First Earth Explorer Core Mission

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Earth Observation Programmes Directorate
Gravity Field and Steady-State Ocean Circulation
Explorer GOCE

• First Earth Explorer Core Mission
• First ESA Mission dedicated to the exploration of
  the Earth Gravity Field

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Earth Observation Programmes Directorate
GOCE

• Mission Objectives
• Determine the Earths Gravity field with an
  accuracy of 1 mgal(i.e. 1 millionth of Earth
  Gravity).
• Determine the geoid ( equipotential surface of a
  hypothetical ocean at rest) with an accuracy of 1
  cm.
• Achieve this at length scales down to L 100 Km.

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Earth Observation Programmes Directorate
GOCE

• System / Configuration
• Aerodynamic shape with low drag profile along
  flight direction.
• Electrostatic Gravity Gradiometer to measure
  gravity gradient tensor.
• GPS Receiver to recover low frequency gravity
  components.
• Orbit maintenance and in-track drag compensation
  by Ion thruster.
• Cross-track/radial drag compensation by field
  emission electric thrusters.
• Solar generator distributed over two fixed wings
  and half of satellite body.
• Dimensions 5m long, 1m f
• Mass at launch 1.2 tons.

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Earth Observation Programmes Directorate
GOCE

• Present Status
• Space Segment is at the beginning of Phase
  C/D(i.e. development / production phase).
• Industrial consortium has been established via
  open competitions.
• Future Planning
• Ground Segment procurement activities will start
  before end 2002 with the release of the
  Invitation to Tender for the Payload Data Segment
  development.
• Predicted launch date is mid February 2006.

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Earth Observation Programmes Directorate
GOCE
Industrial core team