Astrobiology Field Laboratory
Encyclopedia
The Astrobiology Field Laboratory (AFL) (also Mars Astrobiology Field Laboratory or MAFL) was a proposed NASA
unmanned spacecraft that would have conducted a robotic search for life on Mars
. This proposed mission, which was not funded, would have landed a rover
on Mars
and explore a site thought to be a habitat
. Examples of such sites are an active or extinct hydrothermal deposit, a dry lake or a specific polar site.
Had it been funded, the rover was to be built by NASA's Jet Propulsion Laboratory, based upon the Mars Science Laboratory
rover design, it would have carried astrobiology
-oriented instruments, and ideally, a core drill
. The original plans called for a launch in 2016, however, budgetary constraints caused funding cuts.
landers of the 1970s to specifically look for the chemistry associated with life (biosignature
s), such as carbon-based compounds
along with molecules involving both sulfur
and nitrogen
. The mission strategy was to search for habitable zone
s by "following the water" and "finding the carbon." In particular, it was to conduct detailed analysis of geologic environments identified by the 2011 Mars Science Laboratory
as being conducive to life on Mars
and biosignature
s, past and present. Such environments might include fine-grained sedimentary layers, hot spring
mineral deposits, icy layers near the poles, or sites such as gullies where liquid water once flowed or may continue to seep into soils from melting ice packs.
(launched in 2005), Phoenix lander
(launched in 2007), Mars Science Laboratory
(to launch in 2011), the Trace Gas Mission orbiter (to launch in 2016), and the ExoMars
(to launch in 2018) projects in this strategic effort. The AFL 'Science Steering Group' developed the following set of search strategies and assumptions for increasing the likelihood of detecting biosignatures:
rover (the system is known as SAM (Sample Analysis at Mars) in 2011-configuration of Mars Science Laboratory). The AFL payload was to attempt to minimize any conflicting positive detection of life by including a suite of instruments that provide at least three mutually confirming analytical laboratory measurements.
For the purpose of discerning a reasonable estimate on which to base the rover mass, the conceptual payload was to include:
. The radioactive RTG power source was to last for about one Martian year, or approximately two Earth years. RTGs can provide reliable, continuous power day and night, and waste heat can be used via pipes to warm systems, freeing electrical power for the operation of the vehicle and instruments.
Within the region of surface operations, identify and classify Martian environments (past or present) with different habitability potential, and characterize their geologic context. Quantitatively assess habitability potential by:
It is fundamental to the AFL concept to understand that organisms and their environment
constitute a system, within which any one part can affect the other. If life exists or has existed on Mars, scientific measurements to be considered would focus on understanding those systems that support or supported it. If life never existed while conditions were suitable for life formation, understanding why a Martian genesis never occurred would be a future priority. The AFL team stated that it is reasonable to expect that missions like AFL will play a significant role in this process, but unreasonable to expect that they will bring it to a conclusion.
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...
unmanned spacecraft that would have conducted a robotic search for life on Mars
Life on Mars
Scientists have long speculated about the possibility of life on Mars owing to the planet's proximity and similarity to Earth. Fictional Martians have been a recurring feature of popular entertainment of the 20th and 21st centuries, but it remains an open question whether life currently exists on...
. This proposed mission, which was not funded, would have landed a rover
Rover (space exploration)
A rover is a space exploration vehicle designed to move across the surface of a planet or other astronomical body. Some rovers have been designed to transport members of a human spaceflight crew; others have been partially or fully autonomous robots...
on Mars
Mars
Mars is the fourth planet from the Sun in the Solar System. The planet is named after the Roman god of war, Mars. It is often described as the "Red Planet", as the iron oxide prevalent on its surface gives it a reddish appearance...
and explore a site thought to be a habitat
Habitat
* Habitat , a place where a species lives and grows*Human habitat, a place where humans live, work or play** Space habitat, a space station intended as a permanent settlement...
. Examples of such sites are an active or extinct hydrothermal deposit, a dry lake or a specific polar site.
