Stars

Star navigation models render the predicted appearance of catalog stars in the field of view and emit one NavFeature per surviving star. All concrete subclasses derive from NavModel directly; the shared catalog reduction, conflict marking, and photometry helpers live in the nav.nav_model.stars subpackage.

Registered concrete subclasses:

• NavModelStars — catalog-driven star navigation; one instance per observation. Documented at Star Navigation Model.

• NavModelStarsSimulated — reserved without an implementation. The simulated-image GUI variant would render stars from operator-supplied parameters. Documented at Simulated Star Navigation Model.

The nav.nav_model.stars subpackage carries the catalog reduction (catalog.py), per-star body / ring conflict marking (conflicts.py), the raw-DN photometry diagnostic and B-V colour mapping (predicted_snr.py), and smear-aware PSF construction (smeared_psf.py). Each helper is independently testable so the per-step assumptions can be exercised in isolation.

• Star Navigation Model
  • Overview
  • Theory
    • Catalog reduction
    • Conflict marking
    • Magnitude detectability gate
    • Magnitude-margin effective SNR
    • Per-feature uncertainty
    • Restrictions and assumptions
    • Sources of uncertainty
  • Configuration
    • Module-level emission constants
    • Per-instrument overrides
  • Implementation
    • Annotation helpers
    • Per-image metadata
    • Call path
  • Examples
• Simulated Star Navigation Model
  • Overview
  • Theory
    • Restrictions and assumptions
    • Sources of uncertainty
  • Configuration
  • Implementation
  • Examples