Earth Explorers overview
Following the success of the ERS satellites and Envisat, which addressed Earth science issues of a global nature, Earth Explorers are smaller research missions dedicated to specific aspects of our Earth environment whilst demonstrating new technology in space. Earth Explorer missions focus on the atmosphere, biosphere, hydrosphere, cryosphere and the Earth's interior with the overall emphasis on learning more about the interactions between these components and the impact that human activity is having on natural Earth processes.
Designed for research purposes, Earth Explorer missions fall into two categories: 'Core' missions addressing specific areas of great scientific interest, and faster, lower cost 'Opportunity' missions to address areas of immediate environmental concern. Of the six Earth Explorers selected for implementation, three are Core missions and three are Opportunity missions.
GOCE (Gravity Field and Steady-State Ocean Explorer)
Core mission - Launched on 17 March 2009
How does the gravity field affect ocean currents and sea level?
GOCE is dedicated to measuring the Earth's gravity field and modelling the geoid with unprecedented accuracy and spatial resolution to advance our knowledge of ocean circulation, which plays a crucial role in energy exchanges around the globe, sea-level change and Earth interior processes. GOCE will also make significant advances in the field of geodesy and surveying.
SMOS (Soil Moisture and Ocean Salinity)
Opportunity mission - Launched on 2 November 2009
Is climate change accelerating the water cycle?
SMOS is observing soil moisture over the Earth's landmasses and salinity over the oceans. Soil moisture data are urgently required for hydrological studies and data on ocean salinity are vital for improving our understanding of ocean circulation patterns.
Opportunity mission - Launched on 8 April 2010
Are the ice caps shrinking?
CryoSat is acquiring accurate measurements of the thickness of floating sea-ice so that seasonal to inter-annual variations can be detected, and also surveying the surface of continental ice sheets to detect small elevation changes. Data from CryoSat will help determine regional trends in Arctic perennial sea-ice thickness and mass, and determine the contribution that the Antarctic and Greenland ice sheets are making to mean global rise in sea level. This satellite replaces the original CryoSat which was lost owing to a launch failure in 2005.
Opportunity mission - Scheduled for launch in November 2013
How fast is the Earth's magnetic shield weakening against solar radiation?
Swarm is a constellation of three satellites that will provide high-precision and high-resolution measurements of the strength and direction of the Earth's magnetic field. The geomagnetic field models resulting from the Swarm mission will provide new insights into the Earth's interior, further our understanding of atmospheric processes related to climate and weather, and will also have practical applications in many different areas such as space weather and radiation hazards.
ADM-Aeolus (Atmospheric Dynamics Mission)
Core mission - Scheduled for launch in 2015
How does measuring the wind improve weather forecasting?
ADM-Aeolus will be the first space mission to measure wind profiles on a global scale. It will improve the accuracy of numerical weather forecasting and advance our understanding of atmospheric dynamics and processes relevant to climate variability and climate modelling.
EarthCARE (Earth Clouds, Aerosols and Radiation Explorer)
Core mission - Scheduled for launch in 2016
To what extent do clouds and aerosols influence global warming?
EarthCARE is being implemented in cooperation with the Japanese Aerospace Exploration Agency (JAXA), and addresses the need for a better understanding of the interactions between cloud, radiative and aerosol processes that play a role in climate regulation.
Earth Explorer 7: Following ESA's Call for Ideas for the seventh Earth Explorer in 2005 and the subsequent selection in 2009 of three missions – Biomass, CoReH2O and PREMIER – to undergo feasibility study, the Biomass mission was selected in May 2013 to go forward as ESA's seventh Earth Explorer. Biomass aims to provide, for the first time from space, P-band radar measurements that are optimised to determine the amount of biomass and carbon stored in the world’s forests with greater accuracy than ever before.
Earth Explorer 8: As a result of the Call for Proposals for the eighth Earth Explorer released in October 2009, the Florescence Explorer (FLEX) and CarbonSat missions have been approved to move forward to Phase A/B1. Approval was given by ESA's Earth Observation Programme Board on 24 November 2010.
Last update: 31 October 2013