems that are needed to plan observations, turn those into spacecraft commands, provide the data reduction and archiving pipelines. We are also preparing to support proposers and users and to calibrate all the instruments.