SWAN/SOHO: Solar Wind Anisotropy Maps from Lyman Alpha Radiation

The SWAN instrument onboard the SOHO satellite, a collaboration between the Finnish Meteorological Institute and Service d'Aeronomie, observes interplanetary Lyman alpha radiation scattered by hydrogen atoms flowing into the solar system. SWAN typically produces three full-sky radiation maps per week, capturing changes in the solar wind proton flux from solar minimum in 1996 to solar maximum. Data are available from public archives including NASA, Rutherford Appleton Laboratory, Institut d'Astrophysique Spatiale, and Osservatorio Astronomico di Torino.

Use Cases

• Modeling solar wind proton flux variations based on observed changes in the overall sky picture.
• Tracking the inflow direction of interstellar hydrogen gas based on radiation intensity peaks in sky maps.
• Analyzing temporal changes in interplanetary Lyman alpha radiation from solar minimum to solar maximum.
• Mapping the anisotropy of solar wind across the entire sky using weekly radiation observations.

Strengths

• Data originates from a dedicated instrument (SWAN) on the long-running SOHO satellite.
• Observations cover the entire sky, providing a global view of interplanetary radiation.
• The description indicates a temporal coverage spanning from solar minimum in 1996 to solar maximum.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count and file size are unknown, which may limit suitability assessment.
• Last update date is unknown; freshness unverified.

Provenance

Source

SOHO/SWAN instrument, a collaboration between Finnish Meteorological Institute and Service d'Aeronomie.

Collection Method

Satellite observations of scattered Lyman alpha radiation.

Time Range

Observations span from at least 1996 (solar minimum) to solar maximum.

Geography

Global sky coverage.