Lunae Palus Region
MC-10
We start into this region from it’s northwest corner and head southward The Lunae Palus Region covers the area from 45° to 90° west longitude and 0° to 30° north latitude on Mars.
Topographical Map for the Lunae Palus Region
The Viking program comprised a pair of American space probes sent to Mars, Viking 1 and Viking 2. Each spacecraft was composed of two main parts: an orbiter designed to photograph the surface of Mars from orbit, and a lander designed to study the planet from the surface. The orbiters also served as communication relays for the landers once they touched down. It was the most expensive and ambitious mission ever sent to Mars, with a total cost of roughly US$1 billion. It was highly successful and formed most of the body of knowledge about Mars through the late 1990s and early 2000s. Viking 1 landed in this Region as indicated by the map above.
Image of Lunae Palus Region
The first feature we come to in the northwest corner of the region is the Uranius Fossae at 25°N.
Sample of Discontinuous Ridge in the Uranius Fossae Region.
Going to the southeast we come to Fesenkov Crater.
Central Peak of Fesenkov Crater
Fesenkov Crater is an impact crater in the Lunae Palus Region of Mars. It is located at 21.8° N and 86.7° W. It was named after Vasilii G. Fesenkov, a Russian astrophysicist (1889–1972). The crater is 87.38 km in diameter.
Going northeast from there, we come to the Labeatis Fossae. The Labeatis Fossae is a large trough in the Lunae Palus Region of Mars, located at 25.5° N and 84.1° W. It is 1,560 km long and named after a previously named feature at 30N, 75W.
.Close Up off the Labeatis Fossae
Going southeast of Labeatis Fosse, we come to Nilus Chaos at 25.97°N and 282.09 E. It appears to be part of a gully.
Nilus Chaos in the Infrared
Going southwest of there, we come to the Uranius Dorsum at 23.26°N and 284.08°E.
Uranius Dorsum
The Uranius Dorsum is a group of hills running from the southwest to the northeast across our path as we head southeast.
Going due south of here, we find ourselves in a wide valley that must have at one time contained a large volume of water, in its center we come to the Echus Montes.
The Echus Montes
The Echus Montes is a large mountain on Mars at 7.81°N 282.05°E. It is located in the Lunae Palus Region. It is 258.91 km long and just to the east on the east side of the Canyon there is the Echus Chaos
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The Echus Chaos
The Echus Chaos is located at 10.78°N and 285.2°E and is 473 km in diameter.
South of this location, we enter the Echus Chasma itself. The Echus Chasma is approximately 100 km long and 10 km wide, with valleys ranging in depth from around 1 km to 4 km. It is the source region of the Kasei Valles outflow channel, which extends northward from it. It is situated just west of Hebes Chasma, to which it does not connect.
Layers in Echus Chasma
Mars, like the Earth, appears to be a layered planet, which has major implications for processes that have formed the geology we see today on the surface. Anyone who has ever gone to the Grand Canyon and seen the layering along the canyon walls may know that each layer is a record for each period in history. Such as a time in the past when the region was covered with a sea and sedimentary and/ or volcanic layers were emplaced. The arrangement of layers relative to each other, such as when one layer lies on top of another or one layer cuts through another, tells us about the stratigraphy, which is how geologists determine the sequence of processes that occurred over time in a particular area.
Another view of Echus Chasma
The Lunae Planum is an area that is bordered on the west by the Echus outflow channel that leads to the Kasei Vallles. To the east, it is bordered by the Maja Valles, which begins south of the Lunae Palus Region in Coprates Region in the Juventae Chasma. The Lunae Planum (Latin for Lunar Plains) is located at 10.38 N 294.0 E and covers an area of 1800 km. This Plains area has many hills, valleys, and craters. The following video covers the area from the equator to the Kasei Valles.
The Lunae Planum Area
Next, we come to the great outflow channel Kasei Valles. Vallis (plural Valles) is the Latin word for valley. It is used in planetary geology for the naming of landform features on other planets. Vallis (plural Valles) was used for old river valleys that were discovered on Mars, when the first probes were sent to Mars. The Viking Orbiters caused a revolution in our ideas about water on Mars; huge river valleys were found in many areas. Orbiting cameras showed that floods of water broke through dams, carved deep valleys, eroded grooves into bedrock, and traveled thousands of kilometers. There is evidence of water all over the planet.
