Non-gravitational and aerodynamic accelerations
Thematic areas: Thermosphere, Acceleration measurements
Applicable missions: Swarm
Applicable spacecraft: Swarm-A, Swarm-B, Swarm-C
Time series of non-gravitational and aerodynamic accelerations obtained by Precise Orbit Determination (POD).
N/A
(delivered separately)
| Variable | Units | Description | Dim | Type |
|---|---|---|---|---|
| time | - | Time of observation | 1 | CDF_EPOCH |
| acc_pod | m/s/s | Total non-gravitational acceleration in satellite reference frame (X, Y, Z) | 3 | CDF_DOUBLE |
| acc_pod_aero | m/s/s | Aerodynamic acceleration in satellite reference frame (X, Y, Z) | 3 | CDF_DOUBLE |
| validity_flag_tot | - | Flag: 0 = nominal data, 1 = anomalous data | 1 | CDF_INT1 |
| validity_flag | - | Flag: 0 = nominal data, 1 = anomalous data | 1 | CDF_INT1 |
| Product identifier | ACCxPOD_2_ |
| Definition | Time series of non-gravitational and aerodynamic accelerations obtained by POD |
| Input data | GPSx_RO_1B, STRxATT_1B, SC_xDYN_1B, External data from CODE |
| Input time span | 30 hr (daily batches with overlap) |
| Spatial representation | N/A |
| Time representation | UTC (seconds – s), time step = 30 sec |
| Units | m/s2 |
| Resolution | 64 bit double precision floating point number format |
| Uncertainty | 10-7 m/s2 variance for along-track and cross-track directions |
| Quality indicator | Validation report DNSxVAL_2_ |
| Data volume | < 10 Kb per satellite per day |
| Output data | CDF file with time series of accelerations |
| Output time span | 24 hr |
| Update rate | 1 month |
| Latency | 21 days |
| Notes | The total non-gravitational acceleration (variable "acc_pod") is used for calibrating the accelerometer data (in product "ACCxCAL_2"), whereas the aerodynamic acceleration (variable "acc_pod_aero") is used for the calculation of thermosphere density (in product "DNSxPOD_2"). |
Level 2 Product Description:
N/A