CURRENT PROJECTS
UREY: |
Mars Organic and Oxidant Detector
Searching for Signs of Life on Mars
ESA Pasteur/ExoMars Mission |
Science Team Members:
Jeffrey L. Bada, PI, Scripps Institution of Oceanography, U. C. San Diego
Ron Amundson, University of California, Berkeley
Laurence Barron, University of Glasgow, UK
Diana L. Blaney, Jet Propulsion Laboratory, Cal Tech
Oliver Botta, International Space Science Institute, Bern, Switzerland
Benton Clark, Lockheed Martin, Denver
Max Coleman, Jet Propulsion Laboratory, Cal Tech
Pascale Ehrenfreund, Astrobiology, Leiden University, The Netherlands
Daniel Glavin, NASA Goddard Space Flight Center
Frank Grunthaner, Jet Propulsion Laboratory, Cal Tech
Beda Hoffman, Natural History Museum, Bern
Jean-Luc Josset, Space Exploration Institute, Switzerland
Richard A. Mathies, University of California, Berkeley
Richard Quinn, SETI Institute
Petra Rettberg, German Aerospace Center, Koln, Germany
Francois Robert, Natural Museum of History, Paris
Mark Sephton, Imperial College, London
Albert Yen, Jet Propulsion Laboratory, Cal Tech
Aaron Zent, NASA Ames Research Center
On Monday, Jan. 8, 2007, NASA announced its decision to fund the Urey instrument at an initial level of $750,000 for a technology development study. Urey was judged as having the best science value among 26 proposals submitted to NASA in August 2006 in response to an open announcement of opportunity.
NASA selected UREY for technology development studies to enhance its capabilities as a contribution to the ESA ExoMars Mission. Urey has already been selected by ESA as a component of the ExoMars Mission scheduled for 2013. This receipt of funds for additional technical development from NASA is an important step toward the development of a flight instrument. The Urey instrument would investigate organics and oxidant materials on Mars using three
complementary detection systems.
"These mission selections represent unprecedented future research that will lead to further advancing our knowledge and understanding of the Red Planet's climate, and atmospheric composition," said Mary Cleave, associate administrator for NASA's Science Mission Directorate, NASA Headquarters, Washington.
ABSTRACT
The UREY Instrument is designed to carry out a series of in situ experiments on Mars as a part of the rover package on the ESA ExoMars-Pasteur Mission which is scheduled for launch in 2013. The instrument suite is named for Professor Urey in recognition of the landmark Miller-Urey experiment that first showed amino acids could be made via abiotic processes as well as Urey’s insights into the origin of the solar system. UREY consists of four components: a subcritical water extractor (SCWE) and a sublimation apparatus called the Mars Organic Detector (MOD) for isolation and concentration of organic biomarkers; a novel lab-on-a-chip microcapillary electrophoresis (CE) system for composition and chirality analysis; and the Mars Oxidant Instrument (MOI). The SCWE is used to extract the target compounds from samples. MOD next uses sublimation to purify and concentrate the target organic compounds. The presence of the target organic compounds is determined by measuring the fluorescence on a MOD sublimation capture cold finger. In the case of amino acids, amines and nucleobases, fluorescence is generated by their reaction with the fluorogenic dye fluorescamine. Sublimed PAH’s are naturally fluorescent and can be detected directly and analyzed with a fluorescence spectrograph. When an amine/amino acid signal is detected, the microchip based CE separation device with integrated reaction chambers, pumps, and a capillary sipper is used to gather the sublimate from the fluorescamine coated portion of the cold finger and determine amino acid composition and chirality in order to evaluate their origin. The observation of nonracemic amino acids would suggest the presence of life based on peptide polymers. The combined system has been field tested in the Atacama Desert, Chile and shown to provide part-per-billion to part-per-trillion sensitivity for amino acids, amines and nucleobases. The SCWE/MOD/CE suite is combined with the MOI component that is used to determine oxidative characteristics of the samples in order to provide data on the role of oxidation reactions on the survival of organic compounds in the Martian regolith. UREY is a powerful suite of instruments designed to sensitively look for the presence of extinct or extant life on Mars.
