Small Pale Red Planet Issue 2 Phase 7

 

Syrtis Major Region

MC-13

The Region covers longitudes 270° to 315° west and latitudes 0° to 30° north on Mars.  Syrtis Major is an old shield volcano with a central depression that is elongated in a north-south direction. It contains the calderas Meroe Patera and Nili Patera.

 

Topographical Map of the Syrtis Major Region

The name Syrtis Major is derived from the classical Roman name Syrtis Major for the Gulf of Sidra on the coast of Libya (classical Cyrenaica).  Syrtis Major was the first documented surface feature of another planet. It was discovered by Christian Huygens, who included it in a drawing of Mars in 1659.

Image of the Syrtis Major Region

The central part of the Region is dominated by dark dust and lava flows of the Syrtis Major Planum region. These lava flows are partly bounded to the east by a large depression, Isidis basin, which contains smooth plains, and to the west and north by heavily cratered and moderately faulted highlands. Latitude range 0 to 30 degrees, longitude range -90 to -45 degrees.

Syrtis Major is of great interest to geologists because several types of igneous rocks have been found there with orbiting spacecraft. Besides basalt, dacite and granite have been found there. Dacite originates under volcanoes in magma chambers. Dacites form at the top of the chamber, after heavy minerals (olivine and pyroxene) containing iron and magnesium have settled to the bottom. Granite is formed by an even more complex process.  Some areas of Syrtis Major contain large amounts of the mineral olivine. Olivine turns into other minerals very rapidly in the presence of water, so a high abundance of olivine suggests that for a long time little water has been there.

Starting from the Northeast corner of the Region we head south and encounter the Flammarion Crater at  25 N and 48 E. 

Layers in Flammarion Crater.

The crater was named after Nicolas Camille Flammarion (26 February 1842 – 3 June 1925) a French astronomer and author.  The crater is 173 km in diameter.

Passing Flammarion Crater we head south into the uplands of the Terra Sabaea.  The next Crater we come to is Schöner Crater.

Schöner Crater is located at  20.1°N 309.5°W.  It is 195 km in diameter and named after           Johannus Schöner (January 16, 1477 in – January 16, 1547). He was a priest, astronomer, astrologer, geographer, cosmographer, cartographer, mathematician, globe and scientific instrument maker.

Continuing south we next come to Cusus Valles.

Rocky layers around Cusus Valles

As we travel further southward the elevation increases and southeast of the Cusus Valles we come to Leighton Crater which is closer to the equator.

Possible Carbonate-Rich Terrain in Central Structure of Leighton Crater

Leighton Crater is located at 3.06°N 302.32°W and is 69 km in diameter so it is a smaller crater than the ones we have been coming across.  The crater was named after Robert B. Leighton (September 10, 1919 – March 9, 1997) who was a prominent American experimental physicist.  Research published in October 2010, described a large deposit of carbonate rocks found inside Leighton Crater at a level that was once buried 4 miles (6 km) below the surface. Finding carbonates in an underground location strongly suggests that Mars was warmer and had more atmospheric carbon dioxide and ancient seas. Because the carbonates were near silicate minerals and clays hydrothermal systems like the deep-sea vents on Earth may have been present.

Going north from there we go along the border of Terra Sabaea and Syrtis Major Planum (or Plains).  There are not many named craters in the area until we come to the huge Antoniadi Crater located at  21.5 degrees north latitude and 61.1 degrees east longitude.

Antoniadi Crater with Inverted Branching Stream Channels

Antoniadi Crater is 394 km in diameter and was named after Eugène Michel Antoniadi (Greek: Εὐγένιος Μιχαὴλ Αντωνιάδης; 1 March 1870,  – 10 February 1944, ) who was a Greek astronomer.

Exploring Antoniadi Crater

Probably connected to the northern rim of Antoniadi Crater is the Anquakuh Vallis.

Auquakuh Vallis in Syrtis Major. Location is 28.2 degrees north latitude and 299.2 degrees west longitude.

Anquakuh Vallis is an ancient river valley in the Syrtis Major Region on Mars.  It is 312 km long, and was named for the word for 'Mars' in Quechua (Inca).  At one time a dark layer covered the whole area, now only a few pieces remain as buttes.  Many places on Mars have buttes that are similar to buttes on Earth, such as the famous ones in Monument Valley, Utah. Buttes are formed when most of a layer(s) of rocks are removed from an area. Buttes usually have a hard, erosion-resistant cap rock on the top. The cap rock causes the top of a butte to be flat.

Further to the East but coming from the north also is the Huo Hsing Vallis.

Dikes in Huo Hsing Vallis in which liquid rock once flowed.

Huo Hsing Vallis is an ancient river valley in the Syrtis Major Region of Mars at 30.5° north latitude and 293.4° west longitude. It is about 318 km long and was named after the word for "Mars" in Chinese. Some crater floors in the Syrtis Major area show elongated ridges in a lattice-like pattern. Such patterns are typical of faults and breccia dikes formed as a result of an impact. The ridges are found where there has been enhanced erosion. Pictures on this page show examples of these dikes. Water may flow along faults. The water often carries minerals that serve to cement rock materials thus making them harder. Later when the whole area undergoes erosion the dikes will remain as ridges because they are more resistant to erosion. This discovery may be of great importance for future colonization of Mars because these types of faults and breccia dikes on earth are associated with key mineral resources. Perhaps, when people live on Mars these areas will be mined as they are on earth.

Similar Dikes located on Earth in Colorado

Dikes or narrow ridges occur in some places on Mars. They may be formed by different means, but some are probably caused by molten rock moving underground, cooling into hard rock, then being exposed by the erosion of softer, surrounding materials. Such a feature is termed a dike. The discovery on Mars of dikes that were formed from molten rock is highly significant because dikes indicate the existence of intrusive igneous activity. On the Earth such activity is associated with precious metals like gold, silver, and tellurium.  Mapping the presence of dikes allows us to understand how magma (molten rock under the ground) travels and where it could have interacted with surrounding rock, thus producing valuable ores. Deposits of important minerals are also made by dikes and other igneous intrusions heating water which then dissolves minerals that are deposited in cracks in nearby rock. One would expect a great deal of intrusive igneous activity to occur on Mars because it is believed there is more igneous activity under the ground than on top, and Mars has many huge volcanoes.

