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Space Science
ESA is also building the Mercury Transfer Module
(MTM), which will carry the two orbiters from Earth
to Mercury. Upon arrival, the transfer module will
be jettisoned and the two orbiters will separate.
The European orbiter, called MPO (Mercury
Planetary Orbiter), carries 11 scientific payloads
that will investigate Mercury’s gravitational field in
detail, test Einstein’s theory of general relativity to a
greater precision than ever before, and measure the
topography and surface morphology of Mercury.
Instruments include the Mercury Gamma-ray
and Neutron Spectrometer (MGNS), the Mercury
Imaging X-ray Spectrometer (MIXS) and the
Search for Exosphere Refilling and Emitted Neutral
Abundances (neutral and ionised particle analyser),
or SERENA for short.
ESA is also building the MMO Sunshield and
Interface Structure (MOSIF), which provides
thermal protection, and the mechanical
and electrical interfaces for the Mercury
Magnetospheric Orbiter (MMO), a spinning
spacecraft provided by JAXA.
It will carry a payload of five advanced scientific
experiments, including an ion spectrometer,
electron energy analyser, magnetometer, cold and
energetic plasma detectors, plasma wave analyser,
and imager. These will help to study the structure
and dynamics of Mercury’s magnetic field and
observe the dust which makes up the planet’s
atmosphere, in order to try and understand how
exactly it is released.
The spacecraft will be powered by a single-sided,
three-panelled solar array that uses Optical Solar
Reflectors (OSRs) for temperature control and can
provide up to 1000 W of electrical power during full
science operation phases.
BepiColombo has been designed to complement
the findings of MESSENGER, though the MPO
will have a much less elliptical orbit that will allow
the spacecraft to study the southern hemisphere
of Mercury almost as accurately as the northern
hemisphere. Having a dual spacecraft such as MPO
and MMO, has the advantage of being able to study
two regions of the planet at the same time.
BepiColombo will provide global spectral
mapping of the surface of Mercury with a better
resolution than MESSENGER and in a different
wavelength range. Finally, BepiColombo will look
for the crater left by MESSENGER on the surface of
Mercury in 2015 and study it to understand the rate
of space weathering.
Trials and tribulations
The mission will be completed by a consortium of
industries, and is led by Airbus Deutschland, with
acquired over 250,000 images and extensive data
sets and making many important discoveries.
But perhaps to be expected, many questions still
remain unanswered.
How ‘Bepi’ got its name
It is in honour of Giuseppe Colombo that the
European Space Agency (ESA) decided to name
its first mission to Mercury ‘BepiColombo’ (in
northern Italy Bepi is short for Giuseppe). The
mission has been developed in collaboration with
the Japanese Space Agency (JAXA) and consists
of two separate spacecraft, one provided by JAXA
and one provided by ESA with both having their
own mission agendas.
Unpacking the MMO at
ESTEC in The
Netherlands.
ESA
