Thursday, February 27, 2014

Small Pale Red Planet Issue 3 Phase 8.1

 

The Aeolis Region

MC-23

 

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Topographical Map of the Aeolis Region

The Aeolis quadrangle covers 180° to 225° W and 0° to 30° south on Mars. It is famous as the site of two spacecraft landings: the Spirit Rover landing site ( 14.5°S 175.4°E) in Gusev crater (January 4, 2004), and the Curiosity Rover in Gale Crater ( 4.5°S 137.4°E) (August 6, 2012).

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Two Rovers in the Same Region\

 

A large, ancient river valley, called Ma'adim Vallis, enters at the south rim of Gusev Crater, so Gusev Crater was believed to be an ancient lake bed. However, it seems that a volcanic flow covered up the lakebed sediments. Apollinaris Patera, a large volcano, lies directly north of Gusev Crater. Gale Crater, in the northwestern part of the Aeolis Region, is of special interest to geologists because it contains a 2–4 km (1.2–2.5 mile) high mound of layered sedimentary rocks, named "Mount Sharp" by NASA in honor of Robert P. Sharp (1911–2004), a planetary scientist of early Mars missions. More recently, on 16 May 2012, "Mount Sharp" was officially named Aeolis Mons by the USGS and IAU.  Some regions in the Aeolis Region show inverted relief. In these locations, a stream bed may be a raised feature, instead of a valley. The inverted former stream channels may be caused by the deposition of large rocks or due to cementation. In either case erosion would erode the surrounding land but leave the old channel as a raised ridge because the ridge will be more resistant to erosion.  Yardangs are another feature found in this Region. They are generally visible as a series of parallel linear ridges, caused by the direction of the prevailing wind.

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Image of the Aeolis Region

Image of the Aeolis Quadrangle (MC-23). The northern part contains the Elysium Planitia. The northeastern part includes Apollinaris Patera. The southern part mostly contains heavily cratered highlands of Terra Cimmeria.

 

The first feature we come to in this Region is the Aeolis Mensa.  It starts from the northeast corner and proceeds to the southeast it is a huge broken up Mesa from 135-145°E going as far south as 7°.

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This image shows a central peak that is surrounded by a ring-like graben feature and relatively flat terrain. Does the graben show evidence of what geologists call "differential compaction"?

Compaction refers to sediment that is originally porous and is covered up by other sediment (called "loading") that reduces that porousness. In other words, sand particles are pushed closer and closer together. Differential compaction is when there is variation in the thickness of a given area that creates uneven surface and has different degrees of porosity. The presence of the graben might be a clue to the formation of such unevenness.

 

To the east of this feature from 145-150°E is the Aeolis Planum.  A long plateau going to the southeast surrounded by valleys also stretching  as far south as 7°.

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Aeolian Erosion Near Aeolis Planum

The wind is responsible for the erosion seen in this VIS image near Aeolis Planum.

Aeolis Planum

The Landing of the Curiosity Rover:

 

Curiosity was launched from Cape Canaveral on November 26, 2011, at 10:02 EST aboard the MSL spacecraft and successfully landed on Aeolis Palus in Gale Crater on Mars on August 6, 2012, 05:17 UTC. The Bradbury Landing sit was less than 2.4 km (1.5 mi) from the center of the rover's touchdown target after a 563,000,000 km (350,000,000 mi) journey.  Curiosity is a car-sized robotic rover exploring Gale Crater on Mars as part of NASA's Mars Science Laboratory mission (MSL).

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The Landing Site

The descent stage blast pattern around the rover is clearly seen as relatively blue colors (true colors would be more gray). Curiosity landed within Gale Crater, a portion of which is pictured here. The mountain at the center of the crater, called Mount Sharp, is located out of frame to the southeast. North is up. This image was acquired at an angle of 30 degrees from straight down, looking west.

