ele220 Format¶
The ele220 format is an old 220-character string that was created for internal use at the MPC for storing minor planet orbital computation data.
Deprecation Notice
The MPC will deprecate the ele220 format in favor of a new orbit format. This page is provided for reference only.
Limitations:
- Only applies to asteroids; comets and natural satellites are excluded
- Cannot represent parabolic or hyperbolic orbits
- Orbital elements appear twice with differing precision levels
Field Specifications¶
| Character Range | Field Description |
|---|---|
| 0-7 | Packed designation |
| 7-12 | Slope parameter G |
| 12-24 | Packed time of pericenter passage |
| 24-34 | Argument of perihelion, J2000.0 (degrees) |
| 34-44 | Longitude of ascending node, J2000.0 (degrees) |
| 44-54 | Inclination to ecliptic, J2000.0 (degrees) |
| 54-64 | Perihelion distance (AU) |
| 64-74 | Eccentricity |
| 75-80 | Epoch (packed form, TT) |
| 80-90 | Designation (unpacked) |
| 91-96 | Absolute magnitude H |
| 97-102 | Epoch (packed form, TT) |
| 103-108 | Mean anomaly at epoch (degrees) |
| 109-114 | Argument of pericenter, J2000.0 (degrees) |
| 115-120 | Longitude of ascending node, J2000.0 (degrees) |
| 121-126 | Inclination to ecliptic, J2000.0 (degrees) |
| 127-132 | Eccentricity |
| 133-140 | Semi-major axis (AU) |
| 141-144 | Number of oppositions |
| 144-150 | Arc length or observation year range |
| 150-156 | Number of observations |
| 157 | MPC U parameter |
| 159-168 | Computer name |
| 169-178 | Publication reference |
| 179-184 | Time of first observation (packed form) |
| 185-190 | Time of last observation (packed form) |
| 190-196 | Post-fit RMS |
| 197 | Perturber scheme |
| 199-202 | Coarse perturber indicator |
| 203-207 | Precise perturber indicator |
| 208-210 | Propagator step-size (internal use only) |
| 212-214 | Packed 'numberability' score |
| 214 | Current opposition score |
| 215-222 | RUNOFF score |