| Description: The orbit_number attribute identifies the number of the orbital revolution of a spacecraft around a target body. For MESSENGER, the orbit number was incremented at apoapsis. For observations made before the spacecraft was in orbit, orbit_number has no value, and its nilReason attribute is "inapplicable". |
| Namespace Id: mess | Steward: ppi | Class Name: MESSENGER | Type: ASCII_NonNegative_Integer |
| Minimum Value: 0 | Maximum Value: 18446744073709551615 | Minimum Characters: None | Maximum Characters: None |
| Unit of Measure Type: None | Default Unit Id: None | Attribute Concept: None | Conceptual Domain: INTEGER |
| Status: Active | Nillable: true | Pattern: [0-9]+ |
| Permissible Value(s) | No Values | |