ANALYSIS OF CURIOSITY S PATH UP MOUNT SHARP, GALE CRATER, MARS

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1 ANALYSIS OF CURIOSITY S PATH UP MOUNT SHARP, GALE CRATER, MARS Brayden M. Van Ackeren Department of Economics University of Hawai i at Mānoa Honolulu, HI ABSTRACT NASA s Curiosity Rover has been the focus of operations on Mars for over a year, and the details of the missions are not officially set. NASA would like to send the rover up Gale Crater s Mount Sharp, and the mission team set a planned entry point just over five kilometers from its current position. There are a multitude of options up the mountain from this entry point, some more beneficial than others. From the planned entry point I have proposed a pathway that would lead the rover to multiple scientifically significant sampling and data collection zones. I also created a secondary pathway that is meant to be an option if the primary pathway proves to be too hazardous to traverse. Both pathways start from NASA s planned entry point and finish at the same location on Mount Sharp. INTRODUCTION With the help of my mentor, I was able to analyze a potential pathway for NASA s Curiosity Rover. Figure 1 illustrates where the rover was on Sol 343, and the planned entry point for climbing Mount Sharp, the primary objective for the mission. This pathway occurs after the NASA s already planned maneuvers and should be a candidate for consideration when determining the potential actions of the rover. Figure 1: View on sol 343, looking S.E. across Gale crater from the Curiosity rover. Using satellite images and topographic data from NASA s Mars Reconnaissance Orbiter and ESA s Mars Express, I was able to identify potential hazards as well as points of interest. Being that Curiosity is a part of NASA s Mars Exploration Program and is tasked with the determining if Mars can support microbes, it should be exploring different geologic settings. 88

2 Along the proposed pathway the rover would encounter a multitude of different geologic units, settings, and surroundings, all which could provide much insight into the geologic history of Mount Sharp, Gale Crater and Mars. METHODS In order to create a pathway that would best serve the mission as a whole we must focus on a few priorities. First, being that the primary objectives of the mission is to make various geologic measurements and so the rover must travel to a diverse variety of locations. Second, the rover must attempt to avoid as many hazards as possible, in order to ensure future use of the rover and the continuation of the mission. These are the two main priorities of the mission the rover must meet these requirements before making any movements up Mount Sharp. In order to make this pathway it was necessary to use multiple data sets in order to ensure accurate measurements and visuals. For this task, I focused on four main types of data, High Resolution Stereo Camera (HRSC) digital elevation models, High Resolution Imaging Science Experiment (HiRISE) images and digital elevation models, Context Camera (CTX) images, and Compact Reconnaissance Imaging Spectrometers for Mars (CRISM) mineralogy identification. The digital elevations models were used in order to determine the changes in elevation over distances. CTX and HiRISE Images were used to identify any potential hazards that would be easily viewable from the satellite images and well as changes in geologic units. Finally the mineral identification data were used in order to identify areas that are considered to have significant mineralogy. From these data sets (Figure 2), I created a geomorphic map of the study area to distinguish the best pathway based on the two main priorities discussed earlier. Figure 2: Diversity of data sets used in this investigation. Left, HiRISE image of study area. Center, the geomorphic map that I created to identified different units in the image. Right top, CRISM image on top of HiRISE digital elevation model. Right bottom, my geomorphic map on top of HiRISE DEM. 89

3 Before identifying a path, I also had to be sure that I could correctly identify the landforms from the perspective of the rover. Figure 3 illustrates the 11 different hills that can be seen both from the orbiter and the rover. Figure 3 (Left): (Top) Numbered landforms identified in HiRISE image of N.W. Mt. Sharp. (Bottom) The same landforms as viewed from the Curiosity rover on sol RESULTS NASA s entry point is the start of my proposed pathway, referred to as Location A (Figure 4). From there the rover will begin its travel up the base to mount sharp to Location B. From that point the rover could either travel directly to Location F and the on to the final location, Location G. Or the rover could travel along scientifically superior pathway passing through Locations C, D and E before reaching point F. Both have their advantages and disadvantages, but pathways end at the same location at a point of interest at location G. All of these locations are listed in Table 1. Location Latitude Longitude A 4 o S 137 o E B 4 o S 137 o E C 4 o S 137 o E D 4 o S 137 o E E 4 o S 137 o E F 4 o S 137 o E G 4 o S 137 o E Table 1: Identifies Latitude and Longitude of the locations of major points along the proposed pathway. The path that goes to every location on my proposed pathway has areas that would be very interesting for data and sample collection. Location D is the first significant spot due to its delta like characteristics. This area could give insight to a possible flow through the location as well as geologic history of the area. Location E is the other important site along the pathway because of its proximity to a multitude of small mounds, sand dunes, mineralogy and geologic diversity. The area could give insight to the origin and modification of Mt. Sharp. 90