Huo Hsing Vallis Ridges, as seen by HiRISE. Ridges may be caused by water moving along faults.

Going south from there we come to Baldet Crater.

Megabreccia on Floor of Baldet Crater

Baldet Crater is located at 23.0°N 294.6°W and is 180 km in diameter.  It was named after Ferdinand Baldet (16 March 1885 – 8 November 1964) who was a French astronomer.

To the southeast in the Syrtis Major Planum we come to Toro Crater located at 17°N and 71.7°E.  It is a small crater about 40 km in diameter.

Exploring the floor of Toro Crater

Toro Crater may have experienced hydrothermal alteration, producing diverse minerals. The mineral diversity leads to diverse color in HiRISE, especially when enhanced as in this sub image. In general the blue and green colors indicate unaltered minerals like pyroxene and olivine, whereas the warmer colors indicate alteration into clays and other minerals. The linear north-south trending features are windblown dunes that are much younger than the bedrock.

To the southwest of Toro Crater is  Arnus Vallis.

Layers in Arnus Vallis

Sand dunes are found all over Mars. Often sand dunes will form in low areas, for example on the floor of ancient river valleys.   Dunes on the floor of Arnus Vallis, an old river valley are visible in a picture above. Dunes in valleys on Mars usually lie at right angles to the valley walls.  Arnus Vallis is an ancient river valley in the Syrtis Major Region of Mars, located at 14.1° north latitude and 289.5° west longitude. It is 280 km long and was named after the classical and present day Arno River in Tuscany, Italy (previously named Arena Rupes).

In an elongated valley- like area to the southwest of Arnus Vallis are the two volcanoes of the Region located at an elevation at 0-1000 meters.  The surrounding terrain is between 1000-3000 meters high. Here we are still in the Syrtis Major Planum.  The two volcanoes are the Nili Patera and Meroe Patera mentioned earlier.

THEMIS daytime infrared image mosaic showing the central portion of the broad, low-lying shield volcanoes in the Syrtis Major Planum, just north of the equator in the eastern hemisphere of Mars. The calderas Nili Patera and Meroe Patera are visible to the upper left and lower right of center, respectively.

Here there is  a 350 by 150 km north-south elongated central depression containing the calderas Nili Patera and Meroe Patera, which are about 2 km deep. The floors of the calderas are not elevated relative to the terrain of the surrounding Syrtis Major Planum. The floor of Nili Patera is the less cratered, and therefore the younger, of the two. While most of the rock is basaltic, dacite has also been detected in Nili Patera. Satellite gravity field measurements show a positive gravity anomaly centered on the caldera complex, suggesting the presence of a 600x300 km north-south elongated extinct magma chamber below, containing dense minerals (probably mainly pyroxene, with olivine also possible) that precipitated out of magma before eruptions. Crater counts date the Syrtis Major Region to the early Hesperian epoch; it postdates formation of the adjacent Isidis impact basin.

Going southeast from the volcanoes on a 45 degree angle we come to the Libya Montes in the southeast corner of the Syrtis Major Region on the Equator.  The Libya Montes are a highland terrain on Mars up-lifted by the giant impact that created the Isidis basin to the north.  During 1999, this region became one of the top two that were being considered for the canceled Mars Surveyor 2001 Lander. The Isidis basin is very ancient. Thus, the Libya Montes that form the southern Isidis basin rim contain some of the oldest rocks available at the Martian surface, and a landing in this region might potentially provide information about conditions on early Mars.  It’s Coordinates are 1.44°N 88.23°E.

The Libya Montes

After they were formed by the Isidis impact, (estimated to have occurred between 3.7-3.1 billion years ago) the Libya Montes were subsequently modified by a large variety of processes, including fluvial activity, wind erosion and impact cratering. In particular, precipitation induced surface runoff and groundwater seepage resulted in the formation of fluvial landforms, i.e., dense valley networks, broad and elongated valleys, delta deposits, alluvial fans, open-basin paleo lakes and coastlines.

As you enter the Libya Montes from the west you come across the Zarqa Valles.

The Zarqa Valles is located at 0.16°N 80.82°E.  It is 490 km long and is named after the Zarqa River (Arabic: نهر الزرقاء‎, Hebrew: נחל יבוק, Yabok river)  the second largest tributary of the lower Jordan River.

The Libya Montes is also known to have the second face on Mars,  that I have mentioned earlier. The Libya Montes has a face-like formation that appears even when viewed at different angles and with different sun angles. It can be found in the Mars Global Surveyor, MOC narrow-angle image M02-03051. Also in HiRISE image ESP 018368 1830 (non-map projected) and ESP 018223 1830—a stereo pair that allows 3D terrain data to be generated. Like the  the first Face on Mars, it is an example of pareidolia.  That is the imagined perception of a pattern where it does not actually exist, as in considering Mars to have human features.

Sometimes called "The Crowned Face"

The Isidis Planitia is a plain located inside a giant impact basin on Mars, centered at  12.9°N 87.0°E. It covers a little over a quarter of the Eastern part of the Syrtis Major Region. It is the third biggest obvious impact structure on the planet after the Hellas and Argyre basins – it is about 1,500 km (930 mi) in diameter. Due to dust coverage, it typically appears bright in telescopic views, and was mapped as a classical albedo feature, the Isidis area was visible by telescope in the pre-spacecraft era.

Topographical Map of the Isidis Basin

Very Recent Small Crater in Isidis Planitia

Around the Isidis basin magnesium carbonate was found by MRO. This mineral indicates that water was present and that it was not acidic, pH conditions more favorable for the evolution of life.  The name "Isidis Planitia" follows the earlier name Isidis Region ("Isis' Region"). Isis is the Egyptian goddess of heaven and fertility.

