Astrophyzix™ Digital Observatory
Orbit Determination Engine
IOD + Differential Correction | JPL CAD Live Data | Manual MPC Astrometry
Live API
JPL GM DE440
RKF45 / Dormand-Prince
N-Body
BCRS/TDB
State:
IDLE
--:--:-- UTC
1. Data Sourcev
JPL CAD
NEOCP Scout
Manual MPC
Live close-approach data from NASA JPL SBDB. Fetches all objects within the selected date window and distance. Results are informational -- to run Orbit Determination paste MPC observations in the Manual MPC tab.
Distance MaxLunar Distances
Max LD Date Min Date Max
Live unconfirmed objects from NASA CNEOS Scout (NEOCP). This shows summary data only. To run OD on any of these objects, obtain their MPC astrometry from the Minor Planet Center and paste it in the Manual MPC tab.
Paste MPC 80-column astrometric observations below. Minimum 3 observations required. Get observations from the Minor Planet Center or press Load Sample to test the pipeline.
MPC 80-Column Observations
Observations loaded. Press Run Orbit Determination.
2. OD Parametersv
Integrator
Perturbers
Max DC Iterations
Convergence Tol
All computations in BCRS J2000.0. TDB timescale. JPL GM DE440. Float64Array state vectors.
3. Computation Logv
DC Progress--
RMS Residual-- arcsec
4. Orbital Elementsv
Run OD to compute orbital elements.
5. Orbit Visualizerv
Ecliptic projection | Sun at focus | Cyan = computed orbit | Orange dot = perihelion
6. Observation Residualsv
7. Uncertainty Estimatesv
Computed after OD converges.
8. Scientific Methodologyv
Gauss IOD.
Three observations (first, middle, last) selected from the arc. Direction unit vectors from RA/Dec. Gauss scalars from timing ratios. Heliocentric distance r2 at obs 2 solved by Newton-Raphson on the two-body energy equation. F-G Lagrange coefficients yield velocity at epoch 2. State propagated to mid-arc epoch via RKF45.
RKF45 / Dormand-Prince. Embedded 4th/5th order pair (DOPRI5). Adaptive step: accepted when error norm less than 1; step factor = 0.9 * err^-0.2 clamped [0.1, 5]. atol=1e-12 AU, rtol=1e-11. Float64Array[6] state vectors [x,y,z,vx,vy,vz] in AU and AU/day.
N-Body Perturbations. Sun + 8 planets. JPL GM constants DE440. Planet positions from Keplerian elements with secular rates (Meeus Table 31.a). Indirect barycentric terms included.
Differential Correction. Batch WLS on 6-element Cartesian state. Partials by central finite difference. Normal equations solved by Cholesky decomposition. Line search prevents divergence.
Reference Frame. BCRS J2000.0 equatorial. TDB via Fairhead-Bretagnon: TDB = TT + 0.001658 sin(Msun + 0.01671 sin(Msun)) seconds. UTC + 37s + 32.184s = TT.
Data Sources. CAD: ssd-api.jpl.nasa.gov/cad.api (confirmed JPL close approaches). NEOCP: ssd-api.jpl.nasa.gov/scout.api (unconfirmed, summary only). MPC astrometry: minorplanetcenter.net. CORS relay: allorigins-get then corsproxy.io then allorigins-raw.
RKF45 / Dormand-Prince. Embedded 4th/5th order pair (DOPRI5). Adaptive step: accepted when error norm less than 1; step factor = 0.9 * err^-0.2 clamped [0.1, 5]. atol=1e-12 AU, rtol=1e-11. Float64Array[6] state vectors [x,y,z,vx,vy,vz] in AU and AU/day.
N-Body Perturbations. Sun + 8 planets. JPL GM constants DE440. Planet positions from Keplerian elements with secular rates (Meeus Table 31.a). Indirect barycentric terms included.
Differential Correction. Batch WLS on 6-element Cartesian state. Partials by central finite difference. Normal equations solved by Cholesky decomposition. Line search prevents divergence.
Reference Frame. BCRS J2000.0 equatorial. TDB via Fairhead-Bretagnon: TDB = TT + 0.001658 sin(Msun + 0.01671 sin(Msun)) seconds. UTC + 37s + 32.184s = TT.
Data Sources. CAD: ssd-api.jpl.nasa.gov/cad.api (confirmed JPL close approaches). NEOCP: ssd-api.jpl.nasa.gov/scout.api (unconfirmed, summary only). MPC astrometry: minorplanetcenter.net. CORS relay: allorigins-get then corsproxy.io then allorigins-raw.
9. Parameter Provenancev
Status: Awaiting first OD run.
Engine: Astrophyzix ODE V2.0 | IOD: Gauss | Integrator: RKF45/DOPRI5
GM Source: JPL DE440 embedded | Frame: BCRS J2000.0 | TDB timescale
Float64 state vectors: yes | IndexedDB cache: active
Engine: Astrophyzix ODE V2.0 | IOD: Gauss | Integrator: RKF45/DOPRI5
GM Source: JPL DE440 embedded | Frame: BCRS J2000.0 | TDB timescale
Float64 state vectors: yes | IndexedDB cache: active