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MSL Landing Site in Gale Crate  HiRISE DTM

The landing site of Curiosity Rover was Gale Crater, in the northwestern part of the Aeolis Region, is of special interest to geologists because it contains a 2–4 km (1.2–2.5 mile) high mound of layered sedimentary rocks.  The mound extends higher than the rim of the crater, so perhaps the layering covered an area much larger than the crater. These layers are a complex record of the past. The rock layers probably took millions of years to be laid down within the crater, then more time to be eroded to make them visible. The 5 km high mound is probably the thickest single succession of sedimentary rocks on Mars.

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Gale Crater rim about 18 km (11 mi) North of the Curiosity Rover on August 9, 2012.

The Aeolis Region is the only Martian Region to have two successful rover landings in the same region.  Did NASA purposely plan these landings or was it by accident that they  both landed  in the same Region ?

 

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Self-Portrait of the Curiosity Rover

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Layers at the Base of Mount Sharp

A chapter of the layered geological history of Mars is laid bare in this postcard from NASA's Curiosity rover. The image shows the base of Mount Sharp, the rover's eventual science destination.  Scientists enhanced the color in one version to show the Martian scene under the lighting conditions we have on Earth, which helps in analyzing the terrain.

 

Gale Crater and Mount Sharp

Aeolis Mons (Mount Sharp): The mountain appears to be an enormous mound of eroded sedimentary layers sitting on the central peak of Gale. It rises 5.5 km (18,000 ft) above the northern crater floor and 4.5 km (15,000 ft) above the southern crater floor, higher than the southern crater rim. The sediments may have been laid down over an interval of 2 billion years, and may have once completely filled the crater. Some of the lower sediment layers may have originally been deposited on a lakebed, while observations of possibly cross-bedded strata in the upper mound suggest Aeolian processes. However, this issue is debated, and the origin of the lower layers remains unclear.

 

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First Chemical Analysis of Martian Soil by Curiosity 

Discoveries of Curiosity 1

Rocks Discovered by Curiosity:

Goulburn, also known as Goulburn Scour, is a rock outcrop on the surface of Aeolis Palus, between Peace Vallis and Aeolis Mons ("Mount Sharp"),  The outcrop is a well-sorted gravel conglomerate, containing well-rounded, smooth, abraded pebbles. Occasional pebbles up to a few centimeters across are embedded in amongst a matrix of finer rounded particles, up to a centimeter across. It has been interpreted as a fluvial sediment, deposited by a vigorously flowing stream, probably between ankle and waist deep. This stream is part of an ancient alluvial fan, which descends from the steep terrain at the rim of Gale crater across its floor.  covered

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Inverted Riverbed in Gale Crater  HiRISE DTM


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First Area of Exploration from video and Rock report given.

Hottah is a rock outcrop on the surface of Aeolis Palus, (between Peace Vallis and Aeolis Mons ("Mount Sharp"), in Gale crater on the planet Mars).  The outcrop is a well-sorted gravel conglomerate, containing well-rounded, smooth, abraded pebbles. Occasional pebbles up to a few centimeters across are embedded in amongst a matrix of finer rounded particles, up to a centimeter across.