4 Not only do the settings themselves provide great sampling opportunities, but the pathway between the two spots allows for great data and sample collection opportunities. The secondary option does not stretch across as many high quality data collection sites, but it has its own set of advantages. By going straight from Location B to Location F, we avoid a number of treacherous areas. By avoiding these areas we assure the safety of the rover, while still continuing along the path. We may be able to collect data at locations that may be similar to what would be found on the primary pathway, but there would be no guarantee of this. If one preferred a safer path to one that collected more significant data, the secondary option would prove to be the pathway of choice. Figure 4 (Left): The identified pathway is illustrated by the white lines. The solid white line displays the primary pathway, which is ~13.5 km long and covers an elevation change of ~1,080 m. If Curiosity drives at 20 m/sol, it would take ~327 sols to get from Point A to D, and 675 sols to go from Point A to G. The average slope that the rover must climb would be ~4.6 o. The primary option proves to be longer and more hazardous, but reaches more geologically unique destinations. The secondary option differs from the primary option; the altered pathway is shown by the dotted white line. DISCUSSION We would expect to see many things that we would see in other parts of the planet along this pathway. We will often see more of the same as we start our climb up mount sharp, large spans of rubble and rock. What makes this seemingly common stretch of land interesting is the potential process that led to its current position. The material at the bottom of the mountain could have been placed there as a result of the modification of Mt. Sharp, loose debris being pulled down the mountain to its base. It also could be placed their as a result of the original impact that caused the crater to form. Either way me must collect samples the landscape at the base of the mountain in order to compare it to the materials found at the top of the mountain. 91

5 The reason this pathway was chosen is because it produces the largest variety of data and sample collection opportunities. Sand dunes (Figure 5) prove to be a hazard to the rover as well as an opportunity to learn more about the geology and mineralogy of the planet. There are a multitude of sand dunes along the path up Mt. Sharp. While we should be able to go along the pathway without driving through any of the sand dunes, the areas surrounding the sand dunes are sure to multitudes of sedimentary features to analyze. Large sedimentary mounds could be photographed, while smaller rocks, and loose sand can be collected and analyzed. The sand dunes while hazardous could lead to multiple findings regarding the mineralogy and geologic history of Gale Crater and Mount Sharp. Figure 5 (left): Sand Dunes located at point G on the pathway. As we start to increase in elevation, the rover would start to approach cliffs and other steep inclines areas. As does the Grand Canyon or other cliffs, the abundance of exposed, vertical, spans of Mount Sharp can give insight into the modification of the mountain. From satellite images we can see layering, but until Curiosity gets to these sites and collects photos, samples, and more, we are unable to determine a highly accurate number of layers. As with all steep changes in elevation, the cliffs will hint to the modification of the Mountain, answering what process led to the formation. One of the most interesting things that can be seen from HiRISE satellite images is the orientation of the layers on Mt. Sharp. Using HiRISE images linked to a DEM we are able to see that layering with different orientations (Figure 6). In some areas, the layers area parallel to the contour lines, meaning that the layers lay flat on top of each other. In other areas the layers are found to cross the contour lines meaning that they are tilted. The differing layer orientations give insight into the origins and modifications of Mt. Sharp. Layer size also varies, in some locations the layers are over 10m thick and in others we see much thinner layers. With the debate over the processes that formed this unique mountain, we must gather more data at locations like this in order to determine what occurred in this location. 92

6 Figure 6 (left): Layering in the left image on the left runs parallel to the 10 m contour lines. While layering displayed in the right image crosses over the contour lines. If the rover, while traveling along either pathway, was able to maintain a speed of 20 m per a Sol and made no stops, barring complications, the rover would reach location D in 327 Sols, and location G in about 675 sols. The average slope during this climb would be ~4.6 o. Because we propose that rover should make stops along the pathway, we believe this from start to finish it would take one Martian year (687 sols) at a minimum in order to traverse to the selected locations. The journey would cover 13.5 km of diverse landscape and geologic features. CONCLUSION Curiosity s mission on Mars is to explore the Mt. Sharp and Gale Crater and to determine if microbes could in fact live on the planet. It would therefore be in the best interest of the mission in order to explore a variety of different locations. These locations should vary in their characteristics allowing the rover to be collecting a large quantity of data. This Space Grant Fellowship has enabled me to explore some of the geology that Curiosity could explore, and to study the topographic features that would be encountered. Earth has proven that different species can live in a multitude of different conditions given a few basic necessities, which means that the Curiosity Rover must explore different locations. My proposed pathway allows for this to occur, and does it in a way that is also beneficial to other scientists who worked on the mission. Along the pathway the rover will be able to test its maneuverability, as well as collect air and ground samples at different elevations. The pathway is about maximizing the potential of the mission, so that the people of this planet can further expand their knowledge. ACKNOWLEDGEMENTS I would like to thank the Hawai i Space Grant Consortium at the University of Hawai i at Mānoa for giving me an opportunity to explore scientific research. This opportunity granted me the ability further explore and expand my interest in space and non-earth planetary. Also the research skills that I gained while in the project helped to better me as a student and a person. I was able to develop my problem solving and time management skills as a result of the project that will help me in every part of my future. I would also like to thank Dr. Peter Mouginis-Mark. As my mentor, he was able to teach about Martian geology and guide me through the struggles of research. 93