Joint Europa Mission (JEM) a multi-scale study of Europa to characterize its habitability and search for extant life
Author(s)
Type
Journal Article
Abstract
Europa is the closest and probably the most promising target to search for extant life in the Solar System, based on
complementary evidence that it may fulfil the key criteria for habitability: the Galileo discovery of a sub-surface ocean;
the many indications that the ice shell is active and may be partly permeable to transfer of chemical species,
biomolecules and elementary forms of life; the identification of candidate thermal and chemical energy sources
necessary to drive a metabolic activity near the ocean floor. In this article we are proposing that ESA collaborates with
NASA to design and fly jointly an ambitious and exciting planetary mission, which we call the Joint Europa Mission
(JEM), to reach two objectives: perform a full characterization of Europa’s habitability with the capabilities of a Europa
orbiter, and search for bio-signatures in the environment of Europa (surface, subsurface and exosphere) by the
combination of an orbiter and a lander. JEM can build on the advanced understanding of this system which the
missions preceding JEM will provide: Juno, JUICE and Europa Clipper, and on the Europa lander concept currently
designed by NASA (Maize, report to OPAG, 2019). We propose the following overarching goals for our proposed Joint
Europa Mission (JEM): Understand Europa as a complex system responding to Jupiter system forcing, characterise
the habitability of its potential biosphere, and search for life at its surface and in its sub-surface and exosphere. We
address these goals by a combination of five Priority Scientific Objectives, each with focused measurement objectives
providing detailed constraints on the science payloads and on the platforms used by the mission. The JEM observation
strategy will combine three types of scientific measurement sequences: measurements on a high-latitude, low-altitude
Europan orbit; in-situ measurements to be performed at the surface, using a soft lander; and measurements during the
final descent to Europa’s surface. The implementation of these three observation sequences will rest on the
combination of two science platforms: a soft lander to perform all scientific measurements at the surface and subsurface
at a selected landing site, and an orbiter to perform the orbital survey and descent sequences. We describe a
science payload for the lander and orbiter that will meet our science objectives. We propose an innovative distribution
of roles for NASA and ESA; while NASA would provide an SLS launcher, the lander stack and most of the mission
operations, ESA would provide the carrier-orbiter-relay platform and a stand-alone astrobiology module for the
characterization of life at Europa’s surface: the Astrobiology Wet Laboratory (AWL). Following this approach, JEM will
be a major exciting joint venture to the outer Solar System of NASA and ESA, working together toward one of the most
exciting scientific endeavours of the 21st century: to search for life beyond our own planet.
complementary evidence that it may fulfil the key criteria for habitability: the Galileo discovery of a sub-surface ocean;
the many indications that the ice shell is active and may be partly permeable to transfer of chemical species,
biomolecules and elementary forms of life; the identification of candidate thermal and chemical energy sources
necessary to drive a metabolic activity near the ocean floor. In this article we are proposing that ESA collaborates with
NASA to design and fly jointly an ambitious and exciting planetary mission, which we call the Joint Europa Mission
(JEM), to reach two objectives: perform a full characterization of Europa’s habitability with the capabilities of a Europa
orbiter, and search for bio-signatures in the environment of Europa (surface, subsurface and exosphere) by the
combination of an orbiter and a lander. JEM can build on the advanced understanding of this system which the
missions preceding JEM will provide: Juno, JUICE and Europa Clipper, and on the Europa lander concept currently
designed by NASA (Maize, report to OPAG, 2019). We propose the following overarching goals for our proposed Joint
Europa Mission (JEM): Understand Europa as a complex system responding to Jupiter system forcing, characterise
the habitability of its potential biosphere, and search for life at its surface and in its sub-surface and exosphere. We
address these goals by a combination of five Priority Scientific Objectives, each with focused measurement objectives
providing detailed constraints on the science payloads and on the platforms used by the mission. The JEM observation
strategy will combine three types of scientific measurement sequences: measurements on a high-latitude, low-altitude
Europan orbit; in-situ measurements to be performed at the surface, using a soft lander; and measurements during the
final descent to Europa’s surface. The implementation of these three observation sequences will rest on the
combination of two science platforms: a soft lander to perform all scientific measurements at the surface and subsurface
at a selected landing site, and an orbiter to perform the orbital survey and descent sequences. We describe a
science payload for the lander and orbiter that will meet our science objectives. We propose an innovative distribution
of roles for NASA and ESA; while NASA would provide an SLS launcher, the lander stack and most of the mission
operations, ESA would provide the carrier-orbiter-relay platform and a stand-alone astrobiology module for the
characterization of life at Europa’s surface: the Astrobiology Wet Laboratory (AWL). Following this approach, JEM will
be a major exciting joint venture to the outer Solar System of NASA and ESA, working together toward one of the most
exciting scientific endeavours of the 21st century: to search for life beyond our own planet.
Date Issued
2020-11-01
Date Acceptance
2020-04-25
Citation
Planetary and Space Science, 2020, 193
ISSN
0032-0633
Publisher
Elsevier
Journal / Book Title
Planetary and Space Science
Volume
193
Copyright Statement
Crown Copyright © 2020 Published by Elsevier Ltd. All rights reserved. This manuscript is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International Licence http://creativecommons.org/licenses/by-nc-nd/4.0/
Sponsor
The Royal Society
Grant Number
UF150547
Subjects
Science & Technology
Physical Sciences
Astronomy & Astrophysics
Outer planets exploration
Search for life
Jupiter system
Ocean moon
Habitability
HYDRATED SALT MINERALS
HUYGENS PROBE
SULFURIC-ACID
INSTRUMENT
SATELLITES
ATMOSPHERE
SURFACE
EVOLUTION
SECONDARY
PLUME
0201 Astronomical and Space Sciences
Astronomy & Astrophysics
Publication Status
Published
Article Number
ARTN 104960
Date Publish Online
2020-06-27