How Does Life Begin and Develop?
Objective
1
Sources of 0rganics on Earth
Objective
2
Origin of Life's Cellular Components
Objective
4
Genomic Clues to Evolution
Objective
5
Linking Planetary and Biological Evolution
Does Life Exist Elsewhere in the Universe?
Objective
7
The Extremes of Life
Objective
8
Past and Present Life on Mars
Objective
9
Life's Precursors and Habitats in the Outer Solar System
Objective
10
Natural Migration of Life
Objective
11
Origin of Habitable Planets
Objective
12
Effects of Climate and Geology on Habitability
Objective
13
Extrasolar Biomarkers
What is Life's Future on Earth
and Beyond?
Objective
14
Ecosystem Response to Rapid Environmental Change
Objective
15
Earth's Future Habitability
Objective
16
Bringing Life with Us beyond Earth
Objective
17
Planetary Protection
Question: Does Life Exist Elsewhere in the Universe?
Life's
Precursors and Habitats in the Outer Solar System
Objective 9: Determine the presence of life's chemical precursors and potential habitats for life in the outer solar system.
Recent tantalizing evidence for the possible presence of subsurface liquid water on Europa and other Solar System bodies has extended the search space for life to the outer Solar System. A first step in this search, as with Mars exploration, is to determine the spatial and temporal distribution of liquid water in our Solar System. The discovery of organic or other prebiotic substances on these bodies may shed light on both the origin of these materials and the chemical processes that determine(d) their composition. For example, we might establish whether prebiotic substances came from the infall of primitive exogenous debris, or from aqueous chemical transformations within Europa itself. This knowledge will help us understand the relevance of such chemistry to prebiotic processes and/or life itself, either Earth-based or extraterrestrial. Finally, observations of Titan -- and lesser bodies such as comets and asteroids -- will shed light on the complexity and prebiotic relevance of organic chemical reactions that occurred in those bodies.
Implementation
Near- to mid-term:
- Determine the organic and biogenic
element composition of the gas, ice particles, dust and smaller bodies
(eg. comets and asteroids).
- Develop orbital flight experiments
to determine the inventory of organic compounds and biogenic elements
on Europa's surface.
- Map the thickness of the surface
ice and search for evidence of liquid water on Europa.
- Initiate technology development for in-situ and/or sample return analysis of surface material on Europa associated with dark (linear, etc.) surface features.
Future extensions:
- Explore further for evidence
of habitable conditions and/or life on Europa and other outer planet
satellites. Analyze, in situ and on returned samples, organic material
from the youngest units on Europa for biogenic origin. Initiate technology
development for exploration of the purported subsurface ocean on Europa,
searching for signs of life.
- Develop technology for performing chemical analyses of comets, asteroids and other small objects to determine their prebiotic relevance.