Had it been funded, the rover was to be built by NASA's Jet Propulsion Laboratory, based upon the Mars Science Laboratory
Mars Science Laboratory
The Mars Science Laboratory is a National Aeronautics and Space Administration mission with the aim to land and operate a rover named Curiosity on the surface of Mars. The MSL was launched November 26, 2011, at 10:02 EST and is scheduled to land on Mars at Gale Crater between August 6 and 20, 2012...
rover design, it would have carried astrobiology
Astrobiology
Astrobiology is the study of the origin, evolution, distribution, and future of life in the universe. This interdisciplinary field encompasses the search for habitable environments in our Solar System and habitable planets outside our Solar System, the search for evidence of prebiotic chemistry,...
-oriented instruments, and ideally, a core drill
Core drill
A core drill is a drill specifically designed to remove a cylinder of material, much like a hole saw. The material left inside the drill bit is referred to as the core....
. The original plans called for a launch in 2016, however, budgetary constraints caused funding cuts.
Mission
The rover could have been the first mission since the Viking programViking program
The Viking program consisted of a pair of American space probes sent to Mars, Viking 1 and Viking 2. Each spacecraft was composed of two main parts, an orbiter designed to photograph the surface of Mars from orbit, and a lander designed to study the planet from the surface...
landers of the 1970s to specifically look for the chemistry associated with life (biosignature
Biosignature
A biosignature is any substance -such as an element, isotope, or molecule - or phenomenon that provides scientific evidence of past or present life. Measurable attributes of life include its complex physical and chemical structures and also its utilization of free energy and the production of...
s), such as carbon-based compounds
Carbon-based life
Carbon forms the backbone of biology for all of life on Earth. Complex molecules are made up of carbon bonded with other elements, especially oxygen, hydrogen and nitrogen, and carbon is able to bond with all of these because of its four valence electrons. Carbon is abundant on earth...
along with molecules involving both sulfur
Sulfur
Sulfur or sulphur is the chemical element with atomic number 16. In the periodic table it is represented by the symbol S. It is an abundant, multivalent non-metal. Under normal conditions, sulfur atoms form cyclic octatomic molecules with chemical formula S8. Elemental sulfur is a bright yellow...
and nitrogen
Nitrogen
Nitrogen is a chemical element that has the symbol N, atomic number of 7 and atomic mass 14.00674 u. Elemental nitrogen is a colorless, odorless, tasteless, and mostly inert diatomic gas at standard conditions, constituting 78.08% by volume of Earth's atmosphere...
. The mission strategy was to search for habitable zone
Habitable zone
In astronomy and astrobiology, a habitable zone is an umbrella term for regions that are considered favourable to life. The concept is inferred from the empirical study of conditions favourable for Life on Earth...
s by "following the water" and "finding the carbon." In particular, it was to conduct detailed analysis of geologic environments identified by the 2011 Mars Science Laboratory
Mars Science Laboratory
The Mars Science Laboratory is a National Aeronautics and Space Administration mission with the aim to land and operate a rover named Curiosity on the surface of Mars. The MSL was launched November 26, 2011, at 10:02 EST and is scheduled to land on Mars at Gale Crater between August 6 and 20, 2012...
as being conducive to life on Mars
Life on Mars
Scientists have long speculated about the possibility of life on Mars owing to the planet's proximity and similarity to Earth. Fictional Martians have been a recurring feature of popular entertainment of the 20th and 21st centuries, but it remains an open question whether life currently exists on...
and biosignature
Biosignature
A biosignature is any substance -such as an element, isotope, or molecule - or phenomenon that provides scientific evidence of past or present life. Measurable attributes of life include its complex physical and chemical structures and also its utilization of free energy and the production of...
s, past and present. Such environments might include fine-grained sedimentary layers, hot spring
Hot spring
A hot spring is a spring that is produced by the emergence of geothermally heated groundwater from the Earth's crust. There are geothermal hot springs in many locations all over the crust of the earth.-Definitions:...
mineral deposits, icy layers near the poles, or sites such as gullies where liquid water once flowed or may continue to seep into soils from melting ice packs.