UREY IN MORE DETAIL
The UREY Instrument is designed to carry out a series of in situ experiments on Mars as a part of the rover package on the ESA ExoMars-Pasteur Mission which is scheduled for launch in 2013. The instrument suite is named for Professor Urey in recognition of the landmark Miller-Urey experiment that first showed amino acids could be made via abiotic processes as well as Urey’s insights into the origin of the solar system. UREY consists of four components: a subcritical water extractor (SCWE) and a sublimation apparatus called the Mars Organic Detector (MOD) for isolation and concentration of organic biomarkers; a novel lab-on-a-chip microcapillary electrophoresis (CE) system for composition and chirality analysis; and the Mars Oxidant Instrument (MOI). The SCWE is used to extract the target compounds from samples. MOD next uses sublimation to purify and concentrate the target organic compounds. The presence of the target organic compounds is determined by measuring the fluorescence on a MOD sublimation capture cold finger. In the case of amino acids, amines and nucleobases, fluorescence is generated by their reaction with the fluorogenic dye fluorescamine. Sublimed PAH’s are naturally fluorescent and can be detected directly and analyzed with a fluorescence spectrograph. When an amine/amino acid signal is detected, the microchip based CE separation device with integrated reaction chambers, pumps, and a capillary sipper is used to gather the sublimate from the fluorescamine coated portion of the cold finger and determine amino acid composition and chirality in order to evaluate their origin. The observation of nonracemic amino acids would suggest the presence of life based on peptide polymers. The combined system has been field tested in the Atacama Desert, Chile and shown to provide part-per-billion to part-per-trillion sensitivity for amino acids, amines and nucleobases. The SCWE/MOD/CE suite is combined with the MOI component that is used to determine oxidative characteristics of the samples in order to provide data on the role of oxidation reactions on the survival of organic compounds in the Martian regolith. UREY is a powerful suite of instruments designed to sensitively look for the presence of extinct or extant life on Mars.
Science Investigation
Urey: Mars Organic and Oxidant Detector, has been selected for the Pasteur payload in the European Space Agency’s (ESA’s) ExoMars rover mission and is considered a fundamental instrument to achieve the mission’s scientific objectives. Urey will perform a groundbreaking investigation of the Martian environment that will involve searching for organic compounds indicative of life and prebiotic chemistry at a sensitivity many orders of magnitude greater than Viking or other insitu organic detection systems. Urey will perform the first insitu search for key classes of organic molecules using state-of-the-art analytical methods that provide part-per-trillion sensitivity. It will ascertain whether any of these molecules are abiotic or biotic in orgin and will evaluate the survival potential of organic compounds in the environment using state-of-the-art chemoresistor oxidant sensors.
Overview
The National Research Council (NRC) report, New Frontiers in the Solar System: An Integrated Exploration Strategy, states that the three key questions “for a paradigm-altering discovery” are:
• Does life currently exist on Mars?
• Did life ever exist there?
• How hospitable was and is Mars to life?
These questions form the basis for the primary goal of the Pasteur Instrument payload on
ESA’s ExoMars mission: “To search for signs of past and present life.”
Urey addresses each of the NRC report questions, as well as the Pasteur instrument payload’s primary goal, in a robust and comprehensive manner. Specifically, Urey
investigates the following hypotheses:
• Are organic compounds with a primary amino group (amino acids, amines,
nucleobases, amino sugars) and polycyclic aromatic hydrocarbons (PAHs)—our target
compounds—derived from either extinct or extant life and/or abiotic sources, detectable
in the regolith of Mars?
• Using compositional and chirality characteristics of detected amino acids, can
we determine whether they are of biotic or abiotic origin?
• Are organic compounds degraded in near-surface environments on Mars via an array
of photolytic and heterogeneous chemical processes, and are these processes a central
factor in determining the abundance and type of our target compounds in the Mars
regolith?
To test these hypotheses, Urey carries out two complementary experiments:
1. Urey uses a Sub-Critical Water Extractor (SCWE), the Mars Organic Detector
(MOD), and a Micro-Capillary Electrophoresis (μCE) analyzer to investigate the
target organic compounds in samples collected during the ExoMars rover activities.
Samples will be analyzed to detect the presence of organic compounds—and to determine their composition. If detected, amino acids are analyzed further to determine their chirality.
