A joint European-Japanese mission to the tiniest planet, Mercury, blasted off from French Guiana on its long journey tonight (Oct. 19, Oct. 20 GMT).
That mission, BepiColombo, will spend seven years cruising toward its target, where it will separate into two spacecraft and orbit Mercury for a year — or two, if the mission is extended. The measurements taken there could not only solve lingering mysteries about the innermost planet, but also about the formation of our solar system and neighboring ones. The whole mission cost the European Space Agency (ESA) and Japan Aerospace Exploration Agency (JAXA) almost $2 billion, according to press reports.
https://www.space.com/42195-bepicolombo-mercury-spacecraft-launch-success.html