MIO-Mercury Magnetospheric Orbiter’s New Name

JAXA selected MIO as new name for the Mercury Magnetospheric 
Orbiter (MMO) to be launched this Japanese fiscal year. Selection 
process is based on public response to the MMO renaming project 
made during the designated correspondence period, February 20 to 
April 9, 2018. Following are the details:


1 The New Name: MIO

2 Namesake and Background

・The definition of the word mio in the original Japanese is a 
waterway or fairway. It is a fitting name denoting how far the MMO 
mission has come, navigating its course past important research and 
development milestones. It also carries the connotation of wishing 
the spacecraft a safe journey. 
・Historically, markers called mio-tsukushi were posted to guide 
boats sailing at rivers and sea. In traditional Japanese poetry, 
mio-tsukushi interchangeably means working hard without giving up. 
This describes the diligent and tenacious sprit of the MMO project 
team who never ceases to challenge. 
・The spacecraft will travel through the solar wind, a continuous 
stream of plasma that the Sun emits in the Mercury’s magnetosphere. 
The Mercury’s magnetospheric interference constantly affects the 
state of the solar wind in orbit. It conjures up the image of a sea 
vessel underway with its bow heading forward. 
・Mio is easy to say for many, especially those who do not speak 

3 Statistics

Total number of correspondents: 6,494
19 suggested Mio. 3 did Mio-Tsukushi.

4 The Selection Committee Members

Hajime Hayakawa, Project Manager, BepiColombo project team/Professor 
at the Department of Solar System Sciences, the Institute of Space 
and Astronautical Science

Go Murakami, Project Scientist, BepiColombo project team/Assistant 
Professor at the Department of Solar System Sciences, the Institute 
of Space and Astronautical Science

Chisato Ikuta, Director for Education and Public Outreach at the 
Institute of Space and Astronautical Science

Yasunori Matogawa, Emeritus at the Institute of Space and 
Astronautical Science

Naoko Takeuchi, Cartoonist

5 Acknowledgments by Hajime Hayakawa

I thank all who responded for your interest in the MMO. We are at 
the start of the mission with a long way ahead. I hope MIO will 
bring to us a lot of discoveries about the Mercury.

6 Prize

JAXA will send a gift to all who 19 proposers of Mio no sooner than 

Mission Overview: MIO and the International Mercury Exploration 
BepiColombo Mission

BepiColombo, an ESA-JAXA joint mission to explore Mercury, 
comprises of two orbiters - the MPO, Mercury Planetary Orbiter 
and the MIO, Mercury Magnetosphere Orbiter. MPO aims at elucidating
 the surface and internal composition of Mercury. The MIO mission 
is observing the planet's magnetic field and magnetosphere.
JAXA is in charge of the development of the MIO spacecraft and 
controlling its operation at the target orbit, as Japan is adept 
at observations of magnetic field and magnetosphere. ESA controls 
BepiColombo launch and flight to Mercury and orbital insertions. 
The development and operation of the MPO is also part of the 
mission performed by ESA. Ariane 5 will launch the tandem 
satellites. After entering the planet's orbit, detached orbiters 
are scheduled for approximately year-long observation mission, 
which both agencies will cooperatively engage in.

[Reference] Related Links:

Mercury Exploration Mission "BepiColombo"

Mercury Magnetosphere Orbiter (MMO) /BepiColombo (ISAS)

BepiColombo Mercury Exploration


National Research and Development Agency Japan Aerospace Exploration 
Agency (JAXA)