THEMIS-A: Spacecraft Plasma Moments from ESA and SST Instruments

THEMIS-A satellite data provides spin-resolution plasma moments for both ions and electrons, corrected for spacecraft charging. On-board calculations include number density, particle flux, and momentum flux, with ground processing adding velocity, pressure, and temperature in multiple coordinate systems. This dataset is produced by the National Aeronautics and Space Administration and was last updated in March 2026.

Use Cases

• Modeling magnetospheric plasma dynamics based on ion and electron density and velocity measurements.
• Analyzing solar wind interaction with Earth's magnetic field based on pressure and temperature tensors.
• Studying spacecraft charging effects in space plasmas based on the described energy correction method.
• Comparing plasma behavior in different coordinate systems (DSL, GSE, GSM, MFA) based on the calculated velocity data.

Strengths

• Data includes corrections for spacecraft charging using spacecraft potential measurements.
• Moments are calculated for both ions and electrons from two instrument sources (ESA and SST).
• Velocity is provided in four distinct coordinate systems (DSL, GSE, GSM, MFA).

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count is unknown, which may limit suitability assessment.
• Description metadata is limited; actual data quality requires manual inspection after download.

Provenance

Source

National Aeronautics and Space Administration

Collection Method

Data collected by the THEMIS-A spacecraft's ESA (Electrostatic Analyzer) and SST (Solid State Telescope) instruments, with on-board and ground-based moment calculations.

Freshness

Last updated 2026-03-13 10:50:36.181077; freshness should be verified.

Geography

Space-based measurements from the THEMIS-A satellite orbit.