Solar UV Spectral Radiance from SKYLAB

As part of an ongoing NASA-LWS sponsored research program, solar UV spectral radiance has been determined for the quiet sun at a variety of center-to-limb positions observed by the SO82B UV spectrograph on SKYLAB. This has been done using a high quality flatbed scanner to digitize the SKYLAB film data. The goal of the present program is to develop a spectral irradiance model that utilizes the full resolution of the SKYLAB spectra (~ 0.010 nm at 300 nm). The model requires detailed knowledge of the center-to-limb variation (CLV) at full resolution over the 200 - 400nm wavelength range. This information is also required to determine the absolute intensity calibration which uses full-disk irradiance measurements from UARS (SOLSTICE and SUSIM) in addition to the CLV. This calibration is then used to derive the disk center radiance. In addition to the quiet sun, spectra of sunspots and active regions are also being digitized and an attempt is underway to derive the CLV for these surface morphologies as well. Further, spectra at shorter wavelength (~120 - 200nm) are being examined in order to extend the wavelength coverage of these radiance and CLV results. In this presentation we will present the details of the analysis methods and results for the quiet sun. Ongoing work on sunspots and active regions will be presented as will results involving work on shorter wavelength spectra.