NuSTAR

Nuclear Spectroscopic Telescope Array ( NuSTAR ) is an orbital X-ray telescope for the observation of X-ray sources such as black holes. NuSTAR is a satellite in the NASA Explorer program. After reaching orbit NuSTAR has received the additional designation Explorer 93.

Mission

NuSTAR is an X-ray astronomy mission, in the high energy X-ray imaging with a spatial resolution of less than one minute of arc allowed for the first time. Earlier missions with Wolter telescopes such as Chandra or XMM -Newton worked up to energies of 10 keV. NuSTAR will expand the study area up to 80 keV. At these energies so far only poor spatial resolution by collimators was possible.

Other issues that should be clarified by NuSTAR, include the distribution of the black holes, the formation of heavy elements and the energy generation mechanisms of active galaxies.

NuSTAR was selected in 2005 as a SMEX ( Small Explorer ) mission, however, the development was stopped for reasons of cost in February 2006. In September 2007, NASA put the NuSTAR mission back into the budget.

NuSTAR was originally supposed to be launched in February 2012 with a Pegasus XL rocket, but the launch was shifted several times. He eventually took place on 13 June 2012. The carrier aircraft Lockheed L -1011 took off from Kwajalein Atoll, and unlatched the Pegasus XL about 193 km south of the starting location of. After that, the rocket flew into the planned orbit. The amount of NuSTARs orbit is about 600 km, the inclination of 6 °. On June 21, 2012, consisting of 56 segments of about 10 meters long mast was deployed within 26 minutes. The two Wolter telescopes at the end of the mast can now focus the X-rays on the detectors.

Construction

360 kg satellite is based on the commercial LeoStar -2 satellite structure of the company Orbital Sciences Corporation, which was already used in a similar form when Satellite GALEX. The satellite body is in the form of a hexagonal prism and has a three-axis stabilization. An adjustable boom solar cell provides power. The planned mission duration is two years.

The NuSTAR instrument consists of two aligned in the same orientation X-ray telescopes ( originally planned three). The focusing of the x-rays is accomplished by Wolter telescopes, which are mounted on an extendable, ten meters long boom. The boom allows a long focal length of the telescopes, and thus a very shallow angle of incidence of X-rays on the mirror. This can also be reflected above 10 keV X-rays. Telescopes focus the radiation on the three - cadmium zinc telluride ( CdZnTe ) detectors, which are located on the satellite body. The detectors do not require cryogenic cooling and have a high spectral resolution.

Originally (before the program was interrupted in 2006 ), however, NuStar was to be built on the basis of Spectrum Astro SA -200S satellite bus.