# Sidereon v0.8.0 - Table of Contents

Satellite toolkit for Elixir with SGP4 propagation, coordinate transforms,
GNSS positioning, orbit determination, conjunction assessment, pass
prediction, live TLE/OMM data, real-time tracking, and a Rust NIF backend.

## Pages

- [README](readme.md)
- [Changelog](changelog.md)
- [ISS Tracker](iss_tracker.md)
- [GNSS Positioning](gnss_positioning.md)
- [Conjunction Risk Assessment](conjunction_alert.md)

- Guides
  - [Track the ISS from a Ground Station](track_iss.md)
  - [Predict Passes with Doppler](pass_prediction.md)
  - [Conjunction Screening](conjunction_screening.md)
  - [Accuracy &amp; Validation](accuracy.md)
  - [Batch Analysis: Coverage, Visibility, and Link Budgets at Scale](batch_analysis.md)
  - [GNSS Constellation Catalogs](gnss_constellation_catalog.md)

## Modules

- [Sidereon.CCSDS.CDM](Sidereon.CCSDS.CDM.md): Parse and encode CCSDS Conjunction Data Messages (CDM).
- [Sidereon.CCSDS.CDM.ObjectData](Sidereon.CCSDS.CDM.ObjectData.md): Object-specific data block inside a parsed CCSDS CDM.

- [Sidereon.Collision](Sidereon.Collision.md): Collision probability calculation for close approaches.
- [Sidereon.Collision.Result](Sidereon.Collision.Result.md): Result of a collision-probability evaluation.

- [Sidereon.Covariance](Sidereon.Covariance.md): Covariance matrix helpers for conjunction and orbit analysis.
- [Sidereon.Encounter](Sidereon.Encounter.md): Encounter geometry helpers for conjunction assessment.
- [Sidereon.Encounter.Frame](Sidereon.Encounter.Frame.md): Relative encounter geometry at a common epoch.
- [Sidereon.Forces.J2](Sidereon.Forces.J2.md): Earth's oblateness (J2) perturbation force model.

- [Sidereon.Forces.TwoBody](Sidereon.Forces.TwoBody.md): Standard Keplerian Two-Body gravity force model.

- [Sidereon.Format.OMM.Epoch](Sidereon.Format.OMM.Epoch.md): UTC calendar epoch carried by an OMM `EPOCH` field.
- [Sidereon.GNSS.Antex](Sidereon.GNSS.Antex.md): Parser and lookup helpers for ANTEX 1.4 receiver and satellite antenna blocks.
- [Sidereon.GNSS.Broadcast.ClockPolynomial](Sidereon.GNSS.Broadcast.ClockPolynomial.md): Broadcast satellite-clock polynomial.
- [Sidereon.GNSS.Broadcast.GlonassRecord](Sidereon.GNSS.Broadcast.GlonassRecord.md): One GLONASS broadcast state-vector record.
- [Sidereon.GNSS.Broadcast.IonoCorrections](Sidereon.GNSS.Broadcast.IonoCorrections.md): Broadcast ionosphere coefficients parsed from a RINEX NAV header.
- [Sidereon.GNSS.Broadcast.KeplerianElements](Sidereon.GNSS.Broadcast.KeplerianElements.md): Broadcast Keplerian orbital elements.
- [Sidereon.GNSS.Broadcast.KlobucharAlphaBeta](Sidereon.GNSS.Broadcast.KlobucharAlphaBeta.md): Klobuchar alpha and beta ionosphere coefficients.
- [Sidereon.GNSS.Broadcast.Record](Sidereon.GNSS.Broadcast.Record.md): One GPS, Galileo, or BeiDou broadcast ephemeris record from RINEX NAV.
- [Sidereon.GNSS.Broadcast.State](Sidereon.GNSS.Broadcast.State.md): A broadcast-evaluated satellite state at one epoch.
- [Sidereon.GNSS.BroadcastComparison](Sidereon.GNSS.BroadcastComparison.md): Broadcast-ephemeris accuracy: compare a broadcast navigation product against a
precise SP3 product over a window.
- [Sidereon.GNSS.BroadcastComparison.Report](Sidereon.GNSS.BroadcastComparison.Report.md): The result of a broadcast and precise product comparison.
- [Sidereon.GNSS.BroadcastComparison.Stats](Sidereon.GNSS.BroadcastComparison.Stats.md): Orbit and clock difference statistics for one satellite (or the overall set).
- [Sidereon.GNSS.Constellation.Diff](Sidereon.GNSS.Constellation.Diff.md): Change report between two GNSS constellation catalog snapshots.