2. Urey uses a chemometric sensor array, the Mars Oxidant Instrument (MOI), to
measure the reaction rates of films that have different sensitivities to particular types of oxidants expected to be present in the Mars surface environment. By controlling the temperature of these films and their exposure to dust, ultraviolet light and water vapor, Urey will evaluate organic degradation pathways that may take place at sampled localities on Mars. These data will provide important insights into the observed organic matter inventory and the potential for survival of various classes of organic compounds under
Martian environmental conditions.
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The Mars Organic and Oxidant Detector instrument is named Urey in recognition of Harold Clayton Urey’s seminal contributions to cosmochemistry, geochemistry,and the study of the origin of life. The overall goal of Urey is to search for organic compounds directly in the regolith of Mars and to assess their origin. |
Click to see full size PDFs
Hypotheses Linked to UREY Experiments
Schematic of the UREY Instrument
(Please be patient, this is a very large file)
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'New Stratgies to Detect Life on Mars' by Jeffrey Bada et al.
The quest to determine whether life exiseted, or still exists, on Mars continues
with several missions planned for the red planet by both the European Space Agency
(ESA) and the National Aeronautics and Space Administration (NASA) in the next
few decades. One instrument designed for these missions is the Mars Organic
Detector (MOD), which uses a new approach to achieve exceptionally high
detection sensitivities and analysis capabilities for key bio-organic compounds. MOD
is scheduled to fly in the ESA ExoMars mission early next decade and will attempt to
answer the question of whether we are alone in the solar system. Here the MOD team
explains why we have reason to be optimistic about uncovering the organic secrets of Mars. ...more
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Microfabricated Organic Analyzer
for In Situ Exploration of Mars and Other Solar Bodies
A NASA Astrobiology Science and Technology for Exploring Planets (ASTEP) grant
has been awarded to Prof. Mathies, Prof. Bada at Scripps and Dr. Grunthaner
at JPL for a total of $1,820,400 to develop the Microfabricated Organic Analyzer
for In Situ Exploration of Mars and Other Solar Bodies (2/15/04-2/14/07).
Briefly in collaboration with Dr. Jeffrey
Bada (U.C. San Diego) and Dr. Frank Grunthaner (Jet
Propulsion Laboratory) this is a proposal to integrate
and field test the Microfabricated Organic Analyzer,
designed to be deployed on Mars and other planets for
the quantitation and characterization of amino acids
in soil and other samples. The total budget includes
$860,400 for work at JPL, $225,000 for work at UCSD
and $735,000 at UCB over the three year period.
This multi-institutional proposal will integrate a
portable version of the Microfabricated Organic Analyzer
(MOA) and use it to test for key bio-organic marker
compounds in terrestrial sites having chemical and
environmental conditions that model the deployment
of in situ Astrobiology instrumentation on planetary
missions to the Martian surface. The goals of this
project will be (i) to complete the brass-board development
of a novel lab-on-a-chip device for the analysis of
organic amines and for amino acid composition and chirality
analysis, (ii) to couple this microchip analyzer with
the previously developed Mars Organic Detector (MOD)
which will function as the sample acquisition and preparation
unit, and (iii) to perform a series of field campaigns
in the Mojave and in three unique Atacama Desert sites,
with strikingly different water abundances and organic
content, to test and improve this brass-board analysis
system. This project is based on the mature MOD platform
that uses sublimation to purify PAH's, organic amines
and amino acids from soil and other samples. The presence
and concentration of these targets is indicated by
their reaction with a dye, fluorescamine, on a capture
cold-finger followed by fluorescence detection. A microfabricated
capillary electrophoresis (CE) separation device with
reaction chambers, pumps and capillary sipper sample
input is then used to gather the sublimed and labeled
sample from the cold finger followed by CE analysis
to determine the amine composition and amino acid composition
and chirality. This project combines a complementary
suite of in situ instruments with state-of-the-art
organic compound detection to perform organic biomarker
compound characterization. The success of this project
will establish the feasibility of the MOA for Mars
exploration and for the study of other solar system
targets such as Europa. Our specific objectives are
to:
- Document the maturation, integration and field
operation of two in situ MIDP- PIDDP- and ASTID-derived
instruments. (technology thrust).
