TIMED SEE XPS: Modeled Solar XUV Irradiance at 0.1 nm Resolution

NASA's TIMED SEE instrument provides modeled solar extreme ultraviolet (XUV) irradiance data from 0 to 40 nm. The Level 4 data product uses CHIANTI spectral models scaled to photometer signals to generate estimates at 0.1 nm spectral resolution, with daily, orbit, and 1-minute average files available. The integrated XUV irradiance has an estimated accuracy of 30%, and the spectral distribution below 27 nm is derived from models rather than direct measurements.

Use Cases

• Modeling Earth's upper atmospheric response based on high-resolution solar XUV spectral estimates.
• Analyzing solar flare activity and temperature based on the scaling of CHIANTI isothermal flare spectra.
• Validating and calibrating other solar irradiance instruments using the modeled spectral distribution.
• Studying long-term solar variability from daily and orbit-averaged irradiance data products.

Strengths

• Provides spectral irradiance estimates at a high 0.1 nm resolution within the 0-40 nm range.
• Data products include daily, orbit (97-minute), and 1-minute average time aggregations.
• Model validation for the spectral distribution above 27 nm is performed with concurrent EGS measurements.
• Instrument degradation is monitored using redundant channels and underflight calibration rockets.

Limitations

• The spectral distribution shortward of 27 nm is from a model, not direct XPS measurements.
• Estimated accuracy for the integrated XUV irradiance is 30%, introducing uncertainty.
• Column-level documentation is absent; field semantics must be inferred after download.

Provenance

Source

National Aeronautics and Space Administration

Collection Method

Derived from TIMED SEE XPS Level 1 photometer data using CHIANTI spectral model scaling algorithms.

Time Range

Covers the TIMED mission operational period; specific start and end dates are not provided in the input.

Freshness

Last updated 2026-03-13 05:44:21.680948; freshness should be verified.

Geography

Solar observations from space; no terrestrial geographic coverage.