Smaller, faster, cheaper – ESP-MACCS chosen as ESA’s first Earth observation Scout mission
03 Dec 2020



A new mission to study how climate change affects the processes in the Earth’s atmosphere has been selected by the European Space Agency (ESA).


​​​Artist impression of the ESP-MACCS constellation in orbit.

Credit: GomSpace​

This UK-Danish led mission will be smaller and cheaper than the traditional ESA Earth observation satellites and will be ready for launch in just 4 years. It has been selected as part of a new programme to develop small, agile spacecraft to complement the existing fleet while proving new techniques in Earth observations which could be scaled up for future missions.

ESP-MACCS (Earth System Processes Monitored in the Atmosphere by a Constellation of CubeSats), is the first of these missions to be chosen and is being led by GomSpace in Denmark with science instruments provided by the Science and Technology Facilities Council's RAL Space.

ESA's Director of Earth Observation Programmes, Josef Aschbacher, announced the decision to move forward with EPS-MACCS today​ at the 16th Appleton Space Conference. RAL Space will be responsible for the mission's thermal infrared spectrometer.

Dr Aschbacher said: “The selection of this first Scout mission is a key programmatic milestone for Earth Observation and a significant step forward in our efforts to embrace the age of New Space.

“With EPS-MACCS now heading into negotiations, the plan is now also to further assess the feasibility of implementing additional Scout mission proposals that we received."

A constellation of three satellites will focus on the tropics and subtropics. Rapidly growing mega-cities and increased occurrence of wildfires in these geographical areas generates greenhouse and polluting gasses which are quickly transported high into the atmosphere. This affects processes taking place in this sensitive region which in turn, impacts the climate at the surface.

ESP-MACCS will monitor the vital ozone layer which protects the Earth from harmful ultra violet rays from the Sun. It will also make highly accurate measurements of greenhouse gases, including water vapour, covering the whole of the tropics within a month, allowing scientists to track both spatial and seasonal changes in the state of the high atmosphere.

Dr Damien Weidmann, from RAL Space and lead scientist for ESP-MACCS said: “The mission is packed with innovation, from the way the atmosphere is measured, to the instrumentation used to do the measurements. Exciting scientific insights and knowledge are expected."

The instrumentation for this type of system is usually larger than a washing machine but the team have manage to reduce this to fit within GomSpace's small, toaster-sized cubesat platform with each instrument on board weighing less than 1.3kg.

The mission is able to meet ESA's stringent requirements for a small, light spacecraft with a rapid turnaround to launch because the instruments on board build on more than 10 years of research and development by scientists at RAL Space, the UK's national space laboratory.

While this will be the first technology of this kind and size to fly on board a spacecraft the technology developed has already been used for a number of applications here on the ground. Some aspects of the technology underpinning ESP-MACCS have been exploited for the development of non-invasive breath analysis for early medical diagnosis and environmental monitoring.

Dr Graham Turnock, Chief Executive of the UK Space Agency, said: “The UK is leading the way in using space to take the fight to climate change and is making Earth observation satellites one of the most important weapons in our arsenal.

“This new mission builds on these strengths in an exciting and innovative way, using satellites the size of a toaster to demonstrate techniques much faster and cheaper than traditional missions."