- Deploy the integrated Microfabricated Organic Analyzer
in Field Campaigns to the Mojave and to the Atacama
Desert with experiments conducted under flight-like
remote operation conditions to enhance the TRL of
the MOA for possible flight opportunities such as
the MSL.
- Increase our understanding of the limits and constraints
of life in extreme environments by comparing Atacama
sites that range from sterile to viable and to develop
a better under-standing of the identity and sensitivity
of potential chemical biomarkers (science thrust).
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Note that in this multilayer structure, red channels
are within the electrophoresis layer, blue channels
are between the electrophoresis layer and the PDMS
membrane, and green channels are in the pneumatic
layer. The instrument will be 4 x 10 x 8" and the
chip is a 100 mm diameter wafer.
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A Microfabricated Bio-organic
Laboratory for In Situ Extraterrestrial Exploration
A NASA Astrobiology Science Technology Instrument Development (ASTID) grant
has been awarded to Prof. Mathies for the period 12/01/03-11/30/06 for the
amount of $569,441 to develop A Microfabricated Bio-organic Laboratory for
In Situ Extraterrestrial Exploration
Briefly the goal of this research is
to develop novel capture matrix-based concentration
and labeling methods and apparatus for automated in
situ analysis of a broad range of bio-organic molecules.
A more detailed statement of our activities is given
below:
Recent advances in the development of
microfabricated lab-on-a-chip analysis systems have
enhanced the feasibility and capabilities of in situ
chemical and biochemical analyzers. While a wide variety
of bio-organic molecules can be probed with such systems,
we focused our initial studies on the development of
an amino acid analyzer with the hypothesis that extraterrestrial
life would be based on homochiral amino acid polymers.
We developed an electrophoresis chip, detection system
and analysis method where the hydrolyzed amino acids
were fluorescently labeled and then analyzed in minutes
via a capillary zone electrophoresis separation in
the presence of g-cyclodextrin as the chiral recognition
agent. We now propose the development of a more general
Microfabricated Bio-organic Laboratory (MBL) that will
analyze samples for a more complete menu of bio-organics
including but not limited to zwitterionic amino acids,
nucleobases, sugars, organic acids and organic bases
using novel capture matrix chemistries coupled with
a second dimension of microchip CE analysis.
The MBL uses microfabricated pumps and
sippers to sample from a source which can be an aqueous
sample stream from a cryobot, an aqueous extract of
solid samples, etc. The sample passes through microfluidic
elements to adjust ionic strength and pH into acceptable
ranges if needed and is then directed to a series of
affinity capture chambers. These capture chambers contain
a polymeric sol-gel modified with group-specific affinity
reagents that will concentrate and purify the sample
by chemical affinity. This process permits the concentration,
purification and stratification of input molecules
from potentially very dilute or dirty inputs. Following
capture, the analytes are released, labeled with a
group-specific reagent, and separated on-chip to produce
a second "spectral" dimension of analysis
that is used for further chemical identification.
The Microfabricated Bio-organic Laboratory
proposed here has several benefits: it will provide
multiparameter analysis for the presence of bio-organics
in extraterrestrial environments thereby more generally
testing for the presence of extant or extinct life.
Second, the broadly based organic analysis capabilities
of the device will make it advantageous for missions
to other extraterrestrial bodies such as asteroids
and Europa. Finally, the small size, low power requirements,
and microfluidic elements of the MBL allow it to be
integrated with a wide variety of exploration platforms
and to operate in low g or low pressure environments.
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A two-stage analysis is performed: samples are
first partitioned by the use of affinity capture
matrices into five groups: amino acids, nucleobases,
sugars, organic acids and organic bases. The second stage of analysis is
performed by releasing the molecules, labeling them with a fluorescent dye
and sending them to a microfabricated separation column for secondary molecular
analysis.
Adapted from Skelley, A. M., Grunthaner,
F. J., Bada, J. L., and Mathies, R. A. Mars Organic
Detector III: A Versatile Instrument for Detection
of Bio-organic Signature on Mars, SPIE - The International
Society for Optical Engineering Proceedings, First
Jet Propulsion Laboratory In Situ Instruments Workshop,
June 11-13, 2002, Pasadena, CA, G. H. Bearman and
P. M. Beauchamp, Editors, Volume 4878, p. 59-67 (2003). Link
to PDF
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