Lab7 Google Mars Activity 18 PDF

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GeoSci 120: Geology of the Planets Spring 2018 Dr. Lindsay McHenry LAB DUE: FRI, MAR 16, 11 PM

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LAB 7: GOOGLE MARS! You may be familiar with Google Earth, a convenient program for accessing highresolution satellite imagery of Earth surface features (including your own house). With Google Earth 5 (and more recent versions), this coverage was extended to the Moon and Mars! The global base map is based on Viking and Mars Global Surveyor (MGS) data. The higher resolution colored areas come from the European Space Agency’s Mars Express, and the very high resolution grayscale map portions come from HiRISE images from the Mars Reconnaissance Orbiter (MRO). You can also select “colorized terrain” (check the box under “Global Maps”), which gives you broad-scale topographic information (from MGS). This might be the best view to use to make out the major features on the planet’s surface. You can also select “CTX Mosaic” which will give you fairly high-resolution images from MRO’s CTX camera where available. Step 1: open Google Earth. You’ll need the actual program installed on your computer (Google Earth Pro), rather than the web version, to do this lab. If you don’t already have it, here’s the link to get it: https://www.google.com/earth/desktop/ Step 2: If you haven’t used Google Earth before you’ll want to practice a bit- move around the planet dragging the mouse, change the magnification by right clicking, using the magnification slider on the upper right, or your mouse’s scroll wheel. You can “Fly to” (or search for) any named feature on the map so if you know the name of some feature (e.g. a specific volcano, country, a city, or even your home!) you can go there directly. On the lower left are layers that can toggle on and off which include countries’ borderlines, photos users have taken, roads, and more. On top are various tools, such as a ruler for measuring distances. Play around for a bit and get used to the program! Step 3: When ready, click on the little planet icon in the top bar, select Mars. You are now looking at an interactive Martian globe! Step 4: Orient yourself- can you find major features, like polar ice caps, Olympus Mons, Valles Marineris, and Hellas Basin without searching for them by name? Hint: this might be easier if you switch to “colorized terrain” in the Layer manager in the lower left. Just make sure you switch back to “visible imagery” or “CTX Mosaic” if you zoom in to small features- the elevation map is not nearly as detailed as the visible imagery. The red, orange, and blue squares are markers or links to additional data from other instruments. Red squares are HiRISE images from MRO. Zoom in to one of the grayscale HiRISE images to see a close-up of the Martian surface (width of each image: 6km).

Orange squares represent CTX images (width of each image: 27km). You can really see the contrast in resolution between the global images and the HiRISE when you look at the boundary between them. If you don’t see the orange and red squares, go to “layers” on the left, expand “spacecraft imagery,” and make sure that the HiRise Image Browser and CTX Image Browsers are checked. Some HiRISE and CTX images come already map-projected and loaded onto Google Mars- for HiRISE you’ll see them as grey strips on the Colorized Terrain map, for CTX you can switch to the CTX Mosaic base map to see many of them. Note: if you have a slow Internet connection these higher resolution images can be slow to load. Most HiRISE images are NOT presented this way and you’ll have to go access the image yourself. You can access the high-resolution HiRISE and CTX images by clicking on the little square (red for HiRISE, orange for CTX), right clicking on the link near the center of the dialog box to give you the option to copy it, and pasting it into a web browser. Sometimes there is a convenient writeup on the image that can help you answer your questions. Once you access the record you can click on the appropriate link to view the high quality image. Let’s get started! By copying and pasting the latitude and longitude into the “Fly to” (or Search) field you can zoom in to these specific spots. 1. P22_009826_1865_XN_06N348W, CTX (orange square) image located at 6.353°N 11.85°E [Load the image from ASU’s data page. Click on the image panel on the left for the fullscreen view]. Note- you’ll need to zoom out to really tell. a. What kind of feature does this image cross? Use the Base Layer view on the website to help you answer this question. Olympus Mons. The feature allows me to pinpoint the location of Olympus Mons on Mars. b. Do you think this feature is old or young? Cite two pieces of evidence for your assessment. I didn’t know this technology was available. So, of course, I believe this feature is young! We’re able to pinpoint various locations on Mars. For somebody that isn’t the best at science, I am very, very intrigued. I believe this feature is young because I am still blown away by Google Earth. Oh, by the way, if we’re talking about the crater and not the software… well, yeah, I think it’s new. You can tell there’s a crater within the crater on the side. And the land looks clean. 2. Next, fly to (search for) 17.28°N 226.67°E. This shows a similar feature to that in the previous question, but at the opposite end of the “age” spectrum.

a. Is this feature old or young? Cite two pieces of evidence for your assessment. If we’re talking about the crater – it’s full of some smaller craters, so it’s probably new. Pangboche

b. How big is the feature, in both depth (or height) and width? To get width, click on the “ruler” icon and then click on two points on the map. Make sure your units are in meters or kilometers! To get depth or height, compare the elevation of a point at the bottom and at the top of the feature. You can read the elevation at the bottom of the screen- it will read the elevation of the spot where your mouse is. The width of the feature is roughly over 9,400 meters. While the depth is roughly 1,500 meters. “Tectonic” features on Earth and Mars Example of a rift valley (extension) on Earth Before we fly to our next Mars image, let’s look at a similar feature on Earth. Note that this feature on Earth will look rather different than the feature on Mars because of the vegetation and water, which don’t exist on Mars, but let’s take a quick look anyway. Click on the Saturn symbol and select Earth. So that the map is not cluttered, under Layers, un-check the green box next to Primary Database. Under the Gallery layer, check Gigapxl Photos ONLY. Now, in the ‘Fly to” type New Mexico. In the top of the map there should be a picture icon called “Rio Grande Gorge Bridge”, double click near the icon (not on it) to zoom in. As you zoom, you should see the rift. Click on the photo icon, then in the pop-up window click on the “Fly into this ultra high-resolution photo”. There is an Exit Photo button in the top-right of the map. Return to Mars. 3. Cerberus Fossae Fracture PSP_004006_1900, HiRISE image located at 10.05°N 157.61°E This image shows a tectonic feature. What kind of movement – extension (divergence, or “rifting”- two sides moving apart from each other), compression (convergence- two sides coming together), or lateral motion (transform- two sides sliding against each other laterally) – do you think formed this feature? Explain your answer. Most likely formed by faults that pulled the crush apart in the Cerberus region. The cause for the faulting was mostly likely pressure from magna related to volcanic are of the planet which probably makes it young.

