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Diorama Scavenger Hunt Cards # What’s shown in the picture 2 Close up of dust collecting magnetic ring 3 4 5 9 Label on Picture Find this device that resembles a row of three targets. These circles are magnets for collecting high-iron magnetic dust grain from the air. Close-up of Note the dust tail behind scattered rocks the two largest halfand dust tail buried rocks. Which way does the wind blow to create these dust tails? Close-up of This big dark rock has medium sized been chipped. Does the rocks chip look natural or human made? Close-up of a This device receives wire dish data from the orbiting antenna Mars transport spacecraft, which serves as an orbiting Mars station. Close-up Wind The very thin speed indicator atmosphere on Mars makes an ordinary anemometer (wind speed indicator) useless. Can you locate this digital anemometer? Enrichment Facts MGGs can share with visitors The magnets collect dust out of the atmosphere. By analyzing the chemical composition of these dust grains, we can determine where on Mars the dust originated. This tells us about wind patterns on Mars. Notice the variety of rocks seen together. Apparently the wind blew away all the lighter material leaving solids behind. Some the pink light colored rocks are sedimentary. The dark rocks are igneous. Most likely it was chipped by the astronaut activity. This low-gain antenna sends and receives radio signals from the spacecraft in Mars orbit. The spacecraft then communicates with stations on Earth. The time delay for radio signals between Mars and Earth ranges from 4 minutes to 20 minutes depending upon where Mars and Earth are in their orbits. Since the atmosphere on Mars is too thin to spin a cup anemometer, a digital anemometer is used. The wire is heated like the filament in an incandescent bulb. As the wind flows over the wire, the wire is cooled. The rate of cooling will indicate the wind speed. Three wires aligned along orthogonal (mutually perpendicular) axes provide data that can be reconstructed to give speed and direction of wind. 12 Close-up of large igneous type rock 7 Phobos & Deimos When the pictures of Mars came back from the Pathfinder mission in 1997, scientists gave each prominent rock in the pictures a nick name like Yogi and Little Joe. Can you think of a name for this rock? Look for these two bright objects in the Martian sky. They’re moons but not like the Earth’s big shiny moon. This igneous rock is obviously different from the sedimentary rocks which predominate in the canyon. How the igneous rock arrived here can tell a story about Mars. The rock could have arrived in its location by being ejected after a meteorite impact a long distance away from here; or it could have been thrown out by volcanic eruption or it might have fallen from a cliff at the time when this canyon was much narrower than today. Martian Moons: Phobos, Mars’ larger moon, the larger dot in the sky, and Deimos (smaller dot) are visible in the northwest sky. Phobos (“fear”) and Deimios (“terror” so named because they accompany the Roman god Mars, god of war). (For an animation of these see Starry night Pro.) Data for Mars Moons moon 13 Layered “Hoo- Find this stack of rock, a doo” with hoodoo, which is a tall background thin spire of rock that protrudes from the bottom of an arid basin. It probably formed due to wind erosion by strong prevailing winds. Phobos Dimensions (miles) 12x14x17 Distance from Mars (miles) 5,760 = 1.3 Mars diameters Orbital period 7.7 hours Deimos 6x8x10 14,560 = 3.5 Mars diameters 30.3 hours Comment Moves horizon to horizon in under 3.85 hours. Since this is faster than Mars’ rotation period, it appears to go west to east, “backwards.” Horizon to horizon in 15 hours (Appears to move east to west, “forward” as Earth’s moon does.) The material in the hoodoo is a type of sandstone. The hoodoo itself suggests wind erosion. Earth examples of hoodoos can be found in Bryce Canyon, Utah and the Badlands of South Dakota. 14 15 LAN Communication antenna Layered rock strata plus medium background 16 Base of support pole for table This device is part of local a Local Area Navigation (LAN) network, similar to GPS, but ground based. This canyon eroded when a crack on the Mars surface widened laterally due to permafrost erosion, leaving behind some distinctive land forms. Find the thimble shaped outcrop in the center and the mesa nicknamed “short stack” because it looks like pancakes. These features can be seen from above on the photograph behind you on the right. Can you find this location? Has the weight of the table leg gouged into the rock, or is the rock hard enough to support the load? 18 Gravelly exit How many different kinds of rock can from arroyo on you see here? stage right 19 Support structure between PAM and Cargo Bay door Astronauts are