@article{,
    author = {Konstantinidis, Konstantinos; Flores Martinez, Claudio L.; Dachwald, Bernd; Ohndorf, Andreas; Dykta, Paul; Bowitz, Pascal; Rudolph, Martin; Digel, Ilya; Kowalski, Julia; Voigt, Konstantin; Förstner, Roger},
    title = {A lander mission to probe subglacial water on Saturn's moon Enceladus for life},
    editor = {},
    booktitle = {},
    series = {},
    journal = {Acta Astronautica},
    address = {},
    publisher = {},
    edition = {},
    year = {2015},
    isbn = {},
    volume = {73},
    number =  {106},
    pages = {63-89},
    url = {http://www.sciencedirect.com/science/journal/00945765/106},
    doi = {},
    keywords = {},
    abstract = {The plumes discovered by the Cassini mission emanating from the south pole of Saturn's
moon Enceladus and the unique chemistry found in them have fueled speculations that
Enceladus may harbor life. The presumed aquiferous fractures from which the plumes
emanate would make a prime target in the search for extraterrestrial life and would be
more easily accessible than the moon's subglacial ocean.
A lander mission that is equipped with a subsurface maneuverable ice melting probe
will be most suitable to assess the existence of life on Enceladus. A lander would have to
land at a safe distance away from a plume source and melt its way to the inner wall of the
fracture to analyze the plume subsurface liquids before potential biosignatures are
degraded or destroyed by exposure to the vacuum of space. A possible approach for the
in situ detection of biosignatures in such samples can be based on the hypothesis of
universal evolutionary convergence, meaning that the independent and repeated emer-
gence of life and certain adaptive traits is wide-spread throughout the cosmos. We thus
present a hypothetical evolutionary trajectory leading towards the emergence of metha-
nogenic chemoautotrophic microorganisms as the baseline for putative biological com-
plexity on Enceladus. To detect their presence, several instruments are proposed that may
be taken aboard a future subglacial melting probe.
The “Enceladus Explorer” (EnEx) project funded by the German Space Administration
(DLR), aims to develop a terrestrial navigation system for a subglacial research probe and
eventually test it under realistic conditions in Antarctica using the EnEx-IceMole, a novel maneuverable subsurface ice melting probe for clean sampling and in situ analysis of ice
and subglacial liquids. As part of the EnEx project, an initial concept study is foreseen for a
lander mission to Enceladus to deploy the IceMole near one of the active water plumes on
the moon's South-Polar Terrain, where it will search for signatures of life.
The general mission concept is to place the Lander at a safe distance from an active
plume. The IceMole would then be deployed to melt its way through the ice crust to an
aquiferous fracture at a depth of 100 m or more for an in situ examination for the presence
of microorganisms.
The driving requirement for the mission is the high energy demand by the IceMole to
melt through the cold Enceladan ices. This requirement is met by a nuclear reactor
providing 5 kW of electrical power. The nuclear reactor and the IceMole are placed on a
pallet lander platform. An Orbiter element is also foreseen, with the main function of
acting as a communications relay between Lander and Earth.
After launch, the Lander and Orbiter will perform the interplanetary transfer to Saturn
together, using the on-board nuclear reactor to power electric thrusters. After Saturn orbit
insertion, the Combined Spacecraft will continue using Nuclear Electric Propulsion to
reach the orbit of Enceladus. After orbit insertion at Enceladus, the Orbiter will perform a
detailed reconnaissance of the South-Polar Terrain. At the end of the reconnaissance
phase, the Lander will separate from the Orbiter and an autonomously guided landing
sequence will place it near one of the active vapor plumes. Once landed, the IceMole will
be deployed and start melting through the ice, while navigating around hazards and
towards a target subglacial aquiferous fracture.
An initial estimation of the mission's cost is given, as well as recommendations on the
further development of enabling technologies. The planetary protection challenges posed
by such a mission are also addressed.},
    note = {},
    institution = {Universität der Bundeswehr München, Fakultät für Luft- und Raumfahrttechnik, LRT 9 - Institut für Raumfahrttechnik und Weltraumnutzung, Professur: Förstner, Roger},
    
    
}