SSI Data File Summary
The TSIS-1 SIM Solar Spectral Irradiance (SSI) data product is constructed using measurements from the SIM instruments, which are combined into merged daily solar spectra over the spectral intervals shown in the table below. The TSIS SSI data products are provided on a fixed wavelength scale, which varies in spectral resolution from 1–34 nm over the entire spectral range. Irradiances are reported at a mean solar distance of 1 AU and zero relative line-of-sight velocity with respect to the Sun. Learn more about TSIS-1 SSI data products.
| Measuring Instrument | SIM |
| Temporal Cadence | Daily, 12-Hourly |
| Detector | Photodiodes, ESR |
| Spectral Range | 200 – 2400 nm |
| Spectral Res. | 1 – 34 nm |
| Accuracy | 2% |
| Long-Term Repeatability | < 0.1%/yr |
| Data Level | 3 |