The Orbiting Solar Observatory-I (OSO-8) was launched on 21 June 1975 into a 550 km circular orbit at 33 degrees inclination. Data were obtained from the mission until late September 1978. The spacecraft structure consisted of a rotating cylindrical base section called the "wheel" and a non-spinning upper section called the "sail". While the primary objectives of the mission were solar in nature, there were 3 detectors, the GSFC Cosmic X-ray Spectroscopy experiments (GCXSE detectors A, B, and C), mounted in the rotating wheel which had exclusively non-solar objectives. Their fields-of-view were either aligned to the spin axis or at small angles to it, hence they always view the portion of the sky at right angles to the earth-sun line. This database accesses the pha FITS datafiles for the A, B, and C GCXSE detectors. Data was accumulated every quarter of a rotation period (~2.56 s) for the A detector and every 40.96 s for the B and C detectors in the 2-60 keV energy band. This is a service provided by NASA HEASARC .