NESSI: An optimized Near-Infrared (NIR) Multi-Object Spectrograph (MOS) for Exoplanet Studies

NESSI: the New Mexico Tech Extra(solar)planet Spectroscopic Survey Instrument is a ground-based multi-object spectrograph that operates in the near-infrared and is being deployed this fall at the Magdalena Ridge Observatory 2.4 m telescope. When completed later this year, it is expected to be used to characterize the atmospheres of transiting exoplanets with unprecedented ground-based accuracies down to about K = 9 magnitude. The superior capabilities of NEESI for this type of work lay, in part, in the design philosophy used for the instrument which is well-focused on the exoplanet case. We report here on this design philosophy, detail and status of the design and assembly, and preparation for first light in the fall of 2012.