1991-050A
The European Space Agency's ERS-1 Earth Resources Satellite was launched on 1991 Jul 17 into a sun-synchronous orbit. Built by Dornier but based on Matra's SPOT Mk 1 bus, ERS 1 carried a 10-m x 1m SAR antenna used by the 5.3GHz Active Microwave Instrument, as well as altimeters and laser reflectors.
The orbit adjust engine restores the orbit when it drifts by 1 km, in a two-burn maneuver half an orbit apart. The burns are needed every 2 weeks at solar maximum, once a month otherwise, with inclination maneuvers every 9 to 10 months.
| ERS 1 | |||
| Date | Time | Event | Orbit |
|---|---|---|---|
| 1991 Jul 17 | 0146:31 | Launch by Ariane | |
| T+2:37 St 1 sep | |||
| T+2:40 St 2 MES | |||
| T+3:20 Fairing 02 sep | |||
| T+4:46 St 2 sep | |||
| T+4:51 St 3 MES | |||
| 0203:16 | T+16:45 St 3 MECO | ||
| 0204:14 | T+17:43 ERS-1 sep | ||
| 0205:54 | T+19:23 ASAP payloads sep | ||
| 100.44 776 x 782 x 98.52 | |||
| 1991 Jul 20 | TCM | ||
| 1991 Jul 26 | TCM to `Venice orbit' | ||
| 1996 Aug | end of regular ops | ||
| 1997 Jun 22 | 100.54 783 x 785 x 98.5 | ||
| 1997 Jun 25 | TCM COLA 1 m/s to avoid K-614 | 100.58 784 x 788 x 98.6 | |
| 1997 Jun 26 | 100.54 783 x 785 x 98.5 | ||
| 2000 Mar 10 | end of ops | ||
Payload:
- AMI Active Microwave Instrument 5.3 GHz 10mx1m
- SAR imager
- SAR Wave mode
- SAR Wind scatterometer
- RA Radar Altimeter
- ASTR Along Track Scanning Radiometer/Microwave sounder
