The Possibility of Life on Europa - Term Paper Example

Name: Topic: Lander project Institution: Date of submission: Instructor: Lander project Science aims and strategy For many decades, scientists have embarked on searching for other locations other than the earth that could possibly host extraterrestrial life. Until the 1970s, life was believed to be utterly dependent on solar energy direct from the sun. This paper aims at discovering the possibility of life on Europa, the sixth moon of Jupiter. The paper will entail determining the global and regional context for Europa. It also plans an unmanned landing mission on Europa that will seek to explore its topography and geology including presence of ice and ridges among other things. According to Massachusetts Institute of Technology et al (2013, p. 10) Europa is one the most interesting objects found in the solar systems due to its strong possibility of hosting an ocean of water . The water often get warmed up by tidal heating that occurs beneath its ice-covered surface. As a result, for many hundreds of years, Jupiter’s largest icy moon Europa has drawn of high interest to a number of planetary scientists and astronomers since its first imagery in the 1970s. I believe that Europa, unlike other moons is a moon with a difference. It has a unique surface topography that is smooth and bright like no known moon. When compared to other moons, it relatively lacks significant impact craters often found on its neighboring moons such as Ganymede and Callisto. With this in mind, I cannot wait to launch a mission on Europa that will help us discover more other interesting things found on its surface (Hayden et al., 2013, p. 100). Studies show that the ice shell of Europa is pitted with a number of prominent crisscrossing physical features namely; lineae, domes, albedo and ridges. It is also evident that Jupiter as well as its extensive family including Europa, orbits around the sun as their main source of energy at relatively 5 Astronomical Units (AU). This is a distance at which light from the nearest star travels on earth and seen as faint and weak and the earth temperatures are below freezing point (Coustenis & Encrenaz, 2013, p. 66). Evidence of life Scientist believes that Europa can host life since it harbors an ocean of salty liquid water that exists hundred kilometers deep. It is believed the internal heat created by Europa’s rapid movements around Jupiter warms up this ocean located beneath the moon often. Europa also generates more heat from the gravitational interaction that exists between its Laplace resonance moons such Ganymede and Lo. These movements make Europa heat up, causing Europa’s icy crust to turn into liquids under the surface. Water is an essential requirement for life. Therefore, if there are lakes and oceans of liquid water on its surface, then there may be life. Europa also receives a relative amount of energy from the sun, and solar energy is an essential prerequisite for life. Observation of the surface of Europa further shows that subduction of radiolytically engendered oxidizing species could possibly lead to the generation of free oxygen concentrations similar to those found in terrestrial deep oceans (Belbruno, 2013, p. 35-36). What is the probability of occurrence of ancient or extant life? From the images taken by Galileo, Europa appears like a broken glass with a surface covered with ice. The strong tidal movements could cause the ice melt beneath the ice. Thus, any organic compounds could remain mobile, in water where they could interact to remain alive. Furthermore, scientists argue that life can still exist without being entirely sun-dependent. They state that both water and some solar energy can sustain life in an ecosystem. Therefore, both worms and eukaryotic organisms that indirectly depend on photosynthesis, Achaea, as well as anaerobic chemosynthetic bacteria that often inhabit such ecosystems offer a possible source of life in Europa’s ocean. Life on Europa may exist around the hydrothermal vents much like the algae in the earth’s polar surface. The bacteria and algae could also float around freely in Europa’s waters surfaces. In 2OO9, Richard Greenberg, famous planetary scientist found that the cosmic rays often affecting Europa’s surface tend to convert some existing surface icy water into some free oxygen that is absorbed into the ocean. Within a few million years, via this process, Europa’s ocean can attain high concentrations of oxygen’s that are greater than those found on earth’s waters are. This oxygen can support not just anaerobic microbial life but also larger, aerobic life such as fish (Solway, 2013, p. 122). Geology Europa’s surface is generally varied and complex. It consists of various landforms such as chaotic terrains, the impact crater, linear fractures; simple troughs double ridges, intertwining ridges and linear fractures among others. Europa is among the top places in Jupiter in terms of becoming a habitat as well as the possibility of holding extraterrestrial life. Planetary scientist Galileo Galilei first discovered Europa in 1610. Progressively, a number of observations of Europa have been made over a number of years by using earth-bound telescopes and space probe flybys. Europa is majorly made of silicate rock that contains some iron core. Strips and cracks striate its surface, whereas craters are comparatively rare. The The cracks and streaks are believed to have originated from a number of volcanic eruptions that may have occurred over time. Telescope reveals that Europa is covered with a thin atmosphere that is primarily composed of Oxygen (Agus & Goldstein, 2011, p. 90-91). Geology of Ridges The unmanned landing mission will take a close look at the ridges as one of the major landforms found on Europa’s surface. Ridges are abundant on Europa’s surface. They are features cyclonic and straight in shape. Ridge consist of raised grounds such as hills and mountains found on the surface. Ridges are relatively random in orientation, usually with knobs at their intervals. Ridges found on Europa a surface were made through tectonic forces that generated a plate of ice sheets (National Research Council (U.S.), 2011, p. 22). Nature of anticipated evidence of life Europa’s subsurface is believed to be related to that the deep ocean hydrothermal surface while life has been detected. NASA reports indicate that Europa may contain both organic molecules as well as heat sources that often originate from the decayed radioactive elements and geophysical mechanisms. Unlike the Oxygen found