Overview
AEGIS is a local visualization prototype for exploring Earth observations and near-Earth object records. A persistent CesiumJS globe anchors event discovery, satellite context, and source-aware object inspection.
It is an independent project using public NASA and JPL data, not an official planetary-defense service. An open event, close approach, or catalog classification is not an emergency warning or impact prediction.
Problem
Scientific feeds differ in identity, units, timestamps, coverage, and update cadence. Combining them in one interface can create false certainty if missing enrichment, stale observations, or source failures look like complete information.
The design makes those distinctions visible while keeping the globe usable through changes in mode and source availability.
What I Built
- A persistent Cesium viewer with global navigation, local detail, bounded camera behavior, and resource cleanup.
- An Earth event index that groups NASA EONET observations, preserves source metadata, and supports Point, Polygon, MultiPolygon, and antimeridian-aware selection.
- Satellite controls separating a static global reference mosaic from optional recent observations with their own dates and coverage limits.
- Server-side JPL close-approach and Sentry adapters with NASA NeoWs enrichment, exact identity reconciliation, unit conversion, and independent source-failure handling.
- Searchable and filterable records, object details, source links, and distinct unavailable, removed, and not-active states.
- Offline synthetic acceptance fixtures that exercise real normalization and application routes without presenting fixture values as real observations.
Results and Verification
The offline acceptance run completed on November 1, 2026 UTC (October 31 in New York), with 58 unit tests, two mocked server tests, and seven application-journey groups passing. It covered event selection, satellite fallback, Near-Earth inspection, source failure and retry, direct links, empty catalogs, and repeated mode changes. The persistent viewer and measured resource counts remained stable across those cycles.
A November 1 follow-up corrected the distinction between a genuinely empty event feed and a nonempty feed with no usable observations. Its 56 in-process unit tests and four route-boundary checks passed. The earlier browser acceptance predates that repair: the real cached-loader and browser recovery path still need to be rechecked.
These are dated local verification results. They do not certify current provider availability, deployment readiness, universal device performance, or scientific prediction accuracy.
What I Learned
The interface has to preserve the meaning of its sources, not just render their coordinates. An unavailable source is different from an empty catalog, a reference image is different from a recent observation, and a persistent globe needs deliberate lifecycle management.
Limitations and Next Steps
AEGIS remains a local prototype with no public deployment linked here. Cross-instance serialized JPL access, deployment-origin acceptance, and the latest repair's full integration check remain outstanding. Additional sprints and sources are future work, not shipped capabilities.
There is no orbital simulation, impact prediction, or operational alerting. Satellite layers are visual context rather than a live video feed or analytical reflectance product.