The Nuclear Spectroscopic Telescope Array (NuSTAR) mission, launched on 2012 June 13, is the first focusing high-energy X-ray telescope in orbit. NuSTAR operates in the band from 3 to 79 keV, extending the sensitivity of focusing instruments far beyond the ~10 keV high-energy cutoff achieved by all previous X-ray satellites. The inherently low background associated with concentrating the X-ray light enables NuSTAR to probe the hard X-ray sky with a more than 100-fold improvement in sensitivity over the collimated or coded mask instruments that have operated in this bandpass. The observatory was placed into a 600-km altitude, 6 degree inclination circular orbit, and consists of two co-aligned grazing-incidence X-ray telescopes pointed at celestial targets by a three-axis stabilized spacecraft. NuSTAR has completed its two-year primary science mission, and, with an expected orbit lifetime of more than 10 years, the opportunity for proposing observations as part of the General Observer (GO) program is now available, with observations beginning in 2015. Using its unprecedented combination of sensitivity and spatial and spectral resolution, NuSTAR offers opportunities for a broad range of science investigations, ranging from probing cosmic ray origins to studying the extreme physics around compact objects to mapping micro-flares on the surface of the Sun. NuSTAR also responds to targets of opportunity including supernovae and gamma-ray bursts. This table contains a list of (a) unobserved targets that are planned or have been accepted for observation by NuSTAR in the future and (b) NuSTAR observations which have been processed and successfully validated by the NuSTAR Science Operation Center. The data from these observations may or may not be public and the user should check the value of the public_date parameter to determine the status of a specified data set. Only those ObsIDs which have a public_date in the past will have data publicly available. Observations with a public_date parameter value which is either blank or a date in the future have been ingested into the HEASARC archive but will remain encrypted until their public date. Entries with the status field set to 'accepted' are targets approved for scheduling, and the planned exposure time given in the exposure_a (and exposure_b) parameter will have a negative value for those targets. This database table is based on information supplied by the NuSTAR Project at Caltech. It is automatically updated on a regular basis. This is a service provided by NASA HEASARC .