Kasei Vallis in Lunae Palus with channels labeled. Location is 26.5 degrees north latitude and 70.1 degrees west longitude. This picture was taken by the Mars 2001 Odyssey Thermal Emission Imaging System (THEMIS).
Kasei Valles is one of the most significant features of the Lunae Palus region, Kasei Valles, is one of the largest outflow channels on Mars. Like other outflow channels, it was carved by liquid water, probably during gigantic floods. Kasei Valles is about 2,400 kilometers (1,500 mi) long. Some sections of Kasei Valles are 300 kilometers (190 mi) wide. It begins in Echus Chasma, near the Valles Marineris, and empties into Chryse Planitia, not far from where Viking 1 landed.
Topographical Map of Kasei Vales and Vicinity
Sacra Mensa, a large tableland, divides Kasei into northern and southern channels. It is one of the longest continuous outflow channels on Mars. At around 20° north latitude Kasei Valles splits into two channels, called Kasei Vallis Canyon and North Kasei Channel. These branches recombine at around 63° west longitude.
Cataracts in N. Kasei Valles Channel
Going northeast from there following the outflow channels, we come to the Lobo Valles. It is located at 26°N and 296°E.
Lobo Valles
This part of the Lobo Valles is believed to have been made by both lava and water flowing through the area. Following this area to the southeast is another large mesa with large crater in its center the name of the crater is Sharonov. After that, the outflow channels lead out into the Chryse Planitia. The Chryse Planitia lies partially in the Lunae Palus Region and partially in the Oxia Palus Region. It is 1600 km in diameter and with a floor 2.5 km below the average planetary surface altitude, and is thought to be an ancient impact basin; it has several features in common with Lunar Maria, such as wrinkle ridges. The density of impact craters in the 100 to 2,000 meters (330 to 6,600 ft) range is close to half the average for Lunar Maria. Chryse Planitia shows evidence of water erosion in the past, and is the bottom end for many outflow channels from the southern highlands as well as from Valles Marineris and the flanks of the Tharsis bulge. It is one of the lowest regions on Mars (2 to 3 kilometers (1.2 to 1.9 mi) below the mean surface elevation of Mars), so water would tend to flow into it. In our terms it is below Sea Level.
Possible Future Landing Site with Mounds in Chryse Planitia
Going directly south from Sharonov Crater, we come to Conso Crater.
Canso Crater, as seen by HiRISE. Location is 21.3 degrees north latitude and 299.4 degrees east longitude. Image was taken by the Mars Reconnaissance Orbiter's HiRISE.
It lies about 450 kilometers west of the Viking 1 lander, slightly northeast of Lunae Planum, and west of Chryse Planitia, in the Lunae Palus Region. The crater is named after Canso, a fishing town in Nova Scotia. The name was officially adopted in 1988 by the International Astronomical Union's Working Group for Planetary System Nomenclature.
Directly east, we come to more Valles. The first of which is the Bahran Valles.
Bahram Vallles
The Bahram Vallis is an ancient river valley in the Lunae Palus quadrangle of Mars at 20.7° north latitude and 57.5° west longitude. It is about 302 km long and named after the word for ‘Mars’ in Persian. Bahram Vallis is located midway between Vedra Vallis and lower Kasei Valles. It is a single trunk valley, with scalloped walls in some places. The presence of streamlined erosional features on its floor shows that fluid was involved with its formation.
Animation of the Bahram Valles Area
Going a short distance from there, we come to the Vedra Valles and the Maumee Valles –one located below the other. The Vedra Vallis is an ancient river valley in the Lunae Palus quadrangle of Mars, located at 19.4° N and 55.6° W. It is 115.0 km long and named after an ancient river in Great Britain. Together with other ancient river valleys, it has provided strong evidence for a great deal of running water on the surface of Mars.
Vedra and Maumee Valles and Vicinity
Maumee Vallis is an ancient river valley in the Lunae Palus Region of Mars, located at 19.7° N and 53.2° W. It is 350.0 km long and named after a North American river in Indiana and Ohio. Together with other ancient river valleys, it has provided strong evidence for a great deal of running water on the surface of Mars.