Planning
The Astrobiology Field Laboratory (AFL) would have followed the Mars Reconnaissance OrbiterMars Reconnaissance Orbiter
Mars Reconnaissance Orbiter is a NASA multipurpose spacecraft designed to conduct reconnaissance and Exploration of Mars from orbit...
(launched in 2005), Phoenix lander
Phoenix (spacecraft)
Phoenix was a robotic spacecraft on a space exploration mission on Mars under the Mars Scout Program. The Phoenix lander descended on Mars on May 25, 2008...
(launched in 2007), Mars Science Laboratory
Mars Science Laboratory
The Mars Science Laboratory is a National Aeronautics and Space Administration mission with the aim to land and operate a rover named Curiosity on the surface of Mars. The MSL was launched November 26, 2011, at 10:02 EST and is scheduled to land on Mars at Gale Crater between August 6 and 20, 2012...
(to launch in 2011), the Trace Gas Mission orbiter (to launch in 2016), and the ExoMars
ExoMars
ExoMars is a European-led robotic mission to Mars currently under development by the European Space Agency with collaboration by NASA...
(to launch in 2018) projects in this strategic effort. The AFL 'Science Steering Group' developed the following set of search strategies and assumptions for increasing the likelihood of detecting biosignatures:
- Life processes may produce a range of biosignatureBiosignatureA biosignature is any substance -such as an element, isotope, or molecule - or phenomenon that provides scientific evidence of past or present life. Measurable attributes of life include its complex physical and chemical structures and also its utilization of free energy and the production of...
s such as lipidLipidLipids constitute a broad group of naturally occurring molecules that include fats, waxes, sterols, fat-soluble vitamins , monoglycerides, diglycerides, triglycerides, phospholipids, and others...
s, proteinProteinProteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...
s, amino acidAmino acidAmino acids are molecules containing an amine group, a carboxylic acid group and a side-chain that varies between different amino acids. The key elements of an amino acid are carbon, hydrogen, oxygen, and nitrogen...
s, kerogenKerogenKerogen is a mixture of organic chemical compounds that make up a portion of the organic matter in sedimentary rocks. It is insoluble in normal organic solvents because of the huge molecular weight of its component compounds. The soluble portion is known as bitumen. When heated to the right...
-like material or characteristic micropores in rock. However, the biosignatures themselves may become progressively destroyed by ongoing environmental processes. - Sample acquisition will need to be executed in multiple locations and at depths below that point on the Martian surface where oxidationRedoxRedox reactions describe all chemical reactions in which atoms have their oxidation state changed....
results in chemical alteration. The surface is oxidizing as a consequence of the absence of magnetic field or magnetosphereMagnetosphereA magnetosphere is formed when a stream of charged particles, such as the solar wind, interacts with and is deflected by the intrinsic magnetic field of a planet or similar body. Earth is surrounded by a magnetosphere, as are the other planets with intrinsic magnetic fields: Mercury, Jupiter,...
shielding from harmful space radiation and solar electromagnetic radiationElectromagnetic radiationElectromagnetic radiation is a form of energy that exhibits wave-like behavior as it travels through space...
—which may well render the surface sterile down to a depth greater than 7.5 metres (24.6 feet). To get under that potential sterile layer, a core drillCore drillA core drill is a drill specifically designed to remove a cylinder of material, much like a hole saw. The material left inside the drill bit is referred to as the core....
design is currently being studied. As with any trade, the inclusion of the drill would come at the mass expense available for other payload elements. - Analytical laboratory biosignature measurements require the pre-selection and identification of high-priority samples, which could be subsequently subsampled to maximize detection probability and spatially resolve potential biosignatureBiosignatureA biosignature is any substance -such as an element, isotope, or molecule - or phenomenon that provides scientific evidence of past or present life. Measurable attributes of life include its complex physical and chemical structures and also its utilization of free energy and the production of...
s for detailed analysis.
