Bepi Colombo will provide the best understanding of Mercury to date. It consists of two individuals orbiters, the Mercury Planetary Orbiter (MPO), that will map the planet, and the Mercury Magnetospheric Orbiter (MMO), that will investigate its magnetosphere.

The first spacecraft that got close to Mercury with 3 flybys is Mariner 10.

The trajectory of these flybys was proposed by the Italian scientist Giuseppe(Bepi) Colombo (1920-1984). He is also known by the study of the mystery that the rotation period (58 days) and the revolution period around the sun (88 days) of Mercury is in the 2:3 resonance.





MMO and MPO will be combined with Solar Electric Propulsion Module (SEPM) and Chemical Propulsion Module (CPM), both provided by ESA. The unified module will be launched with Ariane 5 rocket and travel to Mercury. The launch date, according to the plan of October 2012, is scheduled for August 2015.

In the interplanetary space, the unified module will be propelled by the SEPM which makes “small but steady/continuous” propulsion, associated with swing-bys with the Moon, Venus, and Mercury. Just before the insertion into the orbit around Mercury, SEPM will be separated. After the separation of SEPM, the unified module will make a rapid slow-down by the CPM to come into the planned MMO orbit around Mercury. MMO will be separated at this stage to begin independent operations, and the CPM will make the second propulsion for lowering the orbit of MPO. Finally, MPO will be separated from the CPM.

Both spacecrafts will make scientific observations for more than 1 earth year (4 Mercury years).


BepiColombo is a joint mission between ESA and the Japanese Aerospace Exploration Agency (JAXA), executed under ESA leadership, being the first large-sized Europe-Japan joint mission.

ISAS/JAXA is responsible for the MMO while ESA is responsible for the MPO.


BELA – BepiColombo Laser Altimeter
Co-Principal Investigator Co-Principal Investigator
Nicolas Thomas
University of Bern, Department of Space Research
Tilman Spohn
DLR Institut für Planetenforschung, Berlin
ISA – Italian Spring Accelerometer
Principal Investigator
Valerio Iafolla
INAF-IAPS Istituto di Astrofisica e Planetologia Spaziali, Rome
MERMAG – Magnetic Field Investigation
Principal Investigator Co-Principal Investigator
Karl-Heinz Glassmeier
Technische Universität Braunschweig
C.M. Carr
The Blackett Laboratory, Imperial College London
United Kingdom
MERTIS – Mercury Radiometer and Thermal Imaging Spectrometer
Principal Investigator Co-Principal Investigator
Harald Hiesinger
University of Münster
Jörn Helbert
DLR Institut für Planetenforschung, Berlin
MGNS – Mercury Gamma-Ray and Neutron Spectrometer
Principal Investigator Co-Principal Investigator
Igor Mitrofanov
Russian Academy of Sciences, Space Research Institute – IKI
Russian Federation
Leonid Gurtvits
Joint Institute for VLBI in Europe – JIVE
The Netherlands
MIXS – Mercury Imaging X-ray Spectrometer
Principal Investigator Co-Principal Investigator
Emma Bunce
Space Research Centre
University of Leicester
United Kingdom
K. Muinonen
University of Helsinki, Department of Physics
MORE – Mercury Orbiter Radio science Experiment
Principal Investigator Co-Principal Investigator
Luciano Iess
University of Rome “La Sapienza”
Sami Asmar
Jet Propulsion Laboratory/NASA, Pasadena
PHEBUS – Probing of Hermean Exosphere by Ultraviolet Spectroscopy
Principal Investigator Co-Principal Investigator Co-Principal Investigator
Eric Quemerais
LATMOS-IPSL, Guyancourt
S. Okano
Planetary Plasma & Atmospheric Research Center, Tohoku University, Sendai
O. Korablev
Space Research Institute-IKI, Moscow
Russian Federation
SERENA – Search for Exosphere Refilling and Emitted Neutral Abundances (neutral and ionised particle analyser)
Principal Investigator Co-Principal Investigators Co-Principal Investigators
Stefano Orsini
INAF-IAPS Istituto di Astrofisica e Planetologia Spaziali, Rome
S. A. Livi
Southwest Research Institute, San Antonio, Texas
S. Barabash
Swedish Institute of Space Physics (IRF), Kiruna
Herbert Lichtenegger
Space Research Institute, Austrian Academy of Sciences, Graz
SIMBIO-SYS – Spectrometers and Imagers for MPO BepiColombo Integrated Observatory – HRIC, STC, VIHI
Principal Investigator Co-Principal Investigators Co-Principal Investigators
Enrico Flamini
Italian Space Agency – ASI, Rome
F. Capaccioni
INAF-IAPS (Istituto di Astrofisica e Planetologia Spaziali), Rome
P. Palumbo
INAF-Osservatorio Astronomico di Capodimonte, Napoli
G. Cremonese
INAF-Osservatorio Astronomico di Padova
A. Doressoundiram
LESIA-Observatoire de Paris, Meudon
Y. Langevin
Institut d’Astrophysique Spatiale (IAS), Orsay
SIXS – Solar Intensity X-ray and particle Spectrometer
Principal Investigator Co-Principal Investigator
Juhani Huovelin
University of Helsinki, Department of Physics
M. Grande
Institute of Mathematics and Physics, Aberystwyth University
United Kingdom

BepiColombo Instruments


The mission is due for launch in November, 2018 and will reach Mercury in 2024 after a six-year journey towards the inner Solar System, the planned mission lifetime being about one year after the arrival.


The project is named after Professor Giuseppe (Bepi) Colombo (1920-1984) from the University of Padua, Italy, a mathematician and engineer of astonishing imagination. It was he who suggested to NASA how to use a gravity-assist swing-by of Venus to place the Mariner 10 spacecraft in a solar orbit that would allow it to fly by Mercury three times in 1974-5.

This post is also available in: Spanish