Jake Matijevic (or Jake M) is a pyramidal rock on the surface of Aeolis Palus, , in Gale crater on the planet Mars. Analytical studies, performed on the rock by the Curiosity rover in October 2012, suggest the Jake M rock is an igneous rock but found to be high in elements consistent with feldspar, such as sodium, aluminum and potassium, and lower concentrations of magnesium, iron and nickel than other such rocks previously found on Mars. The mineral content and elemental abundance indicates Jake M rock may be a mugearite, a sodium rich oligoclase-bearing basaltic trachyandesite. Igneous rocks similar to the Jake M rock are well known but occur rarely on Earth. On Earth, such rocks form when magma, usually found in volcanoes, rises to the surface, cools and partially solidifies with certain chemical elements, while the warmer liquid magma portion becomes enriched with the left-behind elements.
Bathurst Inlet' Rock on Curiosity's Sol 54, Close-Up View. This is the highest-resolution view that the Mars Hand Lens Imager (MAHLI) on NASA's Mars rover Curiosity acquired of the top of a rock called "Bathurst Inlet." The rover's arm held the camera with the lens only about 1.6 inches (4 centimeters) from the rock. The view covers an area roughly 1.3 inches by 1 inch (3.3 centimeters by 2.5 centimeters). At this distance, the camera provides resolution of 21 microns per pixel. For comparison, the typical resolution in images from the Microscopic Imager cameras on earlier-generation Mars rovers Spirit and Opportunity is about 31 microns per pixel.  The Bathurst Inlet rock is dark gray and appears to be so fine-grained that MAHLI cannot resolve grains or crystals in it. This means that the grains or crystals, if there are any at all, are smaller than about 80 microns in size. Some windblown sand-sized grains or dust aggregates have accumulated on the surface of the rock.
Point Lake Outcrop-One priority target for a closer look by NASA's Mars rover Curiosity before the rover departs the "Glenelg" area east of its landing site is the pitted outcrop called "Point Lake," in the upper half of this image. The outcrop as seen from this angle is about 7 feet (2 meters) wide and 20 inches (50 centimeters) high. The texture, with its voids or cavities, sets Point Lake apart from other outcrops in the vicinity. A closer inspection may yield information about whether it is a volcanic or sedimentary deposit.

 

Glenelg, Mars (or Glenelg Intrigue) is a location on Mars near the Mars Science Laboratory (Curiosity rover) landing site ("Bradbury Landing") in Gale Crater marked by a natural intersection of three kinds of terrain.  The location was named Glenelg by NASA scientists for two reasons: all features in the immediate vicinity were given names associated with Yellowknife in northern Canada, and Glenelg is the name of a geological feature there. Furthermore, the name is a palindrome, and as the Curiosity rover will visit the location twice (once coming, and once going) this was an appealing feature for the name. The original Glenelg is a village in Scotland. The trek to Glenelg will send the rover 400 m (1,300 ft) east-southeast of its landing site. One of the three types of terrain intersecting at Glenelg is layered bedrock, which is attractive as the first drilling target.

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“Shaler" is rock outcrop near the Glenelg Area on Mars - as viewed by the Mast-Cam on the Curiosity rover.

 

Discoveries of Curiosity 2

Rocknest is a sand patch on the surface of Aeolis Palus. The sand patch is downhill from a cluster of dark rocks. NASA determined the patch to be the location for the first use of the scoop on the arm of the Mars Curiosity rover.  The "Rocknest" patch is about 1.5 m (4.9 ft) by 5 m (16 ft).  On October 17, 2012 at "Rocknest", the first X-ray diffraction analysis of Martian soil was performed. The results from the rover's CheMin analyzer revealed the presence of several minerals, including feldspar, pyroxenes and olivine, and suggested that the Martian soil in the sample was similar to the "weathered basaltic soils" of Hawaiian volcanoes. On September 26, 2013, NASA scientists reported the Mars Curiosity rover detected "abundant, easily accessible" water (1.5 to 3 weight percent) in soil samples at the Rocknest region of Aeolis Palus in Gale Crater. In addition, NASA reported the rover found two principal soil types: a fine-grained mafic type and a locally derived, coarse-grained felsic type.

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Sulfate and Clay Strata in Gale Crater  HiRISE DTM

"Darwin,"is a rock outcrop inside Gale Crater. The exposed outcrop at this location, visible in images from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter, prompted Curiosity's science team to select it as the mission's first waypoint during the mission's long trek from the "Glenelg" area to Mount Sharp.  Reddish dust coats much of the surface that is visible , but the patch of rock also offers some bare patches where sand and pebble grains can be seen. Pebbles here are mostly gray, with some white in them. Some grains are somewhat translucent, and some are shiny. Researchers interpret the sand and pebbles in the rock as material that was deposited by flowing water, then later buried and cemented into rock. Curiosity's science team is studying the textures and composition of the conglomerate rock at Darwin to understand its relationship to streambed conglomerate rock found closer to Curiosity's landing site.

