Wednesday, March 31, 2010

A View of the JWST NIRSpec Instrument

The Universe has always set the standard for colors. It produces all possible combinations of colors, granted not always in the visible light spectrum. But figuring out how these nuances intertwine is absolutely essential to, for example, determining the distance a certain object is from Earth, what chemicals it contains and so on. This is why the most impressive space observatory ever built, the James Webb Space Telescope (JWST), will feature an instrument perfectly capable of extracting this sort of data from whatever wavelengths of light enter its detectors.

The Near-Infrared Spectrograph (NIRSpec) device will be one of the most advanced spectrographs ever developed, and undoubtedly the most complex to ever fly to space. EADS/Astrium is the European Space Agency's (ESA) prime contractor for the overall NIRSpec instrument, but some of the components were constructed at the NASA Goddard Space Flight Center (GSFC), in Greenbelt, Maryland. The prototype for the actual NIRSpec instrument that will fly on the JWST recently arrived at the GSFC for preliminary testing, from its construction site in Germany.

“A spectrograph is an instrument that separates light into a spectrum. One example of a spectrograph that most folks know about is a chandelier (or diamond ring). When sunlight shines through it, it breaks it up into colors. NIRSpec analyzes those colors from deep space to help us solve mysteries,” explains GSFC expert Bernie Rauscher. He is the deputy project scientist of the telescope's Integrated Science Instrument Module (ISIM) and also the principal investigator of the NIRSpec Detector Subsystem.

This particular spectrograph will have the ability to analyze more than 100 cosmic objects at the same time, as its components were especially designed for this task. The instrument will collect readings in the infrared portion of the electromagnetic spectrum, which will enable researchers analyzing data from the instrument to determine the age, chemical composition and distances of faint galaxies. One of the primary mission goals for the James Webb Space Telescope will be to determine how galaxies began to form in the early Universe, and so this ability that the NIRSpec has will be absolutely fundamental to completing its mission.