construction workers: they set up pre-fabricated structures once they arrive on Mars. Can you find the strut in this structure? The LAN network connects the various buildings, instruments and astronauts using Line-Of-Sight communications. It triangulates from three or more signals, much like the LORAN radar that is still used in some harbors on Earth. Candor Chasma most closely resembles a rift valley, a fault line that opens up by widening, on Earth. The initial fissure was likely caused by the weight of the Tharsis lava flows or perhaps due to a planet-shaking tectonic event associated with the large impactor that formed Hellas Planetia. Once the ground fractured, newly-exposed permafrost then sublimed (evaporated) away. The loose rock and soil on top of the permafrost layer, slid into the canyon, where the wind excavated away the light material leaving behind the harder rock we see here. The end result is the solar system’s largest canyon—at least as far as we know. To turn loose sand or ash into rock requires that the material is buried and compressed. We know that in the past, Mars’ surface did subside (sink) then later re-emerged. This must have been due to the underground flow of magma (lava that never reaches the surface). Apparently all such movement has ceased due to the cooling of the Martian interior. These rocks probably got here by simply being left behind as the wind blew away the soft material in which they were embedded. A second possibility is that running water that existed on Mars long ago dumped them here. Chandor Chasma canyon, though is NOT a water-carved feature as the Grand Canyon on Earth is. One of our astronaut crew’s missions is to construct a brick factory. The crew are exploring ways to be more self-sufficient on Mars. NASA’s astronauts are currently working as construction workers on the ISS 20 Cracks in layered rocks Martian landscapes do change over time, but slowly. Can you locate these fractures in the rock that might be due to an ancient Marsquake? 21 Layers of rock plus a fallen boulder 22 Eye ring in rock layer Shadows on Mars are very dark and cold due to the lack of dispersed solar energy in the thin Martian air. What happens to very cold material, even solid rock, that is suddenly thrust into direct sunlight as the morning sun rises? Can you find this point of attachment of the guy wire? These rocks layers are hard enough to support the eye bolt. 23 Cable hardware on PAM Much hardware on Mars is off the shelf stuff from earth, carefully selected and tested. Can you find this hardware? 25 Vertical face with face 26 Boulder cobbles, wind fan, rock layers Can you see face in this rock outcrop? Are such faces on Mars or in the eye of the beholder? Also note the color of the sky, a combination of light scattered from dust particles and the low angle of the sun passing through the hazy air. This boulder fell from the layer above it. Can you find the location it fell from? Two sesimometers were flown on the Viking spacecraft back in 1976. One of them worked, the other failed. Because the seismometers were located within the spacecraft body and were not isolated, they mostly recorded rocking due to the wind blowing over the lander body. There was one event that was recorded during the night (when the winds were low) that might be a Marsquake. We can conclude that if quakes still happen on Mars, they are very rare and very slight. Expansion and contraction caused by extreme temperature swings (from minus 200° F to positive 70° F) can cause the rocks to crack, especially when the sun light hits them, after a long cold Martian winter night. To turn loose sand or ash into rock requires that the material is buried and compressed. We know that in the past, Mars’ surface did subside (sink) then later re-emerged. This must have been due to the flow of magma (lava that never reaches the surface) deep underground. Apparently all such movement has ceased due to the cooling of the Martian interior. While some specialized components will need to be created for planetary missions other components will be “off-the-shelf.” However, even common looking items will need to be specially engineered in order to handle the harsh conditions on Mars: the extreme temperature variation, high levels of ultraviolet-C radiation, and exposure to charged particles in the solar wind and galactic cosmic radiation (cosmic rays) which reach Mars’ surface due to its lack of magnetic field. The high noon color of the Martian sky is pink, and stars can be seen in the thin air. At sunset the sky around the sun looks bluish. Rockslides caused by permafrost sublimation (evaporation) are a main cause of erosion. Mars’ surface is still be shaped by wind erosion and gravity. Candor Chasm is still growing wider, though we don’t know at what rate, an inch a year or a landslide every decade.