Jezero Crater is located on the western edge of the Isidis Planitia. Once flooded with water, the crater contains a fan-delta deposit rich in clays.  In several Slavic languages including Bosnian, Croatian, Czech, Serbian, and Slovenian, the word Jezero means "lake".  Its location is 18.4°N 282.4°W and it is 49 km in diameter.

Proposed MSL Landing Site in Jezero Crater

Layered Valley Connected to the Eastern Part of Jezero Crater

Nili Fossae is a group of large, concentric grabens  that have been eroded and partly filled in by sediments and clay-rich ejecta from a nearby giant impact crater, the Isidis basin.  It is located at approximately 22°N, 75°E, and has an elevation of −0.6 km (−0.37 mi). Nili Fossae was on the list of potential landing sites of the Mars Science Laboratory, arriving in 2012, but was dropped before the final four sites were determined. A large exposure of olivine is located in Nili Fossae. In December 2008, NASA's Mars Reconnaissance Orbiter found that rocks at Nili Fossae contain carbonate minerals, a geologically significant discovery. Other minerals found by MRO are aluminum smectite, iron/magnesium smectite, hydrated silica, kaolinite group minerals, and iron oxides.  NASA scientists discovered that Nili Fossae is the source of plumes of methane raising- the question is whether this source originates from biological sources. Researchers in July 2010 suggested that carbonate bearing rocks found in the Nili Fossae region of Mars are made up of hydro thermally altered ultramafic rocks. Consequently, hydrothermal activity would have provided sufficient energy for biological activity. Evidence of living organisms could have been preserved. Possible evidence of 'buried life' was recently found at Nili Fossae.

Nili Fossae as seen by CRISM. Top left: location of observation. Bottom left: context of observation. Top right: yellow-brown areas denote olivine, bright green areas denote phyllosilicates and purple areas pyroxene. Bottom right: approximate true-color view of the target area.

The coordinates for Nili Fossae are 22.57°N 76.8°E and it covers an area 667 km. CRISM is the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) is a visible-infrared spectrometer aboard the Mars Reconnaissance Orbiter searching for mineralogical indications of past and present water on Mars.  CRISM is being used to identify locations on Mars that may have hosted water, a chemical considered important in the search for past or present extraterrestrial life. In order to do this, CRISM is mapping the presence of minerals and chemicals that may indicate past interaction with water - low-temperature or hydrothermal. These materials include iron and oxides, which can be chemically altered by water, and phyllosilicates and carbonates, which form in the presence of water. All of these materials have characteristic patterns in their visible-infrared energy and are readily seen by CRISM. In addition, CRISM is monitoring ice and dust particulates in the Martian atmosphere to learn more about its climate and seasons.

The CRISM Instrument

Exploring the Nili Fossae Area

In the Southern part of Nili Fossae we come to Hargraves Crater.

Hargraves Crater in Southern Nili Fossae

It is located at 20.76°N 284.36°W and  is 68 km in diameter.  It was named after Robert B. Hargraves (August 11, 1928 – March 21, 2003) who was an American geologist who worked as a professor at Princeton University.

Going to the northeast of Nili Fossae we come to the Arena Colles area.

Arena Colles Phyllosilicate Deposit

The Arena Colles is composed of a group of hills and knobs.  It is my theory that wherever there is a large Phyllosilicate or clay deposit there is a good possibility that through chemical reactions with local bacteria methane gas can be produced. and that  may be the case here.  The bacteria could be an undiscovered variety that would be producing the gas.   The Arena Colles area is located at 24°N and 81°E.

Located in the center of the Arena Colles area is Peridier Crater.

Linear Ridges and Fans on Floor of Peridier Crater

Peridier Crater is located at 25.7°N 276.2°W it is 100 km in diameter.  It was named after Julien Péridier (1882 – April 19, 1967) a French electrical engineer and amateur astronomer.

Small Pale Red Planet Issue 2 Phase 6

 

Arabia Region

MC-12

 

Topographical Map of the Arabia Region

This Region contains part of the classic area of Mars known as Arabia. It lies on the boundary between the young northern plains and the old southern highlands. The Arabia Region covers the area from 315° to 360° west longitude and 0° to 30° north latitude.

Image of the Arabia Region

The surface of the Arabia Region appears to be very old because it has a high density of craters, but it is not near as high in elevation as typical old surfaces. On Mars the oldest areas contain the most craters; the oldest period is called the Noachian after the Region Noachis. The Arabia Region contains many buttes and ridges.

Layered butte in Arabia Terra, as seen by HiRISE under HI Wish program. Location is 29.7 N and 6.4 E.

Some believe that during certain climate changes an ice-dust layer was deposited; later, parts were eroded to form buttes. Some outflow channels are found in Arabia, namely Naktong Vallis, Locras Valles, Indus Vallis, Scamander Vallis, and Cusus Valles.  The Arabia Region has many unnamed craters and a very high crater population some of them are very large.

Layers in Arabia Terra  as seen by HiRISE under HI Wish program

Starting from the northeast corner of the Region we enter into  the Arabia Terra area which covers about a third of the Arabia Region-especially in the western part.  Arabia Terra is a large upland region in the north of Mars in that lies mostly in the Arabia Region. It is densely cratered and heavily eroded. This battered topography indicates great age, and Arabia Terra is presumed to be one of the oldest terrains on the planet. It covers as much as 4,500 km (2,800 mi) at its longest extent, centered roughly at  19.79°N 30°E with its eastern and southern regions rising 4 km (13,000 ft) above the north-west. Alongside its many craters, canyons wind through the Arabia Terra, many emptying into the large northern lowlands of the planet, which borders Arabia Terra to the north.

 

Northern Arabia Terra

The first crater of any consequence that we come to is Maggini Crater.  It is located at 28.0°N 350.6°W and is 143 km in diameter.

.Maggini Crater

Mentore Maggini (February 6, 1890 – May 8, 1941) was an Italian astronomer.  He was director of the Collurania Observatory and is best known for his maps of Mars and the work on binary stars. This crater on Mars was named in his honor.

Going further south  we come to Gill Crater.

Layers in Gill Crater wall, as seen by HiRISE under HI Wish program. Location is 16.5 N and 5.4 E.

