Space Segment Introduction
Overall configuration
Satellite budgets
The major driver for the Polar Platform/Envisat
satellite configuration has been the need to maximise the payload instrument mounting area
and to meet the viewing requirements within the constraints of the Ariane 5 fairing and
interfaces. Additionally, the configuration also has been driven by the reuse of the SPOT
Mk II service module concept and the ERS payload accommodation experience (concept of
instrument electronics in an internal enclosure with externally mounted antennas).

The Envisat satellite in flight
In flight, the major spacecraft longitudinal axis
(the Xs-axis) is normal to the orbit plane, the Ys-axis is closely aligned to the velocity
vector and the Zs-axis is Earth pointing. This configuration concept provides a large,
modular, Earth-facing mounting surface for payload instruments and an anti-sun face for
radiative coolers, free of occultation by satellite subsystem equipment.
For more information on Ariane 5 see: http://www.esa.int/export/esaLA/index.html
For more information on SPOT see: SPOT Mk II Service Module
For more information on ERS see: ERS Heritage

Launch configuration
| |
Dimensions (m) |
Launch
Configuration |
length 10.5 m,
envelope diameter 4.57m |
In-Orbit
configuration |
26m * 10m * 5m |
Dimensions
| |
Mass (kg) |
| Service Module |
2673 |
| Payload Equipment Bay |
1021 |
| Payload Carrier |
2078 |
| Fuel |
319 |
| Payload Instruments |
2118 |
| Total |
8211 |
Mass Budget
| |
Average Power (W) |
| |
Sunlight |
Eclipse |
| Payload |
1841 |
1886 |
| Payload Module |
860 |
527 |
| Service Module |
859 |
684 |
| Total Load |
3560 |
3097 |
| System Capability |
3847 |
3291 |
Power Budget
Keywords: ESA European
Space Agency - Agence spatiale europeenne,
observation de la terre, earth observation,
satellite remote sensing,
teledetection, geophysique, altimetrie, radar,
chimique atmospherique, geophysics, altimetry, radar,
atmospheric chemistry
|