on earth, Europa’s oxygen is not of biologic origin. The oxygen is formed by splitting of water into hydrogen and oxygen through sunlight. Europa is the smallest moons of Jupiter, yet it is relatively smaller compared to the earth’s moon. Data from Galileo depicts that Europa is made of a layered internal structure that includes a small metallic core. On the contrary, Europa surface is exceedingly smooth with three large craters located on its surface. Europa has a smooth surface that has led to the existence of Water Ocean that exists beneath its surface (National Research Council (U.S.), 2012, p. 77). Logistics Topography Europa’s topography As seen above, Europa has visible cracks that run from one end to the other, dark patches that contain both ice and dirt, visible icy water. Scientists from NASA indicate that Europa has images with signs of subsurface ocean water, craters, and a series of ridges on its surface among other landforms (Coustenis & Encrenaz, 2013, 89). Landing access Lander landing on Europa The installed landing sensors subsystems that consist of a dual redundant WFOV stereo imager and a laser rangefinder system will provide landing guidance. The attitude and articulation control systems (AACS) will be used in determining safe landing on Europa’s hazardous surface. Under the AACS, the landing guiding and control systems will provide an autonomous guidance and control for a safe landing that will require a six degree- of- freedom(DOF). The system will also support a thrust-vector control (TVC) as well as maneuver abilities to enable a precision soft landing. The spacecraft will use an autonomous trajectory and hazard free path, avoiding chaotic ice fields that may hinder safe landing. Requirements on the Europa lander guidance and control systems will entail two-body descent, movement dynamics and stability envelope estimates. It will also soft landing laterals, lander TVC algorithms for adjustable glide slope and maneuvering controls. The lander will have a terrain correlation tracking that will help in identifying in target landing site ( Greeley, 2013, p. 78). Instrumentation and nature of experiments Under this mission, the Europa orbiter will carry a laser altimeter, a radio subsystem suite of tools, a magnetometer, as well as Langmuir probe to help determine the electron temperature, the electric potential of plasma and the electron density. The proposals also calls for a Europa Clipper spacecraft that will carry the ice penetrating radar, a topographical image, an ion, shortwave infrared and neutral mass spectrometer that will help in studying the habitability elements of Europa. The instruments will also assist in identifying new sites for future Europa Lander missions (Agus & Goldstein, 2011, p. 53). Unlike with Mars, most missions to the outer are often expensive and rare. Identifying an appropriate rover design to get on Europa may not possible due its hazardous surface. Requirements A Europa lander mission concept entails landing a spacecraft on Europa with the ability to acquire some materials from the ridges, carryout detailed chemical analysis of the materials, and transit the results found directly on the earth. Due the large speed change required, four kilometers per second, the propulsion system will comprise of more than 85 of the 100 kg launch mass. This spacecraft lander will require a number of instruments such as lightweight, miniaturized organic chemistry tools, devices for acquiring, distributing, as well as processing surface, materials. The spacecraft modern systems will enable it to carry out an autonomous precision on Europa’s surface safely. The important measurements that will take place on Europa will include isotopic and elemental composition the existing ice, its melting point, redox potential, PH levels, conductivity and ionic and gas concentrations. The possible instruments appropriate for this taking the measurements include; the alpha proton spectrometer, tunable diode lasers, quadruples spectrometer and electronic tongue and nose (National Research Council (U.S.), 2012, p. 19). A drilling and coring tool will be required for retrieving ice cores. We also ensure that the electronic tongue contains a chamber that contains a vacuum seal to help create a liquid melt in the Europa’s high-vacuum environment. The possible imaging instruments will include optical microscopes, X-ray fluorescence devices, and scanning electron microscopes. The imaging camera will be mounted on a mast that will take pictures with a wider view covering a 360-degree field-of-view. A secondary lithium-polymer battery will be used in providing for energy storage during the mission. An advanced radioisotope source of power wills one of the major components of power subsystems. The attitude determination systems will comprise of fine sun sensors (Oachim Saur et al., p. 32-33). Bibliography Agus, M., & Goldstein, A. (2011). From the land of the moon. New York, N.Y., Europa Editions Belbruno, E. (2013). Fly me to the moon an insider's guide to the new science of space travel. Princeton, Princeton University Press. http://public.eblib.com/EBLPublic/PublicView.do?ptiID=1350176. Coustenis, A., & Encrenaz, T. (2013). Life beyond Earth: the search for habitable worlds in the Universe. Greeley, R. (2013). Introduction to planetary geomorphology. New York, Cambridge University Press Hayden, E., Henriksen, L., Payton, K., & Baumgartner, B. (2013). Astronaut: The Last Push. Massachusetts Institute of Technology. Graduate Program In Science Writing, Marcia Bartusiak, & Fitzpatrick, Garret R. (2013). Searching for life where the sun don't shine : explorations to the seafloors of Earth and Europa. Massachusetts Institute of Technology. http://hdl.handle.net/1721.1/76138. National Research Council (U.S.). (2011). Vision and voyages for planetary science in the decade 2013-2022. Washington, D.C., National Academies Press. National Research Council (U.S.). (2012). Assessment of planetary protection requirements for spacecraft missions to icy solar system bodies. Washington, D.C., National Academies Press. http://books.nap.edu/catalog.php?record_id=13401. Oachim Saur, Paul D. Feldman, Lorenz Roth, Francis Nimmo, Darrell F. Strobel, Kurt D. Retherford, Melissa A. Mcgrath, Nico Schilling, Jean-Claude Gérard, & Denis Grodent. (2011). Hubble Space Telescope/Advanced Camera for Surveys Observations of Europa's Atmospheric Ultraviolet Emission at Eastern Elongation. The Astrophysical Journal. 738. Solway, A. (2013). Jupiter and the outer planets. Chicago, Ill, Raintree. Read More