Layers in mesa, as seen by HiRISE under HI Wish program also in Gill Crater.

Meridiani Planum in Southwest Arabia Region corner on the Equator

It is believed a source of Martian Methane comes from this region.    One study with the Planetary Fourier Spectrometer in the Mars Express spacecraft found possible methane in three areas of Mars, one of which was in the Arabia Region. One possible source of methane is from the metabolism of living bacteria. However, a recent study indicates that to match the observations of methane, there must be something that quickly destroys the gas, otherwise it would be spread all through the atmosphere instead of being concentrated in just a few locations.  Its destruction would be caused by the sun’s radiation and cosmic rays. There may be something in the soil that oxidizes the gas before it has a chance to spread which seems doubtful   Life forms could  be producing this gas as a by- product of their metabolism under the ground.

Martian Methane Production

Trace amounts of methane in the atmosphere of Mars were discovered in 2003 and verified in 2004. As methane is an unstable gas, its presence indicates that there must be an active source on the planet in order to keep such levels in the atmosphere. It is estimated that Mars must produce 270 tons of methane a year, but asteroid impacts are believed to account for only 0.8% of the total methane production. Although geologic sources of methane such as serpentinization are possible, the lack of current volcanism, hydrothermal activity or hotspots are not favorable for this form of geologic methane. It has been suggested that the methane was produced by chemical reactions in meteorites, driven by the intense heat during entry through the atmosphere. Although research published in December 2009 ruled out this possibility,  research published in 2012 suggest that a source may be organic compounds on meteorites that are converted to methane by ultraviolet radiation.  The existence of life in the form of microorganisms such as methanogens is among the possible, but as yet unproven sources. If microscopic Martian life is producing the methane, it likely resides far below the surface, where it is still warm enough for liquid water to exist.  Since the 2003 discovery of methane in the atmosphere, some scientists have been designing models and in vitro experiments testing growth of methanogenic bacteria on simulated Martian soil, where all four methanogen strains tested produced substantial levels of methane, even in the presence of 1.0wt% perchlorate salt. The results reported indicate that the perchlorates discovered by the Phoenix Lander would not rule out the possible presence of methanogens on Mars.  In June 2012, scientists reported that measuring the ratio of hydrogen and methane levels on Mars may help determine the likelihood of life on Mars. According to the scientists, "...low H2/CH4 ratios (less than approximately 40) indicate that life is likely present and active." Other scientists have recently reported methods of detecting hydrogen and methane in other extraterrestrial atmospheres as well.

Next we head to the northeast to Capen Crater.  The Mars Reconnaissance Orbiter showed deformation bands in Capen Crater, located in the Arabia Region. Deformation bands are small faults with very small displacements. They often proceed large faults. They develop in porous rocks, like sandstone. They can restrict and/or change the flow of fluids like water and oil. The bands on Mars are a few meters wide and up to a few kilometers long. They are caused by the compression or stretching of underground layers. Erosion of overlying layers make them visible at the surface. Capen Crater was unnamed before the discovery of deformation bands. It was named for Charles Capen, who studied Mars at JPL's Table Mountain Observatory in California and at Lowell Observatory in Arizona.

The group of lines running up and down in the image are believed to be deformation bands. They can be thought of as small faults.

Capen Crater is located at 6.57°N 345.73°W. and  it is 70 km in diameter. A large basin, maybe from an impact, was produced early in Martian history. It was so early that Mars still had a magnetic field generated by movements in a liquid core. The present day Arabia Region possesses a remnant magnetism from that ancient era.  Therefore it might be possible for atmospheric gases to exist in a higher concentration in this area in a elongated bubble due to this remnant of magnetism in this area.

Going to the northeast we come to Henry Crater.  Henry Crater is a large crater in the Arabia quadrangle of Mars, located at 10.9° north latitude and 336.7° west longitude. It is 171 kilometers (106 mi) in diameter and was named after the brothers Paul-Pierre Henry and Mathieu-Prosper Henry, both of whom were French telescope makers and astronomers. Mounds in craters like Henry are formed by the erosion of layers that were deposited after the impact.

Mound in Henry Crater

To the north and west of  Henry crater we enter the southern part of Arabia Terra.

Complex system of ridges in Arabia Terra

Southern Arabia Terra

Northeast of Henry Crater is Pasteur Crater also in the Arabia Region of Mars, located at 19.4° north latitude and 335.5° west longitude. It is 113 kilometers (70 mi) in diameter and was named after Louis Pasteur, a French chemist.  Dark sand dunes are clustered in the southwest of the crater. The orientation of the Barchan dunes suggest that they were generated by northeasterly winds. The source of the dune's sand appears to be local. Upwind of the dunes there is a small crater, Euphrates, within Pasteur crater that may have excavated sediments. The dark sediments have formed a patch at Euphrates' base. HiRISE imagery of the intracrater dunes within Pasteur crater over 1 Martian year indicate that the dunes are active with sand movement in a southwesterly direction.

Erosion in Pasteur Crater

Going to the northeast of that Crater we come to the Cassini Crater and just on it’s northern rim is Luzin Crater. Cassini Crater on Mars is named in honor of the Italian astronomer Giovanni Cassini.  The crater is approximately 415 km in diameter and can be found at 327.9°W and 23.8°N. It is in the Arabia Region of Mars.  Recent research leads scientists to believe that some of the craters in Arabia may have held huge lakes. Cassini Crater probably once was full of water since its rim seems to have been breached by the waters. Both inflow and outflow channels have been observed on its rim. The lake would have contained more water than Earth's Lake Baikal, our largest freshwater lake by volume.

Layers in the Cassini Crater Floor

 

Crater on the floor of Cassini crater, as seen by HI rise. The location is 24 degrees north latitude and 327.9 degrees west longitude.

Just to the southeast of Cassini Crater is the Indus Vallis Location is 18.8 degrees north and 39.8 degrees East.

Indus Vallis

Indus Vallis is a river valley in the Arabia Region of Mars. It is 307 km long and was named after the ancient and modern name for a river in Pakistan.