4. Now ‘fly to’ (search for) Athabasca Valles, a long linear depression that stretches NESW across the surface. Examine the global imagery (including visible, colorized

topography, day and nighttime thermal infrared, and CTX Mosaic) and zoom in and out to get a good sense for the feature. It might be easier to see if you un-check the HiRise and CTX Image Browsers to get rid of the red and orange boxes. a. Grab a map image of Athabasca Valles using the map layer under Global Maps that contributes the most detail. To save a map image, go to File>Save>Save Image, and the program will use the current view to make a map image. Provide a map name, make sure the scale is how you want it (change the scale by zooming in and out of the feature), and the North arrow is up. When done, hit the Save Image button at the top, and import it into your work. b. What is the size of Athabasca Valles? Include length, width and depth values. To get length, click on the “ruler” icon and then click on two points on the map. Make sure your units are in meters or kilometers! To get depth, compare the elevation of a point at the bottom and at the top of the feature.

The Athabasca Valles is roughly 285 kilometers in length while width is roughly 250 kilometers and the depth is 70 kilometers

c. Next, based on its overall shape and size of Athabasca Valles and the features visible in the CTX and HiRISE images (you might need to go check the HiRise and CTX image browsers again, if you unchecked them when you made the map), how do you think Athabasca Valles formed? Be specific in your answer, listing as many landforms as you can to support your interpretation. Note- if you look at the larger orange or red boxes, you might be able to use part of the writeup associated with the image, courtesy of ASU or the University of Arizona.

They were formed as steamed exploded from the lava flow.

d. What was the flow direction in Athabasca Valles? Southwest Exploring a landing site 5. Fly to Gale Crater. You will see that there is a LARGE concentration of HiRISE images taken in this area in support of Mars Science Lab Curiosity, which landed there in

2012. Find a HiRISE image that shows the tracks of the Curiosity rover (look for one from 2014 or so). a. Copy and paste the image (a screen shot is fine) into Word or PowerPoint and then crop the image until the tracks are clearly visible. Label your slide or document.

b. Then click on one of the “camera” symbols for a panoramic picture taken from the rover itself! If you don’t see available panoramas, you can view a list of them under Mars Gallery/ Rovers and Landers/ MSL Curiosity/ Gale crater landing site/ Rover sites. Another possibility would be to look through the panoramas made by Curiosity. Make sure you pick one that includes tracks or SOMETHING man (or rover) made in your field of view. Select the option to “fly in” to the high-resolution photo, then copy and paste your image onto the next slide of your PowerPoint, and label your slide. If you have trouble using the “fly in” option in Google Mars, you can always follow the link to the Mars Curiosity Rover Panorama Gallery and view these images there, online.

c. Zoom out a bit, and click on one of the larger red squares (these are often HiRISE images with titles and explanations). Find one that shows the layered deposits (on the slopes of Aeolis Mons), and copy it into your PowerPoint presentation (next slide) or Word (next page) document.

d. How many layers can you see in succession? Not sure there are an apparent periodic number of layers e. Which layers do you think are oldest? Not sure there isn't a self-evident obvious number of layers... if that makes sense f. What is a reasonable explanation for how the layers could have formed? One word: Erosion

6. Why did they pick Gusev Crater as a landing site for MER Spirit? Scientists were disappointed with the preliminary results from Gusev Crater, when they discovered that it was mostly a field of lava rocks. That’s not what they had expected when they selected the site.

Navigate to Gusev Crater. You’ll have to zoom way out to actually see anything. You will see a big cluster of HiRISE images of the central part of the crater, where Spirit landed. Ignore these and look at the southern rim of the crater (and south of the crater). a. Can you see the features that might have led the MER team to select this as a landing site in anticipation of finding evidence for water? Briefly describe. Yes, they look like river basins so naturally you would think that water would be flowing or underneath the ground. b. Make a map image of the feature implying evidence for water. Use the map layer that defines the feature best. Include a scale bar.

7. Now it’s time to explore! Pick two of the following destinations that you find particularly interesting, go explore it, look at the HiRISE image writeup, then provide a summary of what you saw! 23.02°N 243.32°E flood carved rock 5.09°S 137.23°E Chasm in Gale Crater’s interior mound 34.23°N 141.58°E Streamlined islands in an outflow channel 23.82°S 326.48°E Eberswalde delta

84.53°N 343.38°E Polar layered deposits 70.23°N 103.54°E Ice pond crater! Summary of feature 1: 23.02°N 243.32°E flood carved rock I see a river basin with occasional large bodies or pools that would be filled with water.

Summary of feature 2: 84.53°N 343.38°E Polar layered deposits I see either the same as feature 1, but larger or sand that created a huge dune. Or maybe it’s a crater.

Make sure you save your PowerPoint presentation or Word document (title should start with your last name) and upload it to the Dropbox, along with scans or pictures of any sketches!...