BepiColombo is a European-Japanese mission that has been planned to Mercury and is set to launch in 2018.
In order to create a three-dimensional map of the Milky Way, BepiColombo and another mission called Gaia, were approved in 2000. ESA then in 2004 issued a request for proposal for the BepiColombo MPO payload. The payload is the part of the spacecraft that including scientific investigations performs the main functions of the mission. The payload instruments were selected later that year. ESA's science program committee in November 2009 gave the final approval for BepiColombo's redesigned mission.
The launch date of the mission had been pushed back several times. After Astrium looked at the development of several components of the spacecraft, the target of July 2014 got delayed to August 2015 and then they determined that they couldn't make the earlier deadline. Subsequent delays in different parts of the mission development pushed the launch date back to 2016, 2017 and then finally to 2018. In June 2013 the total estimated cost of the mission was calculated to be 650 million Euros.
Again, continuing its history, after a major electrical problem was found during a test of MTM BepiColombo's launch date in April 2018 was then further delayed six months to October 2018.
When the announcement was made in late 2016, ESA said it forecasted no impact to the science return of the mission.
The spacecraft making the use of several gravity assists from other planets along the way will take about seven years to get to Mercury. It will fly by Earth and Venus in 2020, Venus in 2021 and Mercury itself between 2021 and 2025. By the December of 2025, in order to be captured by Mercury's gravity, these flybys will slow down the spacecraft enough.
The BepiColombo spacecraft consists of:
Mercury Planetary Orbiter (MPO): The main spacecraft is ESA’s Mercury Planetary Orbiter (MPO). It will map the planet and study the surface and internal composition of Planet Mercury.
Mercury Magnetospheric Orbiter (MMO): It will observe the magnetic field and the magnetosphere. Japan’s JAXA is responsible for the Mercury Magnetospheric Orbiter (MMO).
Mercury Transfer Module(MTM): It contains four T6 ion thrusters which are located at the bottom of the spacecraft. The module will carry both orbiters.
Japan's MMO with occasional startups to make sure that the spacecraft is operating properly will be dormant during the interplanetary cruise. Europe's MPO will communicate with Earth and also command the Japanese spacecraft and the MTM until the three components get separated.
Just before Mercury orbit is achieved, the MTM will separate from the orbiters. Then, in order to perform scientific investigations of Mercury, the two spacecraft will each be put in separate orbits. While Japan's MMO will have an orbit of 9.3 hours, Europe's MPO will have an orbit of about 2.3 hours. The mission is expected to last for one Earth year, which is the equivalent of four Mercury years. Also if funding allows and the two spacecraft remain in good health, it may be extended for an additional Earth year.
ESA noted that going to Mercury would help scientists not only understand how the planet had formed, but also give more information generally about the solar system's formation.
The aim of the BepiColombo mission is:
To investigate Planet Mercury’s magnetic field, magnetosphere and both its surface and interior.
To make a complete map of Mercury at different wavelengths. This will allow to map the planet’s mineralogy and elemental composition and determine whether the interior of the planet is molten or not.
To examine Mercury as a planet: composition, craters, geology and interior structure.
To examine Mercury’s thin atmosphere.
To use the spacecraft’s proximity to the Sun to test the predictions of General Relativity theory with improved accuracy.
To understand the origin and evolution of a planet close to its parent star (our Sun).
This will also be the ESA’s first mission that will be conducted in co-operation with Japan and what is left to see us that what mysteries does it unlock.
BepiColombo - Europe's first mission to Mercury
Video Source: Euronews Knowledge