Release Notes

v1.0.0 — Initial delivery

First release of the LEO Survivability Estimator.

Capabilities

• Survivability verdict for a propulsion failure at any chosen point in the mission (defaults to halfway).
• Survivability-window heatmap over user mass × altitude ranges, with break-even contour.
• Coast-lifetime-vs-altitude band across the mass range, with the "time still needed" reference line and minimum-safe-altitude readout.
• Sensitivity (tornado) ranking of which inputs drive the outcome, with plain-language explanations.
• Form-factor presets (1U / 3U / 6U / 12U CubeSat, ESPA-class microsat) plus fully custom ranges.
• Solar / space-weather activity selector (solar min → mean → solar max → severe storm).

Engineering

• Canonical physics in orbit-model.mjs, shared with the verifier; the live tool inlines an identical copy (drift-guarded).
• Automated verification harness (verify.mjs): 14/14 checks passing, covering density profile, lifetime regimes, monotonicity, ballistic-coefficient scaling, solar sensitivity, numerical stability, and tool/model parity.
• Zero runtime dependencies; single self-contained HTML file; all computation client-side.

Known limitations — see certification-report.md: static atmosphere with a solar multiplier (not a real space-weather time-history), drag-only near-circular decay, effective drag area supplied as an input. Screening-grade by design.