 

Geological History of the Arabia Region:
Recent studies, reported in the journal Icarus, have suggested that the area underwent several phases in its formation:

1. A large basin, maybe from an impact, was produced early in Martian history. It was so early that Mars still had a magnetic field generated by movements in a liquid core. Present day Arabia possesses a remnant magnetism from that ancient era.
2. Sediments flowed into the basin. Water entered the basin.
   
3. Because Tharsis, on the other side of Mars, became so massive, the area around Arabia was pushed out. As it bulged upward, there was increased erosion which exposed old layers. When portions of a planet that can be subject to erosion rise, there is greatly increased erosion; Earth's Grand Canyon became very deep because it was eroded into a high plateau.
   
4. Over the following 4 billion years, the area was modified by various geological processes. Central peaks and ejecta shapes indicate that parts of Arabia are still water enriched.

Continuing on a more southerly route from Cassini we come to a bigger valley the Scamander Vallis.

Northeast Extent of Scamander Vallis

Following Scamander Vallis southward we enter the Terra Sabaea area.  The Terra Sabaea area is the uplands of the Arabia Region and occupy almost a third of the Arabia Region mostly in the  southeast part.  Almost ESE of Scamander Vallis is Tikhonravov Crater.

Location is 12.8 N and 34.9 E.  Pedestal craters and layers in Tikhonravov Crater. in Arabia Region, as seen by Mars Global Surveyor (MGS), under the MOC Public Targeting Program. Layers may form from volcanoes, the wind, or by deposition under water. Some researchers believe this crater once held a massive lake.

How Pedestal Craters are formed

Tikhonravov Crater: is a large, eroded crater in the Arabia Region of Mars. It is 386.0 kilometers (240 mi) in diameter and was named after Mikhail Tikhonravov, a Russian rocket scientist. Tikonravov is believed to have once held a giant lake that drained into the 4500 km long Naktong-Scamander-Mamers lake-chain system. An inflow and outflow channel has been identified.  Recent research leads scientists to believe that some of the craters in Arabia may have held huge lakes. Cassini Crater and Tikonravov Crater probably once were full of water since their rims seem to have been breached by water. Both inflow and outflow channels have been observed on their rims. Each of these lakes would have contained more water than Earth's Lake Baikal, our largest freshwater lake by volume. The watersheds for lakes in Arabia seem to be too small to gather enough water by precipitation alone; therefore it is thought that much of their water came from groundwater.

Continuing southward into Terra Sabaea we follow the Scamander Vallis  into Arago Crater.

 

Elevation Map of Arago Crater

The crater’s location is 11.5°N 28.6°E. diameter 145 km.  Named after  Dominique F. Arago a French astronomer (1786-1853).

From there we follow another river valley southward the  Naktong Vallis.  It is an ancient river valley in the Arabia Region of Mars, located at 5.3 degrees north latitude and 327.1 degrees west longitude. It is 494 km long and was named after a river in Korea.  Naktong Vallis is part of the Naktong/Scamander/Mamers Valles lake-chain system that is comparable in length of Earth's largest system, like  the Missouri-Mississippi Rivers.

Naktong Vallis

East of Naktong Vallis at about 3°N is Janssen Crater.

Rock Outcrop in Janssen Crater

Janssen Crater is located at 3.3°N and 38.2°E.  Named after Pierre, Jules Janssen a Mathematician and Physicist  Born in Paris, in February 22nd 1824, and died in Meudon, in December 23rd 1907.

Terraforming Mars Phase 2:

The Surface Gravity & Magnetosphere on Mars is 38% of that on Earth. It is not known if this is enough to prevent the health problems associated with weightlessness.  Additionally, the low gravity (and thus low escape velocity) of Mars may render it more difficult for the planet to retain an atmosphere when compared to the more massive Earth and Venus. Earth and Venus are both able to sustain thick atmospheres, even though they experience more of the solar wind that is believed to strip away planetary volatiles (the atmosphere). Continuing sources of atmospheric gases on Mars might therefore be required to ensure that an atmosphere sufficiently dense for humans is sustained in the long term.  Mars lacks a magnetosphere, which poses challenges for mitigating solar radiation and retaining atmosphere. It is believed that fields detected on the planet are remnants of a magnetosphere that collapsed early in the planet's history.  The lack of a magnetosphere is thought to be one reason for the planet's thin atmosphere. Solar wind-induced ejection of Martian atmospheric atoms has been detected by Mars-orbiting probes. Venus, however, clearly demonstrates that the lack of a magnetosphere does not preclude a dense atmosphere. Earth abounds with water because its ionosphere is permeated with a magnetosphere. The hydrogen ions present in its ionosphere move very fast due to their small mass, but they cannot escape to outer space because their trajectories are deflected by the magnetic field. Venus has a dense atmosphere, but only traces of water vapor (20 ppm) because it has no magnetic field. The Martian atmosphere also loses water to space. Earth's ozone layer provides additional protection. Ultraviolet light is blocked before it can dissociate water into hydrogen and oxygen. Since little water vapor rises above the troposphere and the ozone layer is in the upper stratosphere, little water is dissociated into hydrogen and oxygen.  The Earth's magnetic field is 31 µT. Mars would require a similar magnetic field intensity to similarly offset the effects of the solar wind at a distance farther from the Sun. The technology for inducing a planetary scale magnetic field does not currently exist.

The Dream Phase 2 …………..

Small Pale Red Planet Issue 2 Phase 5

Oxia Palus Region

MC-11

 

Topographical Map of the Oxia Palus Region

 

The Region covers the region of 0° to 45° west longitude and 0° to 30° north latitude on Mars. Mars Pathfinder landed in the Oxia Palus Region on July 4, 1997.

Image of Oxia Palus Region

 

Crater names in Oxia Palus are a Who's Who for famous scientists. Besides Galilaei and DaVinci, some of the people who discovered the atom and radiation are honored there: Curie, Becquerel, and Rutherford. Mawrth Vallis was strongly considered as a landing sites for NASA's next Mars rover, the Mars Science Laboratory. This Region contains abundant evidence for past water in such forms as river valleys, lakes, springs, and chaos areas where water flowed out of the ground. A variety of clay minerals have been found in Oxia Palus. Clay is formed in water, and it is good for preserving microscopic evidence of ancient life. Recently, scientists have found strong evidence for a lake located in the Oxia Palus quadrangle that received drainage from Shalbatana Vallis.

