Titan: A World with Rivers, Lakes and Possibly Even Life - Movie Review Example

?Your Full Saturn’s Moon Titan: A World with Rivers, Lakes and Possibly Even Life Titan, is one of Saturn’s satellites. For almost twenty years, the NASA Ames Research Center has sent missions to study the chemical properties of this satellite and attempt to find other life forms in the solar system. This paper talks about the findings of this mission through a lecture conducted by Dr. Chris McKay. The Speaker Dr. Chris McKay is a planetary scientist at the NASA Ames Research Center. Most of his research focuses on the search for life in the solar system and the evolution of the solar system. Dr. McKay’s main research is on explorations in Mars, but he also showed interest in Saturn’s moon, Titan. The Titan Exploration The Hydrogen Flux. Dr. McKay and his team became interested in exploring Titan because of the movement of hydrogen gas into Titan’s atmosphere. The scientists referred to this observation as the hydrogen flux, where hydrogen outside Titan moves down Titan’s atmosphere (thicker than Earth’s atmosphere) and no longer goes out back into the atmosphere as hydrogen. The Purpose of the Titan Exploration. The main purpose of Dr. McKay’s team in sending out explorations to different parts of the universe is to find other evidences of life outside of the Earth. By finding evidences, the scientists believe that it will provide more accurate information that there is life in other parts of the solar system (McKay, 2013). Finding another life form will also provide information on the biochemistry of living things. This new life form having a different or similar biochemistry can be compared to the biochemistry of the life forms of Earth, and a more accurate definition of “alien” life form can be established. This suggests that in terms of biochemistry, an “alien” life form is an organism having a biochemistry that is not present in the established “tree of life”. The source of this “alien” life form will no longer matter, whether it was found on another part of the universe or on Earth (McKay, 2013). Basic Needs of Life. Initial step was to identify the basic needs or essentials to have life. McKay (2013) identified energy, carbon, liquid water and other elements as the four basic needs of life. Energy in the universe is readily available through solar energy as well as chemical energy by dissociation or particular reduction-oxidation (redox) reactions. Other elements are also needed for life such as nitrogen and oxygen. Among these needs, liquid water has proven to be the most difficult to find in other worlds in the solar system. However, compared to Earth, Titan does not have liquid water, instead, it has liquid methane (CH4), which is a greenhouse gas on Earth (McKay, 2013). Planetary scientists have then re-defined the need for liquid water as simply a liquid medium. This is because of the different atmospheric conditions of other worlds in the solar system. Other worlds tend to be hotter or colder, and the atmospheric pressure will also be different and these conditions will affect the physical properties of the compounds or elements that we see on Earth. In terms of temperature, as an example, Earth is approximated to be at +15?C, while Titan is about –180?C, which is obviously very, very much colder than Earth. Having such a low temperature, this implied that the only form of water present in Titan is its water ice or water in the form of solids rocks located in its polar region (McKay, 2013). McKay (2013) emphasized that in order for life to persist or function, there has to be some form of liquid medium present in the organism and in that world. The liquid does not have to be the water that we know on Earth, since the physical properties of the compounds are highly influenced by environmental conditions, as explained earlier. Gathering Evidences. McKay (2013) cited that there are three options by which information outside the universe can be gathered; namely: making it in the lab, identifying and exploring a target location and just waiting for another life form to make a call to the Earth. Among the three, the first two options are the more scientific in approach. However, simulation in the laboratory is quite limited because there is still a very huge lack of information so the conditions will still be all theoretical. Exploration, still, proves to be the most logical tool in getting information since these will serve as data that can be studied further until more information is collected. A comparison of Titan and Earth was presented and there were six properties with which these two were compared. In terms of the gravitational pull, Earth was 1, and Titan was 1/7, which does not seem to be a very significant difference. The atmospheric pressure was also compared, with Earth having 1 atmosphere (atm) and Titan at 1.5 atm. The pressure of 1.5 atm is similar to staying underwater at about 15 feet. The atmosphere on Earth is made up of Nitrogen (N2), Oxygen (O2) and Carbon Dioxide (CO2), while that on Titan is N2 and CH4. Precipitates, in the form of clouds, was also compared, with Earth having mostly water, in contrast to Titan’s clouds composed of CH4 and ethylene (C2H4). Greenhouse gases in Titan are composed of N2, CH4 and H2, while Earth is mainly CO2 and water. Temperature was also compared, as previously mentioned, and showed the very low temperature of Titan’s surface (McKay, 2013). Through this comparison, it is quite obvious that Titan does not have an abundance of oxygen compared to Earth. The exploration called the Cassini mission was sent to Titan with the Cassini orbiter taking images outside Titan’s surface and the Huygens’ probe was used to gather information on the organic composition of Titan’s surface. McKay and his team initially expected that Titan’s surface is composed of liquid methane based on some of the images that they have studied prior to the exploration. The probe was then designed similar to a boat based on this assumption. However, when the probe landed at the equatorial region, the information obtained was that it was not an ocean of