St. John Bosco Mars Project Essay The question chosen for this project was, what is the relationship between crater

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1 St. John Bosco Mars Project Essay 2012 The question chosen for this project was, what is the relationship between crater diameter and wind streak length. Two hypotheses were formulated to answer this question. The first hypothesis was: the larger the diameter of the crater, the longer the length of the wind streak. This hypothesis was believed to be true because a larger crater diameter provides a larger area for dust to be picked up and scattered behind the crater causing a large wind streak. The second hypothesis was: the smaller the crater diameter, the larger the length of the wind streak. This hypothesis was believed to be true because a smaller crater provides less area for the dust to be blown into the crater and more area for the dust to lay behind the crater forming a longer wind streak. The importance of this question was to understand the landscape of Mars. It can be compared to the landscape of Earth, which is more familiar to the students conducting the study. The background behind the project consists of definitions, scientists, and patterns. Some definitions that were needed to know are: Wind streak: a streak of dust trailing craters; there are three different types of wind streaks, light, dark, and splotch-related dark. Shadow zone: an area of a wind streak where deposition preferential occurs. Usually dark streaks are broader and shorter than light streaks. Also some scientists that help provide us with prior knowledge were: Thomas, Veverka, Sagan, and Greeley. They created a hypothesis on the three main types of wind streaks. Also Greeley attempted to model Mars wind streaks in wind tunnels and discovered the shadow zone. Thomas and Veverka found patterns in Tharsis volcanoes, Syrtis Major, and Elysium. The global wind streak patterns are controlled by the global dust storms that occur yearly. The center of the dust storms shift from hemisphere to hemisphere. The dust storms lead to an increase in wind which then leads to an increase in wind streaks. These patterns are a clear reflection of global circulation patterns. The patterns of the streaks do change.

2 Light wind streaks are formed by the uplifting of dust that spreads and drops around a crater as the wind slows down. Dark wind streaks are formed by the erosion of basalt, a dark colored rock that makes up the majority of the surface of Mars. The craters can be formed in two ways. When a volcano collapses it creates a crater called a caldera. The more common type of crater is the impact crater that forms when a meteor, comet, or any space object hits the surface of Mars. Within the experimental study to prove the wind streak hypothesis there were many tools used. The tool the students used most frequently was JMARS, which included THEMIS stamps, Shape layers, THEMIS Night Over Day, MOLA Shaded Relief (NE), and Lat/Lon Grid. JMARS is the application used to study the surface area of Mars. It consists of many photographs taken from the satellite orbiting Mars, called THEMIS. This application gives scientists different computerized tools to measure the craters and wind streaks. Certain regions of the red planet can be studied with different THEMIS stamps and layers added. THEMIS Stamps is a tool where scientists are looking at a specific place and when the layer is added, there are boxes that appear in the area. It isn t everywhere in the area, areas where there is a lot of activity is boxed. Shape Layers are a specific area set up by a coordinator or an instructor. This is a file that when loaded, a specific area on the map is boxed. This is what is instructed to study the area. THEMIS Night Over Day shows the temperature difference between night and day. This is helpful when studying an area because the area could have possibly been affected by temperature. MOLA Shade Relief (NE) shows the different heights of surface features on mars. This is helpful when scientists are studying an area of Mars (i.e. craters, volcanoes, wind streaks, etc.) The latitude/longitude grid is a tool used to measure an area of Mars. This is used to measure the length of wind streaks and to measure the diameters of craters, and more. The controls used at Mars were latitude and longitude around Syrtis Major. The ranges were 0-20N and E. These were used because these were the ranges around the Syrtis

3 Major range. The resolution of the camera was also a control. This was used because we could only use the THEMIS images. For the project the students were separated into groups. They all decided what they would like to study and came up with a question and hypothesis. They wrote their proposals and sent one with the most provable hypothesis in. When the students were preparing for the Mars Project, they began to target the images with the features that they would study according to their hypothesis, and then they tried to find and identify as many wind streaks as possible. When the students arrived at ASU, they opened JMARS. Then they analyzed the wind streaks, graphed, and concluded. Thirty-three images were collected from the JMARS application. More than thirty-three craters were observed because there was more than one crater in most images. From the THEMIS images that were observed, craters and wind streaks were able to be identified. The craters diameter and the wind streaks length were also identified.

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7 The diameter versus length graph proved that there is no distinct relationship between wind streaks size and the crater diameter. The dark wind streaks tended to be shorter in length while the lighter wind streaks tended to be longer in length. The latitude and longitude plot map proved that dark wind streaks tended to be found in dark clumps while lighter wind streaks tended to be found in light clumps and were more scattered than dark wind streaks. The light wind streaks were more common throughout the area that was studied. This can help infer that wind streaks on Mars are in multiple directions, and also that Mars produces a large amount of craters. This could be related to the wind speed on Mars. During the experimental study, the students found inaccuracies in the data. Outliers, or points that lie separated from the other points on a graph, greatly influence the outcome. Also, some of the crater identification numbers were not recorded. There was some bias in the data as well. Confidence levels varied and wind streaks were measured differently according to human interpretation. In addition, only specific craters in Syrtis Major were measured and recorded. Finally, the infrared layer was accidentally placed on images and it gave the wind streaks a different appearance. The students conducting the experimental study did not prove their hypothesis that the larger the crater diameter, the longer the wind streak. We proved there is little to no relationship between the crater diameter and the length of wind streaks because of the R of 0.6 in the scatter plot which cannot make data conclusive. For future references we would like to look at different parts of Mars, measure different wind speeds on light and and dark wind streaks, find the amount of dust, and test more craters. Furthermore, we would like to find craters with definite wind streaks that change over time.

8 We would like to thank the MSIP program for allowing us to take part in MARS research. Also, we would like to thank Ms. Whalen for organizing the event year in and out. Lastly, we would like to thank Mr. Leon Manfredi for taking the time to teach us the interesting aspects of Mars.

9 References: Mars Student Imaging Project Resource Manual (Keith Watt, Sarah Watt) On Mars (Patrick Moore) The Surface of Mars (Michael H. Carr) Websites: themis.asu.edu People: Leon Manfredi: MSIP Instructor Meg Hufford: Mars Mom