- [Sidereon.GNSS.Constellation.HealthChange](Sidereon.GNSS.Constellation.HealthChange.md): A catalog/health diff observed at one snapshot epoch.

- [Sidereon.GNSS.Constellation.HealthInterval](Sidereon.GNSS.Constellation.HealthInterval.md): One half-open health interval for a satellite identity.
- [Sidereon.GNSS.Constellation.HealthTimeline](Sidereon.GNSS.Constellation.HealthTimeline.md): Health/outage timeline derived from timestamped constellation snapshots.
- [Sidereon.GNSS.Constellation.NavcenStatus](Sidereon.GNSS.Constellation.NavcenStatus.md): A parsed row from NAVCEN's GPS constellation status table.

- [Sidereon.GNSS.Constellation.Record](Sidereon.GNSS.Constellation.Record.md): A normalized GNSS satellite identity record.
- [Sidereon.GNSS.Constellation.Validation](Sidereon.GNSS.Constellation.Validation.md): Validation report for a GNSS constellation catalog.

- [Sidereon.GNSS.Ephemeris](Sidereon.GNSS.Ephemeris.md): A unified satellite-ephemeris sampling surface over precise SP3 products and
broadcast navigation messages.
- [Sidereon.GNSS.Ephemeris.Row](Sidereon.GNSS.Ephemeris.Row.md): One sampled satellite state at one epoch in the unified ephemeris table.
- [Sidereon.GNSS.PPPCorrections](Sidereon.GNSS.PPPCorrections.md): Precomputed, state-independent PPP per-range corrections for the static-arc
float/fixed solve: solid-earth tide, carrier-phase wind-up, and satellite
antenna PCO/PCV.
- [Sidereon.GNSS.Positioning.Solution](Sidereon.GNSS.Positioning.Solution.md): A single-point-positioning solution at one receive epoch.
- [Sidereon.GNSS.Positioning.SourcedSolution](Sidereon.GNSS.Positioning.SourcedSolution.md): A single-point-positioning solution paired with the provenance of the
ephemeris that produced it.
- [Sidereon.GNSS.PrecisePositioning.FixedSolution](Sidereon.GNSS.PrecisePositioning.FixedSolution.md): Static multi-epoch integer-fixed carrier-phase solution.

- [Sidereon.GNSS.PrecisePositioning.MultiEpochSolution](Sidereon.GNSS.PrecisePositioning.MultiEpochSolution.md): Static multi-epoch float-ambiguity phase positioning solution.

- [Sidereon.GNSS.PrecisePositioning.Solution](Sidereon.GNSS.PrecisePositioning.Solution.md): Float-ambiguity phase positioning solution for one epoch.

- [Sidereon.GNSS.RINEX.Clock](Sidereon.GNSS.RINEX.Clock.md): RINEX clock (`.CLK`) reader for satellite clock-bias records.
- [Sidereon.GNSS.RTK.FilterBaselineSolution](Sidereon.GNSS.RTK.FilterBaselineSolution.md): Sequential RTK baseline-filter result.

- [Sidereon.GNSS.RTK.FixedBaselineSolution](Sidereon.GNSS.RTK.FixedBaselineSolution.md): Integer-fixed RTK baseline solution from code/carrier double differences.