Cooperstown is a  rock outcrop ridge.  The drive brought Curiosity to about 262 feet (about 80 meters) from "Cooperstown," an outcrop bearing candidate targets for examination with instruments on the rover's arm.    The ridge extends roughly 100 feet (about 30 meters) from left to right, and it is about 262 feet (about 80 meters) away from the location from where Curiosity was located.  "What interests us about this site is an intriguing outcrop of layered material visible in the orbital images," said Kevin Lewis of Princeton University, Princeton, N.J., a participating scientist for the mission who has been a leader in planning the Cooperstown activities. "We want to see how the local layered outcrop at Cooperstown may help us relate

the geology of Yellowknife Bay to the geology of Mount Sharp."

Dingo Gap:this Martian Valley May Be Curiosity's Route.  The team operating Curiosity has chosen this valley as a likely route toward mid-term and long-term science destinations.  "Dingo Gap," is about 3 feet (1 meter) high in the middle and tapered at south and north ends onto low scarps on either side of the gap.

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Journey of Curiosity as of 2/3/14 Dingo Gap at bottom of Image Shaler at the top

We now leave Curiosity behind and continue to Survey the rest of the Aeolis Region of Mars.  Not far to the south of Gale Crater we come to the next important feature  Lasswitz Crater centered at 3.5°E 9°S.

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Lasswitz Crater

Lasswitz Crater is 111 kilometers in diameter. The Crater is named after  Kurd Lasswitz (German: Kurd Laßwitz,; 20 April 1848 – 17 October 1910) who was a German author, scientist, and philosopher. He has been called "the father of German science fiction.

 

The next large feature we come to is Wien Crater located right next to Lasswitz Crater to the southeast centered at  140°E 10.5 °S.

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Wien Crater

Wien Crater is  120.4 kilometers in diameter.  The Crater is named after Wilhelm Carl Werner Otto Fritz Franz Wien (German); 13 January 1864 – 30 August 1928)who was a German physicist who, in 1893, used theories about heat and electromagnetism to deduce Wien's displacement law, which calculates the emission of a blackbody at any temperature from the emission at any one reference temperature.

 

The Terra Cimmeria Area begins at about 10.5°S but at about 158°E moves southward and stops at about 15°S and continues east to the eastern border of the Aeolis Region.  Just west of Wien Crater we see another part of Terra Cimmeria at 144.8°E 10.6°S.

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Crater Delta in Terra Cimmeria

A small fan-shaped delta is located where a channel meets the floor of this unnamed crater in Terra Cimmeria.

 

The next important feature we come to is Soffen Crater centered at 142° E 25°S.

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Soffen Crater

Soffen Crater is 30 kilometers in diameter.  The Crater is named after Dr. Gerald A. Soffen (February 7, 1926 – November 22, 2000), known as Jerry or Gerry, was a NASA scientist and educator who served in a wide variety of roles for the space agency, primarily dealing with either education or with life sciences—especially the search for life on Mars.

 

To the southeast of Soffen Crater is Molesworth Crater centered at  150°E 28°S.

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.Molesworth Crater

There is  a Central uplift of a smaller Unnamed crater on the floor of Molesworth Crater,   dark sand dunes can be seen on left side of the smaller crater.  Molesworth Crater is a crater in the Aeolis Region of Mars. It is 181 km in diameter and was named after Percy B. Molesworth, a British astronomer (1867–1908).

 

To the northeast of this crater is Graff Crater centered at 153.5° E 21°.

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Graff Crater

Graff Crater is 158 kilometers in diameter.  It was named after Kasimir Romuald Graff (February 7, 1878 – February 15, 1950) who was a German astronomer. He worked as an assistant at the Hamburg Observatory and became a professor at Hamburg in 1916. In 1928 he became director of the Vienna Observatory, Austria. Using a 60 cm telescope, he was very adept in creating planetary maps from visual observations.