Payload
The conceptual payload included a Precision Sample Handling and Processing System to replace and augment the functionality and capabilities provided by the Sample Acquisition Sample Processing and Handling system that is was part of the 2009-configuration of Mars Science LaboratoryMars Science Laboratory
The Mars Science Laboratory is a National Aeronautics and Space Administration mission with the aim to land and operate a rover named Curiosity on the surface of Mars. The MSL was launched November 26, 2011, at 10:02 EST and is scheduled to land on Mars at Gale Crater between August 6 and 20, 2012...
rover (the system is known as SAM (Sample Analysis at Mars) in 2011-configuration of Mars Science Laboratory). The AFL payload was to attempt to minimize any conflicting positive detection of life by including a suite of instruments that provide at least three mutually confirming analytical laboratory measurements.
For the purpose of discerning a reasonable estimate on which to base the rover mass, the conceptual payload was to include:
- Precision Sample Handling and Processing System.
- Forward Planetary Protection for Life-Detection Mission to a Special Region.
- Life Detection-Contamination Avoidance.
- Astrobiology Instrument Development.
- MSL Parachute Enhancement.
- Autonomous safe long-distance travel.
- Autonomous single-cycle instrument placement.
- Pinpoint landing (100–1000 m) (if necessary to reach specific science targets in hazardous regions).
- Mobility for highly sloped terrain 30° (if required to reach science targets).
Power source
It was suggested that the Astrobiology Field Laboratory use radioisotope thermoelectric generators (RTGs) as its power source, like the ones to be used on the Mars Science LaboratoryMars Science Laboratory
The Mars Science Laboratory is a National Aeronautics and Space Administration mission with the aim to land and operate a rover named Curiosity on the surface of Mars. The MSL was launched November 26, 2011, at 10:02 EST and is scheduled to land on Mars at Gale Crater between August 6 and 20, 2012...
. The radioactive RTG power source was to last for about one Martian year, or approximately two Earth years. RTGs can provide reliable, continuous power day and night, and waste heat can be used via pipes to warm systems, freeing electrical power for the operation of the vehicle and instruments.
Science
Though the AFL science justification did not include a pre-definition of potential life forms that might be found on Mars, the following assumptions were made:- LifeLifeLife is a characteristic that distinguishes objects that have signaling and self-sustaining processes from those that do not, either because such functions have ceased , or else because they lack such functions and are classified as inanimate...
utilizes some form of carbonCarbonCarbon is the chemical element with symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds...
. - Life requires an external energy source (sunlight or chemical energyBiochemistryBiochemistry, sometimes called biological chemistry, is the study of chemical processes in living organisms, including, but not limited to, living matter. Biochemistry governs all living organisms and living processes...
) to survive. - Life is packaged in cellular-type compartments (cellsCell (biology)The cell is the basic structural and functional unit of all known living organisms. It is the smallest unit of life that is classified as a living thing, and is often called the building block of life. The Alberts text discusses how the "cellular building blocks" move to shape developing embryos....
). - Life requires liquid water.
Within the region of surface operations, identify and classify Martian environments (past or present) with different habitability potential, and characterize their geologic context. Quantitatively assess habitability potential by:
- Measuring isotopicIsotopeIsotopes are variants of atoms of a particular chemical element, which have differing numbers of neutrons. Atoms of a particular element by definition must contain the same number of protons but may have a distinct number of neutrons which differs from atom to atom, without changing the designation...
, chemicalInorganic chemistryInorganic chemistry is the branch of chemistry concerned with the properties and behavior of inorganic compounds. This field covers all chemical compounds except the myriad organic compounds , which are the subjects of organic chemistry...
, mineralogicalMineralogyMineralogy is the study of chemistry, crystal structure, and physical properties of minerals. Specific studies within mineralogy include the processes of mineral origin and formation, classification of minerals, their geographical distribution, as well as their utilization.-History:Early writing...
