
The Mars Exploration Joint Initiative (MEJI) is an agreement signed between United States' space agency,
NASA
The National Aeronautics and Space Administration (NASA ) is an independent agencies of the United States government, independent agency of the federal government of the United States, US federal government responsible for the United States ...
, and Europe's space agency,
ESA to join resources and expertise in order to continue the exploration of the planet
Mars
Mars is the fourth planet from the Sun. It is also known as the "Red Planet", because of its orange-red appearance. Mars is a desert-like rocky planet with a tenuous carbon dioxide () atmosphere. At the average surface level the atmosph ...
.
The agreement was signed in
Washington D.C. in October 2009, between NASA administrator Charles Bolden and ESA director-general Jean-Jacques Dordain.
In its hey-day it resulted in a synergy between NASA Mars Science Orbiter and the Aurora ExoMars program, the combination of a flexible collaborative proposal within
NASA
The National Aeronautics and Space Administration (NASA ) is an independent agencies of the United States government, independent agency of the federal government of the United States, US federal government responsible for the United States ...
and
ESA to send a new
orbiter
A spacecraft is a vehicle that is designed to fly and operate in outer space. Spacecraft are used for a variety of purposes, including communications, Earth observation, meteorology, navigation, space colonization, planetary exploration, ...
-carrier to
Mars
Mars is the fourth planet from the Sun. It is also known as the "Red Planet", because of its orange-red appearance. Mars is a desert-like rocky planet with a tenuous carbon dioxide () atmosphere. At the average surface level the atmosph ...
in 2016 as part of the European-led
ExoMars
ExoMars (Exobiology on Mars) is an astrobiology programme of the European Space Agency (ESA).
The goals of ExoMars are to search for signs of past life on Mars, investigate how the Martian water and geochemical environment varies, investigate ...
project.
[MEPAG Report to the Planetary Science Subcommittee]
Author: Jack Mustard, MEPAG Chair. July 9, 2009 (pp. 3) One of the goals was for NASA to provide to Atlas V launches for ExoMars, however in the early 2010s planetary exploration in the USA was not given enough money to fund this plan.
Under the
FY2013 budget President
Barack Obama
Barack Hussein Obama II (born August 4, 1961) is an American politician who was the 44th president of the United States from 2009 to 2017. A member of the Democratic Party, he was the first African American president in American history. O ...
released on 13 February 2012, NASA terminated its participation in ExoMars due to budgetary cuts in order to pay for the cost overruns of the
James Webb Space Telescope
The James Webb Space Telescope (JWST) is a space telescope designed to conduct infrared astronomy. As the largest telescope in space, it is equipped with high-resolution and high-sensitivity instruments, allowing it to view objects too old, Lis ...
. With NASA's funding for this project cancelled, most of ExoMars' plans had to be restructured.
History
Discussions between NASA and ESA began in December 2008, driven by the ESA Ministerial Council's recommendation to seek international cooperation to complete the
ExoMars
ExoMars (Exobiology on Mars) is an astrobiology programme of the European Space Agency (ESA).
The goals of ExoMars are to search for signs of past life on Mars, investigate how the Martian water and geochemical environment varies, investigate ...
mission and to prepare further
Mars robotic exploration missions. At the same time, NASA was reassessing its Mars Exploration Program portfolio after the launch of its
Mars Science Laboratory
Mars Science Laboratory (MSL) is a robotic spacecraft, robotic space probe mission to Mars launched by NASA on November 26, 2011, which successfully landed ''Curiosity (rover), Curiosity'', a Mars rover, in Gale (crater), Gale Crater on Augus ...
was delayed from 2009 to 2011. This provided NASA and ESA with an opportunity to increase cooperation and expand collective capabilities.
The U.S. and Europe have taken the view that they can achieve more together scientifically at Mars if they combine their expertise. And with both parties' current Mars programmes also experiencing financial pressures, the shared approach means the exploration schedule of a mission every two years can be maintained.
The executive board recommended NASA and ESA to establish MEJI, spanning launch opportunities in 2016, 2018 and 2020, with landers and orbiters conducting
astrobiological,
geological
Geology (). is a branch of natural science concerned with the Earth and other astronomical objects, the rocks of which they are composed, and the processes by which they change over time. Modern geology significantly overlaps all other Earth s ...
,
geophysical
Geophysics () is a subject of natural science concerned with the physical processes and properties of Earth and its surrounding space environment, and the use of quantitative methods for their analysis. Geophysicists conduct investigations acros ...
and other high-priority investigations, and leading to the return of soil and rock samples from Mars in the 2020s.

