After observatory activation, and a calibration and a verification phase, the first sets of NuSTAR data became publicly available on August 29th, 2013 through NASA's High Energy Astrophysics Science Archive Research Center (HEASARC), while the second NuSTAR data release took place on November 25th, 2013. NuSTAR data are most easily accessible via the usual HEASARC archive interfaces, i.e., Browse and Xamin, specifically making use of the master table of NuSTAR data sets archived at the HEASARC, the NUMASTER table. Notice that some of these data sets may not yet be public: users should check the public_date parameter in NUMASTER to determine the public availability of observations. Proprietary data are indicated by having either a null value or a future date for the public_date parameter in the NUMASTER table. Users can query this table and download the data associated with the selected observation(s) using the usual Browse/Xamin procedures.
Expert users who already know the Observation IDs (ObsIDs) of the dataset(s) in which they are interested, can also directly access NuSTAR data via the HEASARC's ftp site. The public NuSTAR data are at http://heasarc.gsfc.nasa.gov/FTP/nustar/data/obs/00/ in subdirectories 0, 1, 2, 3, etc., determined by the first digit of their ObsID: thus, the data for ObsID = 80001001002 are in the directory http://heasarc.gsfc.nasa.gov/FTP/nustar/data/obs/00/8/80001001002/.
There are some known 'issues' or unusual features for a small number of the released datasets and these are listed on the analysis page.It is expected that additional datasets will be released in late December 2013 and at roughly monthly intervals subsequently, and that by spring 2014 the HEASARC Archive will have 'caught up' with the available NuSTAR data: from then on, the data for a NuSTAR observation should become public no more than 60 days after the completion of that observation. The exceptions to this rule are:
a) Observations coordinated with another observatory which will be released at
the end of the exclusive use period associated with the other observatory,