liquid methane, nor was it a solid rock formation. The closest representation McKay could give was a muddy puddle, which is wet or damp, but not completely dry. The actual image shown by the Huygens’ probe looked like a desert, barren and with rocks everywhere, about up to 15 centimeters in size. The probe was able to indicate that the location was a bit wet and there was CH4 gas detected because the probe was hotter than Titan’s surface when it landed. On the other hand, images from the Cassini orbiter showed lakes and cloud formations at the polar regions of Titan (McKay, 2013). From the images of the Cassini orbiter and the information taken from Huygens’ probe, it was established that Titan has lakes in its polar regions and the equatorial regions were similar to Earth’s deserts, but with moist soil (McKay, 2013). Theoretical Life Form in Titan. With the establishment of the chemical components in Titan’s surface and atmosphere, scientists have provided some ways in which a theoretical life form in Titan will feed or derive its energy from. This feeding or consumption was only focused on the chemical reactions, particularly, redox reactions of organic compounds that will create methane as its product together with energy. From the different compounds, acetylene (C2H2) proved to be the best source of energy, at about 80 kcal/mol, and yielding CH4 as one of its products from the redox reaction. Another possible source is ethane undergoing the same hydrogenation process (McKay, 2013). With the abundance of hydrogen inside Titan’s atmosphere, it can be expected that the hydrogenation process will almost occur spontaneously. Challenges of Life in Titan. McKay (2013) also stated the condition that the theoretical life forms will have to deal with to be able to survive in Titan. There is great emphasis that life requires oxygen in order for certain processes to occur. Or those that cannot use oxygen to live evolved into organisms capable to survive in anaerobic conditions, as the case of nitrogen-fixing bacteria. With this requirement for life, the only possible source of oxygen in Titan is the water ice which, has yet to undergo different physical and chemical changes to be able to free the oxygen and be available for use in biological functions. Another condition with which a possible life form would have to deal with is the temperature in Titan. This kind of temperature will create very slow metabolism for the theoretical life form, unless it evolves or mutates to adapt to the current condition in Titan. Such life forms capable of mutating are expected to be only at the cellular or prebiotic levels (McKay, 2013). NASA’s Challenges. The Titan exploration is challenging for NASA in terms of the technology used to be able to gather information about Titan’s atmosphere. Data interpretation and evaluation is easier, compared to the required steps and techniques that have to be done to be able to generate reliable information. The limitation that Titan is very distant from the Earth poses the greatest challenges, suggesting that state-of-the-art engineering is important to be able to send out missions that will be less costly and more time efficient. The GC/MS is an important tool to be able to identify the chemicals collected on-site, but the limitation is that they have to be in vapor form. The water ice samples can then be not collected because there is no container available yet that can preserve the solid samples and bring it back to Earth as its natural form in Titan without causing any contamination or loss of sample integrity (McKay, 2013). The design of the space craft carrying the necessary instruments is also a challenge for NASA. McKay (2013) emphasized the difficulty in getting the equipments to Titan and being able to analyze the samples immediately. This will include challenges in maneuvering the probe from the surface and getting it back to where the samples will be analyzed, and subjecting the samples to different kinds of extraction and preparation before it can be analyzed using equipments like GC/MS or other analytical tools. This obviously requires the intervention of robotics, since human exploration to Titan will be even more difficult. Discussion The lecture was very informative and made me recall the periodic table of elements during the discussion. Basic organic chemistry and biochemistry also came to mind while watching the lecture. The information being delivered by Dr. Chris McKay was very basic and expressed in a language understandable by ordinary people, and not requiring sophisticated knowledge of astronomy or engineering. The speaker was able to dictate the flow of the lecture and helped the audience visualize the initial standpoint for the discussion. Although the topic was very scientific in context, the speaker was still able to put some humor into the lecture and provide a more relaxed ambiance. I also found myself smiling or giggling on his remarks about the tricorder and the emphasis on the “scientific” differences between a thud, a splash and a splat. There were some parts of the discussion that also raised my interest, like the report on what Dr. McKay referred to as the “missing hydrogen”. The single, irreversible movement of hydrogen from Titan’s atmosphere to its surface is very puzzling; however, the hypothesis that there may be some form of life that sucks all the hydrogen and uses it to survive is not fully agreeable. This kind of hypothesis appears to be too optimistic given the atmospheric conditions in Titan, where the temperature is so low and the gas compositions are almost in a flammable state, knowing that methane and hydrogen are flammable gases. This is like having an enclosure filled with natural gas. But again, combustion requires the presence of oxygen in order to occur. Fortunately, oxygen in Titan is frozen in the form of water ice and this prevents the combustion process. This is probably as analogous as nitrogen’s composition on the Earth’s atmosphere to prevent spontaneous combustion with the abundance of oxygen. Another perspective that can be considered may be the existence of an element or compound in