We begin our survey from the northwest corner of the Region in the Chryse Planitia which extends into this Region.  The area that we first encounter is called the Xanthe Dorsa.  Dorsa is a Latin word that is associated with the physiology of animals but on Mars it refers to hilly regions, rock outcroppings and other features that poke up from the crust of the planet.  It can be a series of hills, buttes and so on.

Landforms in Xanthe Dorsa

Going south to about 16°N and 317°E we come to a major river valley called Shalbatana Vallis, which goes south over the Equator into the Margaritifer Sinus Region.

Shalbatana Vallis in the Infrared  This location was shot of the lower part at about 5°N.

Shalbatana Vallis form HiRISE

Shalbatana Vallis is an ancient water-worn river valley on Mars, located in the Oxia Palus Region at 7.8° north latitude and 42.1° west longitude. It is the westernmost of the southern Chryse outflow channels. Beginning in a zone of chaotic terrain, at 0° latitude and 46° W longitude, it ends in Chryse Planitia.

Possible Lake Margin in Shalbatana Vallis

Shalbatana Vallis contains the first definitive evidence of a Martian shoreline. This shoreline was part of an ancient lake 80 square miles (210 km2) in size and 1,500 feet (460 m) deep. The study carried out with HiRISE images indicates that water formed a 30 miles (48 km) long canyon that opened up into a valley, deposited sediment, and created a delta. This delta and others around the basin imply the existence of a large, long-lived lake. Of special interest is evidence that the lake formed after the warm, wet period was thought to have ended. So, lakes may have been around much longer than previously thought.

Shalbatana Vallis travels through another area that is called Xanthe Terra.  Xanthe Terra: is a large area on Mars, centered just north of the Martian equator. Its coordinates are: 3°N 312°E and it covers 2465 km at its broadest extent. Its name means "golden-yellow land." It is in the Lunae Palus quadrangle and the Oxia Palus quadrangle. Images from Mars Express, Mars Global Surveyor, and the Mars Reconnaissance Orbiter have revealed ancient river valleys and deltas. The deltas show many thin layers just as deltas on Earth. Scientists speculate that features in Xanthe Terra show evidence of precipitation on early Mars.

Chaos Region in Xanthe Terra

Next we come to  Hydroates Chaos on the Equator.  There are many chaos areas in the Oxia Palus Region of Mars.

Mesas and Buttes of Hydroates Chaos

Hydroates Chaos is an equatorial region of chaotic terrain located near some of the large outflow channels on Mars. Chaotic terrain near the outflow channels (ancient flood channels) is thought to form when ices beneath the surface rapidly become liquid or gaseous and escapes, and the remaining solid material collapses.  Chaotic terrain is called "chaotic" because it consists of a large jumble of randomly shaped mesas (hills) and troughs. Many regions of chaotic terrain are located at the head (start) of the outflow channels, suggesting that the origins of the two classes of feature might be related to each other.  The mesa located in the center of the image has elongated depressions that might be evidence of past fluvial activity.

 

Tiu Valles

Tiu Valles is an outflow channel in the Oxia Palus quadrangle of Mars, located at 15.9° North and 35.7° West.  It is 1,720 km long and was named after the word for "Mars" in old English (West Germanic).  It seems to get its start in the south in the Hydroates Chaos.  It head northwards and passes to the west of the Mojave Crater which is bordered on the East by the Chryse Chaos area.

Mojave Crater

Mojave Crater which is located between the Chryse Chaos and the Tiu Valles and has alluvial fans that look remarkably similar to landforms in the Mojave Desert in the American southwest. Fans inside and around the outside of Mojave Crater on Mars are a perfect match to Earth's alluvial fans. As on Earth, the largest rocks are near the mouths of the fans. Because channels start at the top of ridges, it is believed they were formed by heavy downpours. Researchers have suggested that rain may have initiated by impacts.  Mojave Crater is approximately 2,604 meters (1.63 miles) deep. Based on its diameter and depth, researchers believe it is very young. It has not been around long enough to accumulate material and start to fill. It is giving scientists great insight into impact processes on Mars since it is so fresh.

Central Peak of Sagan Crater

Sagan Crater is an impact crater in the Oxia Palus Region of Mars. It is located at 10.8° N and 30.7° W. It is named after Carl E. Sagan, an American astronomer (1934–1996). Dr. Sagan was a founder of the Planetary Society.

Just to the northwest lies Masursky Crater.  The Chryse Chaos has become part  of the crater floor.

Chaotic Terrain in Masursky Crater

Going north from here we come to the Ares Vallis.  It too is a very long ancient Martian river valley that crosses the Equator and extends into the next Region to the south.

The Ares Vallis Region

The Mars Pathfinder is an American spacecraft that landed a base station with a roving probe on Mars in 1997. It consisted of a lander, renamed the Carl Sagan Memorial Station, and a lightweight (10.6 kg/23 lb.) wheeled robotic Mars rover named Sojourner.  Launched on December 4, 1996 by NASA aboard a Delta II booster a month after the Mars Global Surveyor was launched, it landed on July 4, 1997 on Mars's Ares Vallis, in the Chryse Planitia in the Oxia Palus Region. The lander then opened, exposing the rover which conducted many experiments on the Martian surface. The mission carried a series of scientific instruments to analyze the Martian atmosphere, climate, geology and the composition of its rocks and soil.

Robotic Rover Sojourner

The landing site was an ancient flood plain in Mars's northern hemisphere called "Ares Vallis" ("the valley of Ares", the ancient Greek equivalent of the ancient Roman deity Mars) and is among the rockiest parts of Mars. Scientists chose it because they found it to be a relatively safe surface to land on and one that contained a wide variety of rocks deposited during a catastrophic flood. After the landing, at the coordinates 19.13°N 33.22°W succeeded,   the landing site received the name The Carl Sagan Memorial Station in honor of the astronomer.

