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Laboratory for Atmospheric and Space Physics


The primary goal of the NASA Earth Observing Systems (EOS) SOlar Radiation and Climate Experiment (SORCE) is to enable solar-terrestrial studies by providing precise daily measurements of the total solar irradiance (TSI) and the solar spectral irradiance at wavelengths extending from the ultraviolet to the near infrared. The following lists the SORCE science objectives:

  1. Make accurate measurements with high precision of total solar irradiance, connect them to previous TSI measurements, and continue this long-term climate record. Provide TSI with an accuracy of 0.01% (100 parts per million) based on SI units and with a long-term repeatability of 0.001%/yr.
  2. Make daily measurements of the solar ultraviolet irradiance from 120 to 300 nm, with a spectral resolution of 1 nm. Achieve this spectral irradiance measurement with an accuracy of better than 5%, and with a long-term repeatability of 0.5%/yr. Use the solar/stellar comparison technique to relate the solar irradiance to the ensemble average flux from a number of bright, early-type stars (same stars used by the UARS SOLSTICE program).
  3. Make the first measurements of the visible and near IR solar irradiance with sufficient precision for future climate studies. Obtain daily measurements of solar spectral irradiance between 0.3 and 2 ┬Ám with a spectral resolution of at least 1/30, an accuracy of 0.03%, and a long-term repeatability of better than 0.01%/yr.
  4. Improve the understanding of how and why solar irradiance varies, estimate past and future solar behavior, and investigate climate responses.