, and structural characteristics of samples, including the distribution and molecular complexity of carbon compoundsOrganic compoundAn organic compound is any member of a large class of gaseous, liquid, or solid chemical compounds whose molecules contain carbon. For historical reasons discussed below, a few types of carbon-containing compounds such as carbides, carbonates, simple oxides of carbon, and cyanides, as well as the...
. - Assessing biologically available sources of energyEntropy and lifeResearch concerning the relationship between the thermodynamic quantity entropy and the evolution of life began in around the turn of the 20th century...
, including chemical, thermal and electromagnetic. - Determining the role of water (past or present) in the geological processesGeology of MarsThe geology of Mars is the scientific study of the surface, crust, and interior of the planet Mars. It emphasizes the composition, structure, history, and physical processes that shape the planet. It is fully analogous to the field of terrestrial geology. In planetary science, the term geology is...
at the landing site. - Investigate the factors that will affect the preservation of potential signs of life (past or present) This refers to the potential for a particular biosignature to survive and therefore be detected in a particular habitat. Also, post-collection preservation may be required for later sample retrieval, although that would necessitate a further assessment of precision landing of Mars sample return missionMars Sample Return MissionA Mars sample return mission would be a spaceflight mission to collect rock and dust samples from Mars and to return them to Earth for analysis...
mission. - Investigate the possibility of prebiotic chemistryAbiogenesisAbiogenesis or biopoesis is the study of how biological life arises from inorganic matter through natural processes, and the method by which life on Earth arose...
on Mars, including non-carbon biochemistry. - Document any anomalous features that can be hypothesized as possible Martian biosignatures.
It is fundamental to the AFL concept to understand that organisms and their environment
Environment (biophysical)
The biophysical environment is the combined modeling of the physical environment and the biological life forms within the environment, and includes all variables, parameters as well as conditions and modes inside the Earth's biosphere. The biophysical environment can be divided into two categories:...
constitute a system, within which any one part can affect the other. If life exists or has existed on Mars, scientific measurements to be considered would focus on understanding those systems that support or supported it. If life never existed while conditions were suitable for life formation, understanding why a Martian genesis never occurred would be a future priority. The AFL team stated that it is reasonable to expect that missions like AFL will play a significant role in this process, but unreasonable to expect that they will bring it to a conclusion.
See also
- AstrobiologyAstrobiologyAstrobiology is the study of the origin, evolution, distribution, and future of life in the universe. This interdisciplinary field encompasses the search for habitable environments in our Solar System and habitable planets outside our Solar System, the search for evidence of prebiotic chemistry,...
- ExoMarsExoMarsExoMars is a European-led robotic mission to Mars currently under development by the European Space Agency with collaboration by NASA...
- Exploration of MarsExploration of MarsThe exploration of Mars has been an important part of the space exploration programs of the Soviet Union, the United States, Europe, and Japan. Dozens of robotic spacecraft, including orbiters, landers, and rovers, have been launched toward Mars since the 1960s...
- Life on MarsLife on MarsScientists have long speculated about the possibility of life on Mars owing to the planet's proximity and similarity to Earth. Fictional Martians have been a recurring feature of popular entertainment of the 20th and 21st centuries, but it remains an open question whether life currently exists on...
- Mars Astrobiology Explorer-CacherMars Astrobiology Explorer-CacherThe Mars Astrobiology Explorer-Cacher was a NASA concept for a Mars rover mission, proposed to be launched in 2018 together with the European ExoMars rover...
- Mars Science LaboratoryMars Science LaboratoryThe Mars Science Laboratory is a National Aeronautics and Space Administration mission with the aim to land and operate a rover named Curiosity on the surface of Mars. The MSL was launched November 26, 2011, at 10:02 EST and is scheduled to land on Mars at Gale Crater between August 6 and 20, 2012...
- Viking programViking programThe Viking program consisted of a pair of American space probes sent to Mars, Viking 1 and Viking 2. Each spacecraft was composed of two main parts, an orbiter designed to photograph the surface of Mars from orbit, and a lander designed to study the planet from the surface...