Humans constitute the highly evolved creatures in the universe. They have acquired the natural bent of exploring every corner of the earth and every area they encounter in their daily lives. This habit had contributed many advancements in science, especially. As a result, humans started to explore an area beyond their normal reach. Such area is astrobiology. Astrobiology deals with studying of the origin, spread , evolving trends and life in the future in the universe and Earth as well. It employs the methods from astronomy, chemistry, and biology (Astrobiology, 2014).
Briefly, earlier in 1953, researchers at the University of Chicago, performed a small experiment where they were successful in developing certain substances which the scientists regard as the building blocks of life (Hubbard,2008). Later, in 1959,US NASA started its exobiology project where an instrument was devised to identify if extraterrestrial environment supports microbial life. NASA further expanded exobiology program with better infrastructure and personnel which laid the foundation for today’s astrobiology . Gradually by 1970’s and later, NASA activities gained momentum, led to the funding of various exobiology investigations (Hubbard,2008). Say, in 1990s, attention on astrobiology grew further when the space missions yielded several results. In 1995, researchers found a sun-like star being orbited by extrasolar planet. In 1996, NASA scientist reported about the feasible life signs in a Martian meteorite.
It demonstrated an indication on the existence of organisms that look like bacteria and also represent primitive microscopic fossils. Similarly, Galileo spacecraft of NASA reported images of Jovian moon Europa. Here the evidence was the presence of floating ice rafts on a liquid ocean. In September 1996, NASAs first Astrobiology Workshop attracted nearly 250 professionals from space, and life science fields from various nations (Hubbard,2008).
NASA’s trials on space mission/ astrobiology led to the development of roadmaps that aid in guiding research and technology. In fact, such roadmaps appear to be contributed by various technology experts, researchers. from universities, private and government institutions. The road maps answer queries such as how life began and evolved? Does life exist at any other part of universe, and how the life on earth in future and later? (Des Marais et al., 2003)
In addition, various objectives appear to form an outline for the important areas of research. These are
a) Developing awareness of the nature and spread of habitable environments in the universe
b) Searching for the habitable atmosphere and life in the solar system where we live
c) Developing awareness on the life and its emergence
d) Evaluating how earliest the Earth developed interactions and began to evolve with its varying
atmosphere/climate.
e) Developing awareness about the mechanisms related to evolution and environmental restrictions of life.
f) Evaluating the postulates that will change the future life aspects, and
g) Identifying the signs of life on primitive Earth and on other worlds (Des Marais et al., 2003).
These objectives could have necessitated many efforts since the time they were introduced till date.
One of the key areas in astrobiology is the about the Raman spectroscopy. Scientists consider it as a most indispensible tool for exploring planets as its very sensitive to inorganic and organic substances.
It also clearly recognizes spectral markers when presented in a blend of geological and biological components. So, both NASA and ESA have drawn their attention on adopting Raman spectrometers for incorporating in specific chambers of analytical instruments. These are in turn deposited on robotic landers on the planet, for example Mars (Jorge Villar & , Edwards, 2006). Some investigators have shed light on the habitability.
Heller et al ( 2014) report that moons in the Solar System are unique in thier diversity and quantity which indicates the existence of multiple natural satellites surrounding extrasolar planets. Most importantly, the proportion of sizable moons in the stellar habitable zones appear to exceed that of planets in the circumstellar zones. Due to technological advancements that enabled the recognition of sub-Earth-sized extrasolar planets, initial identification of extrasolar moon has become possible. This could provide some clues on the habitability.
Here, the evolution of exmoon was reported to be under the control of orbital effects. So, this could help in refining techniques that support explorations on exomoon. Scientists mention that natural satellites that have 0.1-0.5 earth mass area) strongly habitable, b)could develop within the circumplanetary debris (iii) are identifiable with the existing technical methods (Heller et al., 2014).
There are many opinions of scientists on the key biological and physical aspects that must be considered while choosing exomoon habitability. Some report that the satellites of jovian planets of 47 Ursae Majoris and 16 Cygni might provide habitats as they orbit their host star at the outer border of the habitable area (Heller and Barnes, 2013).
Further, it was reported that benchtop instruments could recognize biomolecules that colonize extremophilic rocks (Vitek et al., 2012). These biomolecules serve as model terrestrial organisms identical to those that could have been existed on Mars. Earlier, researchers have recognized pure biomolecules that exist at high altitudes and low a mountain zones .This provided the ability of the instruements to function under much intense , terrestrial extreme conditions terrestrially. However, certain queries still remain unresolved. These are that what would be the ability of miniaturized Raman system to identify the key sigs of bimolecular life distributed in rocks? (Vitek et al., 2012).
So, a project could be designed to identify certain pigments linked with endolithic cyanobacteria with novel approaches. The objective is to find if the observed samples provide some clues for the search of life on the planet, Mars (Vitek et al., 2012).
A team of three astrobiology researchers will collect endolithic cyanobacteria that colonize halite samples. For collection, they will visit, Atacama Desert’s Yungay hyperarid zone.
The halite pinnacle will be broken to observe the interior zones of endolithic colonization.
The sample possess three vital zones. The first one is surface itself and shallow subsurface, with much colored black and the inner colonization colored gray. The second one interior zone with gray color and with moderate intensity of pigmentation. The coloration from gray to black indicate the presence of scytonemin pigment.
The third sample will be another interior zone with green color (Vitek et al., 2012).
Initially, all the three zones will be analyzed, without pretreatment procedures. Then, the stone parts that have the zones of cyanobacterial colonization will be set apart (Vitek et al., 2012). The parts will be then grounded, and homogenized. The powder with the flattened surface will be analysed at chosen regions. Later, the samples will be applied for the ExoMars mission. Here, they will be subjected to Raman spectroscopic analysis as a initial screening test for detecting powdered rock samples. For detecting the efficiency of instruments two types of raman spectrometers will be used. They are Rock Hound and Advantage. The instruments will use specific excitation, say 480 to 800nm wavelength to analyze the powdered samples. The expected outcome is the detection of pigments at a specific excitation due to the high intensity and specificity in the powdered samples presented in bulk form. The excitations of instruments will be compared (Vitek et al., 2012).The excitation that proves to be more sensitive for detecting the pigment say, scytonemin will be considered and employed for future trials.
References
Astrobiology. (2014). Retrieved http://www.yourdictionary.com/astrobiology
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Hubbard, S.G.(2008). Astrobiology: Its Origins and Development Retrieved
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Heller, R. & Barnes, R. (2013). Exomoon Habitability Constrained by Illumination and Tidal
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Heller, R., Williams, D., Kipping, D., Limbach ,M.A., Turner, E., Greenberg, R., Sasaki, T.,
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Vitek,P., Jehlička,J., Edwards,H.G.M., Hutchinson, I., Ascaso,C. & Wierzchos, J. (2012).
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