Summary
The local cache combines three NASA CDAWeb/HAPI MMS4 burst snippets instead of a single quiet 15-second snippet. This keeps the app static and small while giving the Learn UI quiet, Kp storm-level, and Dst storm-level examples.
Key Facts
- Quiet baseline: `2015-12-06T00:23:05Z` to `2015-12-06T00:23:20Z`, 500 rows, Kp 2, Dst -18 nT.
- Kp storm-level snippet: `2019-10-25T05:56:44Z` to `2019-10-25T05:56:45Z`, 33 rows, Kp 5, Dst -40 nT.
- Dst storm-level snippet: `2025-10-30T16:31:02Z` to `2025-10-30T16:31:03Z`, 33 rows, Kp 4, Dst -65 nT.
- Total cached rows: 566.
- The selected HAPI parameters are requested in metadata order.
Applied in the Build
The cache is a curated set of burst snippets, not a continuous 2015-2025 timeline. `DataUtils` marks segment boundaries when adjacent rows are separated by more than one second, and the Three.js path renders separate segment trails rather than drawing one continuous line between snippets.
The educational copy can demonstrate both Kp 5 storm-level activity and Dst -65 nT storm-level activity without making a live API request.
Citation
Primary source: https://cdaweb.gsfc.nasa.gov/hapi/data?id=MMS4_MEC_BRST_L2_EPHT89D
Build note: `mms4/research/mms-curated-storm-burst-cache.md`