The final stages of Europe’s first mission to the planet Mercury are underway as the European Space Agency (ESA) prepares to launch satellite BepiColombo from its launch site in Kourou French Guiana.
Once the 6.4 meter stacked satellite assembly is on an Earth escape trajectory, it will take seven years to reach Mercury after traveling over nine billion kilometres.
The BepiColombo mission contains two orbiters, the Mercury Planetary Orbiter designed by Europe and the Mercury Magnetospheric Orbiter developed by the Japanese.
David Rothery, Professor of Planetary Geosciences at the Open University commented in a statement released Thursday: “We really need to understand Mercury better.”
“So much about it seems wrong for a planet that close to the Sun, so maybe it originated further out. A collision with the proto-Earth or proto-Venus could be what robbed it of so much of its original rock.”
“As a volcanologist though, one aspect that really impresses me about Mercury is all the volcanic explosion vents. They are spectacular evidence of violent eruptions, powered by escaping gas that recurred for much of the past four billion years.”
Mercury Planetary Orbiter
A major scientific component on the Mercury Planetary Orbiter was developed by the UK Space Agency and the University of Leicester. The Mercury Imaging X-ray Spectrometer (MIXS) will use X-ray optics to analyse small-scale features on the surface of the planet to determine their composition.
Emma Bunce Professor of Planetary Plasma Physics at the University of Leicester said in a statement: “The MIXS is designed to measure fluorescent X-ray photons from the surface of Mercury which will give us details of the elemental composition, and hence provide insight on the formation and evolution of the planet.”
“MIXS will also explore how the charged particle environment interacts with the surface. The dual system of MIXS will allow a good global coverage of the planet using the efficient collimator (MIXS-C) design and will provide unprecedented detail of local-scale features using the first true imaging telescope (MIXS-T) for a planetary mission.”
Farnborough-based defence technology developer QinetiQ supplied the electric propulsion system that will be used by the satellites.
The QinetiQ T6 ion thrusters have an advantage over traditional chemical propulsion systems. Chemical thrusters have a limit on performance controlled by the amount of energy in a chemical reaction. With ion thrusters the propellant is ionised first and then accelerated by electrical energy gathered by the crafts solar panels.
Peter Randall, Electric Propulsion Systems Engineer, QinetiQ, said: “The new T6 ion thrusters have been designed to work for long periods in extremely hostile environments and, powered by solar energy, will enable the spacecraft to reach maximum speed with minimal fuel consumption.”
Mercury Magnetosphere Orbiter
The Japanese Mercury Magnetosphere Orbiter is tasked with exploring Mercury’s magnetosphere, which was first discovered to exist by the Mariner 10 probe in 1973, which was also the last mission to mercury.
The satellite will also analyses the solar winds as they flow through Mercury’s magnetosphere.
A key concern when the satellites were in the development stage was the extreme temperature conditions they would have to operate under.
Most of the sensitive scientific instruments work at room temperature, but Mercury’s surface temperature is 450 degrees Celsius, with the shaded side of the planet experience low temperatures of -180 C.
To counteract these conditions and protect the scientific equipment the craft is covered with multi-layered insulation. The material is constructed using 49 layers of ceramics and aluminium.
Dr Graham Turnock Chief Executive of the UK Space Agency commented in released statement that: “UK scientists, engineers and technicians have played a vital role in developing BepiColombo and the incredibly sophisticated set of scientific instruments on board. The international collaboration involved in this mission shows how our leading role in the European Space Agency is ensuring the UK thrives in the new space age, bringing real benefits to UK companies and scientists.”