The Mars Pathfinder

Types of rocks:  Results of Mars Pathfinder's Alpha Proton X-ray Spectrometer indicated that some rocks in the Oxia Palus quadrangle are like Earth's andesites. The discovery of andesites shows that some Martian rocks have been re-melted and reprocessed. On Earth, Andesite forms when magma sits in pockets of rock while some of the iron and magnesium settle out. Consequently, the final rock contains less iron and magnesium and more silica. Volcanic rocks are usually classified by comparing the relative amount of alkalis (Na2O and K2O) with the amount of silica (SiO2). Andesite is different than the rocks found in meteorites that have come from Mars.

The Sojourner Rover is taking its Alpha Proton X-ray Spectrometer measurement of the Yogi Rock. Note: Sojourner Rover was the rover part of the Mars Pathfinder. It rolled off of the lander. This picture was taken by the lander.

By the time that final results of the mission were described in a series of articles in the Journal Science (December 5, 1997), it was believed that the rock Yogi contained a coating of dust, but was similar to the rock Barnacle Bill another rock that was examined. Calculations suggest that the two rocks contain mostly the minerals orthopyroxene (magnesium-iron silicate), feldspars (aluminum silicates of potassium, sodium, and calcium), quartz (silicon dioxide), with smaller amounts of magnetite, ilmenite, iron sulfide, and calcium phosphate.  By taking multiple images of the sky at different distances form the sun, scientists were able to determine that size of the particles in the pink haze was about 1 micrometer in radius. The color of some soils was similar to that of an iron oxyhydroxide phase which would support a warmer and wetter climate in the past  Pathfinder carried a series of magnets to examine the magnetic component of the dust. Eventually, all but one of the magnets developed a coating of dust. Since the weakest magnet did not attract any soil, it was concluded that the airborne dust did not contain pure magnetite or just one type of maghemite. The dust probably was an aggregate possibly cemented with ferric oxide (Fe2O3). Using much more sophisticated instruments, Mars Spirit Rover found that magnetite could explain the magnetic nature of the dust and soil on Mars. Magnetite was found in the soil and that the most magnetic part of the soil was dark. Magnetite is very dark.  Using Doppler tracking and two-way ranging, scientists added earlier measurements from the Viking landers to determine that the non-hydrostatic component of the polar moment of inertia is due to the Tharsis bulge and that the interior is not melted. The central metallic core is between 1300 km and 2000 km in radius.

 

Sunset at the Mars Pathfinder location

 

 

 

 

Difference in size of spacecraft through wheel size comparison: Sojourner, Mars Exploration Rovers (Opportunity & Spirit), Mars Science Laboratory.

Just to the north the Ares Valles joins the Tiu Valles. Tiu Valles Ridges, were seen by HiRISE. The ridges were probably formed by running water. The Tiu Valles runs just west of where the Mars Pathfinder landed and heads north of there for a considerable distance.

Streamlined Form at the Confluence of Tiu Valles and Ares Vallis

Towards the northern end of the Tiu Valles is Kipini Crater.

Small Very Fresh Crater on South End of Kipini Crater Floor

Kipini Crater is an impact crater in the Oxia Palus Region of Mars. It is located at 26.1° N and 31.6° W It is named after a Town in Kenya.

Heading back down south again we come to Mawth Vallis. Mawrth Vallis (Mawrth means "Mars" in Welsh) is a valley on Mars located at 22.3°N, 343.5°E with an elevation approximately two kilometers below datum. It is an ancient water outflow channel with light-colored clay-rich rocks. Mawrth Vallis is one of the oldest valleys on Mars. It was formed in and subsequently covered by layered rocks, from beneath which it is now being exhumed.

Mawrth Valles

Marwrth Vallis as seen by Themis. The location is 22.3 degrees north latitude and 15.9 degrees west longitude.

Mawrth Vallis Geodiversity

Mawrth Vallis was strongly considered as a landing site for NASA's next Mars rover, the Mars Science Laboratory. This Region contains abundant evidence for past water in such forms as river valleys, lakes, springs, and chaos areas where water flowed out of the ground. A variety of clay minerals have been found in Oxia Palus. Clay is formed in water, and it is good for preserving microscopic evidence of ancient life.

Just west of Mawth Vallis is McLaughlin Crater.   McLaughlin Crater is an old crater in the Oxia Palus Region of Mars, located at   21.9°N 337.63°E. It is 90.92 km (56.50 mi) in diameter and 2.2 km (1.4 mi) deep. The crater was named after Dean B. McLaughlin, an American astronomer (1901-1965). The Mars Reconnaissance Orbiter has found evidence that the water came from beneath the surface about 2 billion years ago and remained long enough to make carbonate-related clay minerals found in layers.

McLaughlin Crater

These photos of a huge crater on Mars suggest water may lurk in crevices under the planet's surface, hinting that life might have once lived there, and raising the possibility that it may live there still, researchers say.  Future research looking into the chances of life on Mars could shed light on the origins of life on Earth, scientists added.  The discovery came from a study of images by NASA's powerful Mars Reconnaissance Orbiter that revealed new evidence of a wet underground environment  on the Red Planet. The images focused on the giant McLaughlin Crater, which is about 57 miles (92 kilometers) wide and so deep that underground water appears to have flowed into the crater at some point in the distant past. Today, the crater is bone-dry but harbors clay minerals and other evidence that liquid water filled the area in the ancient past.  "Taken together, the observations in McLaughlin Crater provide the best evidence for carbonate forming within a lake environment instead of being washed into a crater from outside," said study lead author Joseph Michalski, of the Planetary Science Institute in Tucson, Arizona.

Going straight south and crossing the Ares Valles upstream we come to the Margaritifer Terra.  Margaritifer Terra is an ancient, heavily cratered region of Mars. It is located in a region both south and north of the equator and covers 2600 km at its widest extent. The area reveals "chaos terrain", outflow channels, and alluvial plains that are indicative of massive flooding. Wind erosion patterns are also in evidence. The region within the terra shows some of the highest valley network densities on the planet.  Then at 13°N and 338°E the Ares Valles comes to a fork and  just due south of that fork at a short distance is the Aram Chaos.