Under the FY2013 Budget President Obama released on February 13, 2012, NASA was forced to pull out of joint Mars missions with Europe due to budgetary cuts,
in order to pay for the cost overruns of the
James Webb Space Telescope
The James Webb Space Telescope (JWST) is a space telescope designed to conduct infrared astronomy. As the largest telescope in space, it is equipped with high-resolution and high-sensitivity instruments, allowing it to view objects too old, Lis ...
.
[ The proposal for the Financial Year 2013 reduced the planetary science budget from $1.5bn to $1.2bn; Although planetary science was a loser in general, Mars exploration was singled out for particular cuts, receiving $360.8m, which amounts to a reduction of almost 40% from the FY2012 estimate.][ The cuts may plunge the field into its biggest crisis since the 1980s and is considered likely to lead to the loss of up to 2,000 high-tech jobs.][
On February 29, 2012, the U.S. House Appropriations subcommittee that oversees NASA funding, rejected the space agency's request to begin shutting down its joint Mars-exploration effort with the European Space Agency, until the issue can be debated thoroughly.] The committee believes that "so radical a change in policy needs and deserves to be fully considered by a process that is more rigorous and more inclusive than the reprogramming notification."
Regardless of the final outcome by the House Appropriations subcommittee, NASA will continue with its own Mars exploration projects: Mars Science Laboratory
Mars Science Laboratory (MSL) is a robotic spacecraft, robotic space probe mission to Mars launched by NASA on November 26, 2011, which successfully landed ''Curiosity (rover), Curiosity'', a Mars rover, in Gale (crater), Gale Crater on Augus ...
, ''MAVEN
MAVEN is a NASA spacecraft orbiting Mars to study the loss of that planet's atmospheric gases to space, providing insight into the history of the planet's climate and water. The name is an acronym for "Mars Atmosphere and Volatile Evolution" w ...
'' orbiter, Mars 2020
Mars 2020 is a NASA mission that includes the rover ''Perseverance (rover), Perseverance'', the now-retired small robotic helicopter ''Ingenuity (helicopter), Ingenuity'', and associated delivery systems, as part of the Mars Exploration Progra ...
rover, and ''InSight
Insight is the understanding of a specific causality, cause and effect within a particular context. The term insight can have several related meanings:
*a piece of information
*the act or result of understanding the inner nature of things or of se ...
'' lander.
Current status
In April 2018, a letter of intent was signed by NASA and ESA that may provide a basis for a Mars sample-return mission. It is unclear if this is a new initiative or a restart of the original Mars Exploration Joint Initiative.
The two agencies would need to draw up the mission architecture, and would be seeking commercial partners to collaborate on any sample-return mission.First Mars round-trip announced in hope for discovery of alien life
Henry Bodkin, ''The Telegraph''. April 2018.
Missions
In its original version, the MEJI vision would have encompassed the following launch opportunities:
*2016: A European-led orbiter
A spacecraft is a vehicle that is designed to fly and operate in outer space. Spacecraft are used for a variety of purposes, including communications, Earth observation, meteorology, navigation, space colonization, planetary exploration, ...
(ExoMars Trace Gas Orbiter
The ExoMars Trace Gas Orbiter (TGO or ExoMars Orbiter) is a collaborative project between the European Space Agency (ESA) and the Russian Roscosmos agency that sent an atmospheric research orbiter and the ''Schiaparelli'' demonstration lande ...
), to study trace gases, including methane in Mars' atmosphere. The mission would also put a static meteorological station on the surface. Europe would handle the entry, descent and landing of this station - a capability it has yet to demonstrate.
*2018: A European rover ( ExoMars rover) would be dispatched to Mars. The U.S. would provide the entry, descent and landing system as being used by the Mars Science Laboratory
Mars Science Laboratory (MSL) is a robotic spacecraft, robotic space probe mission to Mars launched by NASA on November 26, 2011, which successfully landed ''Curiosity (rover), Curiosity'', a Mars rover, in Gale (crater), Gale Crater on Augus ...
.
*2020: Under consideration is a network of very small landers focused on geophysics
Geophysics () is a subject of natural science concerned with the physical processes and Physical property, properties of Earth and its surrounding space environment, and the use of quantitative methods for their analysis. Geophysicists conduct i ...
and the environment.
*NASA would provide Atlas V
Atlas V is an expendable launch system and the fifth major version in the Atlas (rocket family), Atlas launch vehicle family. It was developed by Lockheed Martin and has been operated by United Launch Alliance (ULA) since 2006. Primarily used to ...
launch rockets in 2016 and 2018 ExoMars missions.
*The ultimate aim is a mission to return Mars rock and soils to Earth: the Mars sample return mission, some time in the 2020s.
References
{{Politics of outer space, state=collapsed
Space policy
Exploration of Mars
NASA
European Space Agency