Titan’s surface that uses hydrogen from the atmosphere and causes a redox reaction in the surface. There has not been any exploration that aimed to determine the depth of Titan’s surface, or the composition underneath the crust of Titan. McKay was not able to give information about Titan’s subsurface, so this implies that the compounds underneath the methane surface layer has not been explored, and the possible answer to the missing hydrogen case may be found under Titan’s surface. So it is not just the possibility of life, but just a possibility of the existence of a different form of element or compound. The concept of a liquid medium as the fundamental of life is agreeable, since almost all living things on earth have some sort of liquid in their cells to be able to function. If this will again be compared to Titan, the atmospheric conditions will have to be considered. I found myself imagining the periodic table and wondering what element or compound will be liquid in Titan, and at the same time, be vital in maintaining cellular functions. This can only be answered if further study on elements and compounds is done at the same condition as in Titan, which is at 1.5 atm and –180?C. Although methane was proven to be very abundant in Titan’s surface, there may be other types of compounds in Titan behaving similarly as methane. Such experiments are expected to be costly and will require a lot of time to generate acceptable results. McKay’s presentation on the possible consumption of acetylene and ethane by theoretical Titan life forms is not convincing. It was presented that the atmosphere of Titan was rich in N2 and CH4, but there was no information given indicating the presence of acetylene. Either the hypothesis was formulated after they were able to figure out that CH4 was the main gas present in Titan, or there was no test conducted to determine the presence of acetylene. Probably if there will be another Titan exploration to be sent out, this hypothesis can be proven if a more detailed analysis of Titan’s atmosphere can be done. During the discussion, McKay did not emphasize the duration of the Titan mission. At first, the exploration seemed to be easy with just the technology and maneuvering challenges being recognized, but it was not until the open forum that the twenty-year duration was brought out, which made the Titan exploration suddenly appear vague. As an audience, hearing about this kind of issue, I ended up wondering who would want to invest in such exploration or will NASA continue to pursue the Titan mission? I completely agree with McKay’s view of how difficult and challenging the Titan exploration would be. Obviously, state-of-the-art engineering technology and robotics come into the picture. Humans cannot seem to be directly involved in the Titan exploration itself because of the very long duration of travel from Earth to Titan and back. It appears that the travel time is longer compared to the actual sample and data collection. And McKay (2013) mentioning that it took twenty years to complete a single Titan exploration magnifies the difficulty faced by NASA. Given the twenty years required for one mission, a lot of issues will have to be dealt with if there will be a hands-on participation of human beings in the Titan exploration. It will be even harder to find people willing to spend twenty years of their lives in outer space. Involvement of robotics and design is one difficult issue, and an option of sending a team of astronauts to Titan is a different issue. Although McKay never mentioned of any intent of NASA to send out human beings to Titan, probably the second option seems to be more efficient, given that there will only be instructions that have to be followed compared to robots that have to be properly calibrated and maneuvered in order to simulate an actual human conducting the analysis on-site at Titan’s surface. But it will again go back to issues on safety, cost, efficiency and accuracy of results. I believe as much as possible and if circumstances allow, NASA would prefer sending out explorations without having to risk human lives, or even other forms of animal life just to get the information they want. These issues have to be properly assessed and the next steps to Titan exploration have to be more precise by using the data they have gathered. Conclusion The NASA Ames Research Center believes that Titan has to be explored because of its similarities with Earth and the assumption of the possibility of life, as this will provide science with more evidence of life in other parts of the solar system and will also create further curiosity on possible life outside Earth’s galaxy. Based on the lecture conducted by Dr. Chris McKay, this exploration appears too ambitious to still be continued. Although the challenges and difficulties which NASA faced were cited, and this project being on fourth priority clearly implies that NASA aims to keep working on this project. The whole Titan exploration is a lot of hard work and a lot of time of different scientists has been spent on this mission, even if the information that was gathered is significant, an ordinary person would probably ask if it is worth all the sacrifices that have to be made to be able to make this mission work. There is no doubt that NASA aims to continuously provide accurate information of the universe and its technology is agreeably beyond contest. However, with the issues faced with their aim to dig deeper into Titan’s surface and find a possible form of life has more disadvantages and requires too much effort that it seems to be more beneficial to abort this mission completely and deal with seeking information that is more significant to people on Earth. Failing to know everything about Titan and more generally the universe would not make NASA less of what it has established at present, for it has already stretched our knowledge of the solar system farther than what humans have learned in the past. Works Cited McKay, Chris. “Saturn’s Moon Titan: A World of Rivers, Lakes and Possibly Even Life”. Foothill College, Los Altos Hills, CA. YouTube. 25 Feb 2013. Web. Read More