 

Not the northeast of Graff Crater is the Hadley Crater which is a crater within a crater.  It is centered at 157.5°E 19°S.

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Hadley Crater

The Mars Express images show that Hadley Crater was struck multiple times by large asteroids and/or comets after its initial formation and subsequent infilling with lava and sediments.  Earlier in 2012 the spacecraft observed the 120 km wide Hadley Crater, providing a tantalizing insight into the Martian crust. The images show multiple subsequent impacts within the main crater wall, reaching depths of up to 2600 m below the surrounding surface.  This region imaged on 9 April 2012 by the High Resolution Stereo Camera on Mars Express shows the crater which lies to the west of the Al-Qahira Vallis in the transition zone between the old southern highlands and the younger northern lowlands. Hadley is named after the British lawyer and meteorologist George Hadley (1685-1768) whose name was also given to the ‘Hadley cell’, a circulation system in the Earth’s atmosphere, which transports heat and moisture from the tropics up to higher latitudes.  The images show that Hadley Crater was struck multiple times by large asteroids and/or comets after its initial formation and subsequent infilling with lava and sediments.  Some of these later impacts have also been partly buried, with subtle hints of a number of crater rims to the west (top), and wrinkle ridges to the north (right side) of the main crater floor as shown in the image`.   The southern (left) side of the crater appears shallower than the opposite side. This difference can be explained by an erosion process known as mass wasting. This is where surface material moves down a slope under the force of gravity.  Mass wasting can be initially started by a range of processes including earthquakes, erosion at the base of the slope, ice splitting the rocks or water being introduced into the slope material, In this case there is no clear indication which process caused it, or over what timescales this may have occurred.

 

The next feature we come to is northeast of Hadley Crater-  Al-Qahira Vallis an outflow channel beginning at about 160°E heading on a northeasterly course extending as far north as 165°E 15°S.

 

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Al-Qahira  Vallis

The Al-Qahira Valles is 155 kilometers long a and for the Arabic word for Mars.

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Megabreccia in a Terra Cimmeria Impact Crater

 

"Megabreccia" is a term we use to describe jumbled, fragmented blocks of rock larger than 1 meter across, in a matrix of finer-grained materials. It's the result of energetic processes, typically from an impact event.  This image is located in northern Terra Cimmeria, near the "shore" of Elysium Planitia. The closest named feature is Al-Qahira Vallis, to the northwest.

 

The next important feature we come to is Boeddicker Crater centered at 162°E 15°S.

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Boeddicker Crater

Boeddicker Crater is a crater in the Aeolis Region of Mars, located at 15° south latitude and 162° east longitude. It is 109 km in diameter and was named after Otto Boeddicker, a German astronomer (1853–1937).

 

North of Boeddicker Crater we enter the Elysium Planitia basin. The Elysium Planitia, located in the Elysium and Aeolis Regions, is a broad plain that straddles the equator of Mars, centered at 3.0°N 154.7°E. It lies to the south of the volcanic province of Elysium, the second largest volcanic region on the planet, after Tharsis.  A 2005 photo of a locale within Elysium Planitia at 5° N, 150° E by the Mars Express spacecraft shows what may be ash-covered water ice. The volume of ice is estimated to be 800 km (500 mi) by 900 km (560 mi) in size and 45 m (148 ft) deep, similar in size and depth to the North Sea. The ice is thought to be the remains of water floods from the Cerberus Fossae fissures about 2 to 10 million years ago. The surface of the area is broken into 'plates' like broken ice floating on a lake. Impact crater counts show that the plates are up to 1 million years older than the gap material, showing that the area solidified much too slowly for the material to be basaltic lava.  The Elysium Planitia covers an area of roughly 3000 kilometers.

 

 

Elysium Planitia in the Aeolis Region

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