The Aram Chaos is in an ancient impact crater near the Martian equator, close to Ares Vallis. About 280 kilometers (170 mi) across, Aram Chaos lies in a region called Margaritifer Terra, where many water-carved channels show that floods poured out of the highlands onto the northern lowlands ages ago. The Thermal Emission Imaging System (THEMIS) on the Mars Odyssey orbiter found gray crystalline hematite on the floor of Aram. Hematite is an iron-oxide mineral that can precipitate when ground water circulates through iron-rich rocks, whether at normal temperatures or in hot springs. The floor of Aram contains huge blocks of collapsed, or chaotic, terrain that formed when water or ice was catastrophically removed.

Erosion in Aram Chaos, as seen by Themis. Image location is 2.8 degrees north latitude and 21.1 degrees west longitude. Picture taken with Mars Odyssey's THEMIS.

In Aram Chaos, however, the released water stayed mostly within the crater's ramparts, eroding only a small, shallow outlet channel in the eastern wall. Several minerals including hematite, sulfate minerals, and water-altered silicates in Aram suggests that a lake probably once existed within the crater. Because forming hematite requires liquid water, which could not long exist without a thick atmosphere, Mars must have had a much thicker atmosphere at some time in the past, when the hematite was formed.

Blocks in Aram showing possible source of water, as seen by THEMIS. This is the Chaos that some claim was an artificially made city.

Aram Chaos Crater

Going east we cross the Ares Valles again and come to Crommlin  Crater, that is a part of a region called Meridiani Planum which also straddles the Equator.  Crommlin Crater is a little over 100 kilometers (62 miles) across and contains a mound of layered rock deposits. Layering in geologic materials is interesting because it represents a record of deposition over time. By studying such layered sequences, scientists attempt to tell what the local climate and environment were like in the past.  Crommlin Crater is an impact crater in the Oxia Palus Region of Mars. It is located at 5.1° north and 10.2° west. It was named after Andrew C. Crommlin, a British astronomer (1865–1939).

Crommlin Crater Layered Deposit, as seen by HiRISE. The color blue in the photo is a false color.

Crommlin Crater contains a large mound that shows dozens of regular spaced layers.

^{Crommlin Crater contains a layered mound that is higher than its rim. This drawing shows how it was formed when much of the material was eroded away.  Many craters on Mars have a mound or mass of material in their centers that are remains of deposited sediments.}

Going northeast from here we come to Vernal Crater also located in Meridiani Planum. A study of images taken with the High Resolution Imaging Science Experiment (HiRISE) on the Mars Reconnaissance Orbiter strongly suggests that hot springs once existed in Vernal Crater, in the Oxia Palus Region. These springs may have provided a long-time location for life. Furthermore, mineral deposits associated with these springs may have preserved traces of Martian life.

Hydrothermal springs in Vernal crater, as seen by HiRISE. Location is 5.6 degrees north latitude and 4.4 degrees west longitude.

In Vernal Crater on a dark part of the floor, two light-toned, elliptical structures closely resemble hot springs on the Earth. They have inner and outer halos, with roughly circular depressions. A large number of hills are lined up close to the springs. These are thought to have formed by the movement of fluids along the boundaries of dipping beds. The picture above shows these springs. One of the depressions is visible. The discovery of opaline silica by the Mars Rovers, on the surface also suggests the presence of hot springs.  Opaline silica is often deposited in hot springs. Scientists proposed this area should be visited by the Mars Science Laboratory.

Going north of there we enter another region called Arabia Terra. Arabia Terra continues to the east into its own Region of the same name.  For now we are only interested in the part that is in Oxia Palus.

Cliffs and canyons in Arabia Terra, as seen by HiRISE.

To the north we come to  Becquerel  Crater .  Becquerel is a 167 km-diameter crater at 22.1°N, 352.0°E on Mars, in Arabia Terra. It is named after Antoine H. Becquerel.  Photographs by the Mars Global Surveyor revealed layered sedimentary rocks in the crater. The layers appear to be only a few meters thick and show little variations in thickness. Recent studies with HiRISE have determined the exact thickness of the layers. The 66 layers measured showed one group of layers to average 3.6 meters (12 ft) and another group to average 36 meters (118 ft) in thickness. Patterns like this are usually produced on Earth through the effects of water; volcanic deposits would not produce ash or lava flows of such regular thickness and in any event there are no nearby volcanic vents.

Becquerel Crater

Layers in Becquerel Crater

There are cyclic variations in the thickness of the exposed sedimentary layers, possibly indicating cyclic variations in environmental conditions while the sediment was being laid down.  Most of the layers are parallel to each other, suggesting they formed by vertical settling, but a few are cross-bedded, indicating that at the time that the layers were deposited the sediment was transported along the ground surface by wind or water. The sedimentary material appears to be easily eroded and active wind erosion may be continuing to the current day.

^{Central Uplift of Curie Crater}

Curie Crater is an impact crater in the Oxia Palus Region of Mars, located at 29.1° N and 4.8° W. It is 114.1 km in diameter and was named after Pierre Curie, a French physicist-chemist (1859-1906).

Close-up of layers in central mound of Curie Crater, as seen by HiRISE.

The terraforming of Mars is the hypothetical process by which Martian climate, surface, and known properties would be deliberately changed with the goal of making large areas of the environment more hospitable to human habitation, thus making human colonization much safer and more sustainable.  The concept relies on the assumption that the environment of a planet can be altered through artificial means.  In addition, the feasibility of creating a planetary biosphere on Mars is undetermined. There are several proposed methods, some of which present prohibitive economic and natural resource costs, and others which may be currently technologically achievable. In many respects, Mars is the most Earth-like of all the other planets in the Solar System. Indeed, it is thought that Mars once did have a more Earth-like environment early in its history, with a thicker atmosphere and abundant water that was lost over the course of hundreds of millions of years. Given the foundations of similarity and proximity, Mars would make the most efficient and effective terraforming target in the Solar System. 

The dream…..