- [Sidereon.GNSS.RTK.FloatBaselineSolution](Sidereon.GNSS.RTK.FloatBaselineSolution.md): Float RTK baseline solution from code/carrier double differences.

- [Sidereon.GNSS.SP3.State](Sidereon.GNSS.SP3.State.md): An SP3 satellite state at one epoch.
- [Sidereon.GNSS.Staleness](Sidereon.GNSS.Staleness.md): Product-staleness graceful degradation for time-varying GNSS products.
- [Sidereon.GNSS.Staleness.IonexSelection](Sidereon.GNSS.Staleness.IonexSelection.md): A selected IONEX product paired with its staleness metadata.
- [Sidereon.GNSS.Staleness.Policy](Sidereon.GNSS.Staleness.Policy.md): Staleness cap for product selection.
- [Sidereon.GNSS.Staleness.Sp3Selection](Sidereon.GNSS.Staleness.Sp3Selection.md): A selected SP3 product paired with its staleness metadata.
- [Sidereon.GNSS.Staleness.StalenessMetadata](Sidereon.GNSS.Staleness.StalenessMetadata.md): Structured description of the product staleness behind a selection result.
- [Sidereon.Geodetic](Sidereon.Geodetic.md): WGS84 geodetic position: latitude, longitude, altitude.

- [Sidereon.LookAngle](Sidereon.LookAngle.md): Topocentric look angle from a ground station to a satellite.

- [Sidereon.Pass](Sidereon.Pass.md): A satellite pass over a ground station.

- [Sidereon.Propagator](Sidereon.Propagator.md): High-precision numerical orbit propagation.
- [Sidereon.Screening](Sidereon.Screening.md): Catalog-scale conjunction screening.
- [Sidereon.Screening.Candidate](Sidereon.Screening.Candidate.md): A prefiltered conjunction candidate from catalog screening.

- [Sidereon.Screening.Result](Sidereon.Screening.Result.md): Final result for a screened candidate pair.

- [Sidereon.TLE](Sidereon.TLE.md): Backwards-compatible delegates for TLE/OMM parsing.

- Core
  - [Sidereon](Sidereon.md): Satellite toolkit for Elixir. SGP4 orbit propagation, coordinate
transformations, and ground station pass prediction.

  - [Sidereon.Elements](Sidereon.Elements.md): Canonical representation of satellite orbital elements.
  - [Sidereon.SGP4](Sidereon.SGP4.md): SGP4/SDP4 orbit propagation from Two-Line Element sets.

  - [Sidereon.TemeState](Sidereon.TemeState.md): Represents the position and velocity of a satellite in the TEME coordinate system.

- Coordinates
  - [Sidereon.Coordinates](Sidereon.Coordinates.md): Coordinate frame transformations for satellite state vectors.

- Ground Station
  - [Sidereon.Doppler](Sidereon.Doppler.md): Doppler shift calculation for satellite-ground links.
  - [Sidereon.Passes](Sidereon.Passes.md): Satellite pass prediction over a ground station.
  - [Sidereon.RF](Sidereon.RF.md): RF link budget primitives.
  - [Sidereon.Tracker](Sidereon.Tracker.md): Real-time satellite position tracker.

- Orbit Determination
  - [Sidereon.IOD](Sidereon.IOD.md): Initial Orbit Determination methods.
  - [Sidereon.Lambert](Sidereon.Lambert.md): Lambert problem solver (Battin's method).

- Space Environment
  - [Sidereon.Angles](Sidereon.Angles.md): Angular geometry calculations for satellites.
  - [Sidereon.Atmosphere](Sidereon.Atmosphere.md): Atmospheric density via the NRLMSISE-00 empirical model.
  - [Sidereon.Eclipse](Sidereon.Eclipse.md): Earth shadow (eclipse) prediction for satellites.
  - [Sidereon.Ephemeris](Sidereon.Ephemeris.md): JPL SPK/BSP ephemeris file reader.

