Cruise phase & flybys

The launch of Bepi Colombo is happily occurred on October 20th 2018 from ESA launch facility in Kourou (French Guyana) by Ariane 5. Both spacecraft (MPO and MMO) now travelling packed in a composite with a propulsion element (Mercury Composite Spacecraft, also called MCS), the Mercury Transfer Module (MTM) and a sunshade cone (MOSIF) to protect the MMO instruments.

The MCS configuration, due to the MOSIF shielding, will allow cruise operations from the MMO only partially for those instruments that will be on the low edge of the shield.

On the contrary, observations by many instruments of the MPO will be allowed, i.e. the instruments pointing out of the +Z direction (that is the nadir direction when orbiting around Mercury). 

The MCS nominal attitude will be defined by the +Y axis pointed to the Sun. This attitude is required to point the radiator (-Y) opposite to the Sun. 

The figure below shows the MCS aspect and axes.






Due to the flight configuration, 8 of 11 instruments onboard MPO will be operative: ISA, MERTIS, MGNS, MORE, PHEBUS, SERENA-MIPA and SERENA-PICAM, SIXS.

Onboard Mio, 4 of 5 will be operative: MPPE (all sensors but HEP-ion), MGF, PWI, MDM.
A table of the 8 MPO instruments that can operate during flybys, together with some details of the scientific goals, operational modes and observing strategy (as at the end of 2018) is available here:

A more updated table will be available by end of July 2020.


During the long cruise to Mercury, and before its arrival on December 5th 2025, BepiColombo will perform 9 flybys:

- 1 at the Earth on April 10th 2020;  (see devoted page here)

- 2 at Venus on October 15th 2020 and August 11th 2021 (see devoted page here);

- 6 flybys at Mercury on: October 2nd 2021, June 23rd 2022, June 20th 2023, September 5th 2024, December 2nd 2024 and January 9, 2025.

The following figure summarizes the many passages and key appointments of BepiColombo cruise on its way to Mercury:





Though originally not planned, as the mission development went on, a whole plan for cruise scientific operations was built.

In these pages, as the many appointments approach, we will put all the information we can to report and support the science activities.