History

Introduction
The Polar Platform (PPF)
The mission

Introduction

The PPF and Envisat Programmes have emerged from two basic roots:

• The development of a multimission Polar Platform for future Earth observation missions, initially started as an element of the Columbus Space Station Programme.
• The Polar Orbiting Earth Observation Mission (POEM-1), initially conceived as a combined mission with instruments for scientific application, research, and operational meteorology. This mission, to be based on the Polar Platform, was to be the successor of ERS.

The Polar Platform (PPF)

The Polar Platform development activities started in 1990, following the selection of the Polar Platform as a derivative of SPOT-4, by the ESA council. An industrial proposal was submitted and evaluated at the end of 1990 and implemented starting in early 1991. Since then, the following major external programmatic events have taken place:

• deletion of multimission requirements and related activities for cost saving reasons;
• splitting of the first mission POEM-1 into Envisat (the environmental mission) and METOP-1 (the meteorological mission) in mid-1993;
• several iterations on cost savings/descoping actions executed in mid-1993, early 1994, and the end of 1995 to reduce overall programme costs in industry and ESA;

Final negotiations were completed with industry in mid-1995 and the PPF phase C/D contract for the development and integration of the Polar Platform with the Envisat instruments was signed in July 1995.

The mission

The development of the payload instruments for Envisat started after the split of POEM-1 into Envisat and METOP-1 at the Ministerial ESA council meeting in December 1993.

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