- Conjunction
  - [Sidereon.Conjunction](Sidereon.Conjunction.md): Find close approaches between two satellites.

- GNSS Positioning
  - [Sidereon.GNSS.Broadcast](Sidereon.GNSS.Broadcast.md): A parsed RINEX broadcast-navigation product (GPS LNAV, Galileo I/NAV+F/NAV,
BeiDou D1/D2, GLONASS).
  - [Sidereon.GNSS.CarrierPhase](Sidereon.GNSS.CarrierPhase.md): Dual-frequency carrier-phase linear combinations and the precise-positioning
prep tooling built on them: geometry-free and wide-lane phase, the
narrow-lane code, Melbourne-Wubbena, cycle-slip detection, and Hatch
carrier-smoothed code.
  - [Sidereon.GNSS.Constellation](Sidereon.GNSS.Constellation.md): GNSS constellation identity catalogs and validation helpers.
  - [Sidereon.GNSS.DGNSS](Sidereon.GNSS.DGNSS.md): Code-differential GNSS (DGPS) positioning over single-frequency pseudoranges.
  - [Sidereon.GNSS.Frequencies](Sidereon.GNSS.Frequencies.md): Canonical GNSS carrier-frequency lookups.
  - [Sidereon.GNSS.Geometry](Sidereon.GNSS.Geometry.md): Satellite-geometry and mission-planning layer above the GNSS observables:
from a static receiver position and a precise (SP3) ephemeris, answer the
three planning questions: which satellites are visible, how good is the
geometry (dilution of precision), and when does each satellite rise and set.
  - [Sidereon.GNSS.Ionosphere](Sidereon.GNSS.Ionosphere.md): Single-frequency ionospheric group-delay corrections.
  - [Sidereon.GNSS.IonosphereFree](Sidereon.GNSS.IonosphereFree.md): The dual-frequency ionosphere-free linear combination for code and phase.
  - [Sidereon.GNSS.Navigation.LNAV](Sidereon.GNSS.Navigation.LNAV.md): GPS L1 C/A LNAV navigation message synthesis and decoding (subframes 1-3).
  - [Sidereon.GNSS.Navigation.LNAV.Ephemeris](Sidereon.GNSS.Navigation.LNAV.Ephemeris.md): GPS LNAV clock and ephemeris parameters in engineering units.
  - [Sidereon.GNSS.Observables](Sidereon.GNSS.Observables.md): Predict the GNSS observables a receiver at a known ECEF position would see for
a satellite, from a precise (SP3) or broadcast ephemeris source.
  - [Sidereon.GNSS.Positioning](Sidereon.GNSS.Positioning.md): GNSS single-point positioning (SPP): recover a receiver position, clock bias,
and geometry diagnostics from one epoch of pseudorange observations against a
precise SP3 ephemeris or a broadcast navigation product.
  - [Sidereon.GNSS.PrecisePositioning](Sidereon.GNSS.PrecisePositioning.md): Carrier-phase precise-positioning primitives.
  - [Sidereon.GNSS.QC](Sidereon.GNSS.QC.md): Measurement-quality control for single-point positioning.
  - [Sidereon.GNSS.RINEX.Observations](Sidereon.GNSS.RINEX.Observations.md): RINEX 3 observation products: parse a station's observation file, expose its
header (including the surveyed `APPROX POSITION XYZ`, optional antenna
`DELTA H/E/N` offset, and carrier phase-shift records), and extract the
single-frequency pseudoranges that `Sidereon.GNSS.Positioning.solve/4` consumes.
  - [Sidereon.GNSS.RTK](Sidereon.GNSS.RTK.md): RTK-facing carrier/code double-difference primitives.
  - [Sidereon.GNSS.ReducedOrbit](Sidereon.GNSS.ReducedOrbit.md): A compact, fitted mean-element approximation of a satellite's orbit.
  - [Sidereon.GNSS.ReducedOrbit.Piecewise](Sidereon.GNSS.ReducedOrbit.Piecewise.md): A long position track approximated by a sequence of contiguous, independently
fitted `Sidereon.GNSS.ReducedOrbit` segments.
  - [Sidereon.GNSS.SP3](Sidereon.GNSS.SP3.md): SP3-c / SP3-d precise-ephemeris products (IGS precise orbits + clocks).
  - [Sidereon.GNSS.Signal.CA](Sidereon.GNSS.Signal.CA.md): GPS L1 coarse/acquisition (C/A) code generation and correlation.
  - [Sidereon.GNSS.Signal.Correlator](Sidereon.GNSS.Signal.Correlator.md): Baseband simulation, correlation, and acquisition for the GPS L1 C/A signal.
  - [Sidereon.GNSS.SolutionReport](Sidereon.GNSS.SolutionReport.md): A consolidated, read-only diagnostic for a single-point-positioning result.
  - [Sidereon.GNSS.Time](Sidereon.GNSS.Time.md): Epoch conversions shared by the GNSS correction wrappers.
  - [Sidereon.GNSS.Troposphere](Sidereon.GNSS.Troposphere.md): Neutral-atmosphere (tropospheric) signal-delay corrections.
  - [Sidereon.GNSS.Velocity](Sidereon.GNSS.Velocity.md): Recover receiver velocity and clock drift from one epoch of range-rate or
Doppler observations against a precise SP3 or broadcast ephemeris source.

