Science mission: Bringing the high energy universe into focus
NASA’s Nuclear spectroscopic telescope Array, or NuSTAR, will allow astronomers to see a band of invisible light that has gone largely unexplored until now: the high-energy X-rays. NuSTAR will search for black holes, map supernova explosions, and study the most extreme active galaxies. "The universe is filled with light of many colors, including those we can’t see with our eyes. The colors of the rainbow are actually just a tiny slice of a vast spectrum of light that ranges from radio waves to high-energy gamma-rays." The expected mission duration is two years.
The x-ray satellite NuSTAR, launched in June 2012, is equipped with three DL400 PSDs from First Sensor. The DL400s area duolateral, two-dimensional PSDs with 400mm² active area. They are used for continuous alignment of the telescope optics with respect to the sensor unit. Optics and sensors in x-ray telescopes are separated by are large distance due to the long focal length of x-ray lenses. The 10m deployable mast in the NuSTAR satellite is characterized by low weight and low costs, yet it lacks the required buckling resistance for an optical system. Tilt and torsion of the optics with respect to the sensor are therefore monitored four times each second by three lasers. They are mounted to the optics unit and aligned to the PSDs which are placed on the sensor base. Every single DL400 detector has been measured and tested extensively by engineers of the Jet Propulsion Lab. Six out of seven components have been qualified for the highest demands of space application. A detailed description of the integration of First Sensor PSDs in the NuSTAR project can be found in the June 2012 issue of „IEEE Sensors Journal“ (Volume: 12, Issue: 6, Pages: 2006 – 2013).