- Data Sources
  - [Sidereon.CelesTrak](Sidereon.CelesTrak.md): Fetch TLEs and orbital data from CelesTrak.
  - [Sidereon.Constellation](Sidereon.Constellation.md): Manage and propagate satellite constellations.
  - [Sidereon.GNSS.Data](Sidereon.GNSS.Data.md): Optional fetch-and-cache layer for GNSS products (SP3, RINEX clock, broadcast
navigation, IONEX).
  - [Sidereon.GNSS.Data.Cache](Sidereon.GNSS.Data.Cache.md): Local, on-disk cache for decompressed GNSS products, with atomic writes,
SHA-256 integrity, gzip decompression (with a bomb guard), and a JSON
provenance sidecar.
  - [Sidereon.GNSS.Data.Catalog](Sidereon.GNSS.Data.Catalog.md): Static, pure catalog of GNSS analysis centers and the rules that turn a
product specification into a canonical filename and a full archive URL.
  - [Sidereon.GNSS.Data.Product](Sidereon.GNSS.Data.Product.md): A GNSS product specification: the analysis center, content type, calendar
date, temporal sampling, and optional issue time that together identify one
archived file.

- Batch Analysis
  - [Sidereon.Nx](Sidereon.Nx.md): Batch/tensor analysis helpers for Sidereon.
  - [Sidereon.Nx.Coverage](Sidereon.Nx.Coverage.md): Higher-level batched access and coverage metrics.

  - [Sidereon.Nx.Geometry](Sidereon.Nx.Geometry.md): Tensorized geometry helpers.
  - [Sidereon.Nx.RF](Sidereon.Nx.RF.md): Tensorized RF helpers for large access and coverage studies.

  - [Sidereon.Nx.Visibility](Sidereon.Nx.Visibility.md): Tensorized visibility products built on top of `Sidereon.Nx.Geometry`.

- Format
  - [Sidereon.Format.OMM](Sidereon.Format.OMM.md): Parse and encode CCSDS Orbit Mean-Elements Messages (OMM).
  - [Sidereon.Format.TLE](Sidereon.Format.TLE.md): Parse and encode Two-Line Element sets.

## Mix Tasks

- [mix gnss.broadcast_diff](Mix.Tasks.Gnss.BroadcastDiff.md): Report broadcast-ephemeris accuracy: the orbit and clock differences between a
RINEX broadcast navigation product and a precise SP3 product, per satellite and
overall (3D plus radial / along-track / cross-track RMS and max). This is the
command-line front end for `Sidereon.GNSS.BroadcastComparison`.