Below these two Vallles, we come to the Maja Valles it is a large, ancient outflow channel in the Lunae Palus Region on Mars. Its location is 12.6° north latitude and 58.3° west longitude. The name is a Nepali word for "Mars". Maja Valles begins in the Juventae Chasma. Parts of the system have been partially buried by thin volcanic debris. Maja Valles ends in the Chryse Planitia. It is one of the longest of the Valles as its source is in the south in the Coprates Region.
Streamlined islands in Maja Vallis, as seen by Viking.
Great amounts of water were required to carry out the erosion shown in this Viking image of a small part of Maja Valles. Image is located in Lunae Palus Region.
Huge outflow channels were found in many areas by the Viking Orbiters. They showed that floods of water broke through dams, carved deep valleys, eroded grooves into bedrock, and traveled thousands of kilometers.
Just east of the Maja Vales is the Ister Chaos in the beginning of the Uplands of Xanthe Terra. Ister Chaos is a broken up area in the Lunae Palus Region of Mars. It is located at 13.0° N and 56.4° W. It is 103.4 km across and named after a classical albedo feature at 10N, 56W.
Ister Chaos
The specific causes of chaos terrain are not yet well understood. A number of different astrogeological forces have been offered as causes of chaos terrain. On Mars chaos terrain is believed to be associated with the release of huge amounts of water. The Chaotic features may have collapsed when water came out of the surface. Martian rivers begin with a Chaos region. A chaotic region can be recognized by a rat's nest of mesas, buttes, and hills, chopped through with valleys that in places look almost patterned. Sometimes like, they are artificially made. Some parts of this chaotic area have not collapsed completely—they are still formed into large mesas, so they may still contain water ice beneath the surface. Chaotic terrain occurs in numerous locations on Mars, and always gives the strong impression that something abruptly disturbed the ground. Chaos terrain regions formed long ago. We have nothing like it here on Earth.
Nanedi Valles is located in the southeast corner of the Lunae Palus Region. The location is 5.8 N and 311 E. this Valles is about 18,5 km wide at its widest.
Nanedi Valles
Nanedi Valles: is a large valley in the Lunae Palus Region of Mars, located at 4.9° N and 49.0° W. It is 508.0 km long and named for the word for “planet” in Sesotho, the national language of Lesotho, Africa. Nanedi Valles is located between Shalbatana Vallis and upper Maja Valles. It is 4 km wide at its northern end. Its shape is similar to that of Nirgal Vallis, being very sinuous and having only a few short branches.
Northeast of Nanedi Valles is Hypanis Vallis a 270 km valley in Xanthe Terra on Mars at 11ºN, 314ºE. It appears to have been carved by long-lived flowing water, and a significant river delta exists at its outlet into the lowlands.
Hypanis Vallis
Hypanis Vallis, in the Lunae Palus Region, was one of the sites proposed as a landing site for the Mars Science Laboratory. The aim of the Mars Science Laboratory is to search for signs of ancient life. It is hoped that a later mission could then return samples from sites identified as probably containing remains of life. A smooth, flat twelve-mile area was needed to bring the craft safely down. Geologists hope to examine places where water once accumulated. They would like to examine sediment layers.
After that, we enter Chryse Planitia (Greek, "Golden Plain") again. It is a smooth circular plain in the northern equatorial region of Mars close to the Tharsis region to the west, centered at 26.7°N 320.0°E. The elevation generally goes down from the Tharsis Ridge to Chryse Planitia. Kasei Vallis, Maja Valles, and Nanedi Valles appear to run from high areas (Tharsis Ridge) into Chryse Planitia. On the other side of Chryse, to the east, the land gets higher.
Distinctive Contact Between Deposits in South Chryse Planitia
The next major feature we come to as we head north is the Santa Fe Crater. Santa Fe Crater is an impact crater with gullies in the Lunae Palus Region of Mars, located at 19.5° North and 48.0° W. It is 20.5 km in diameter and was named after Santa Fe, New Mexico.
Santa Fe Crater
Close up of gullies in crater, as seen by HiRISE.
The Viking spacecraft after orbiting Mars for more than a month and returning images used for landing site selection, the orbiters and landers detached; the Viking landers then entered the Martian atmosphere and soft-landed at the sites that had been chosen. The Viking 1 lander touched down on the surface of Mars on July 20, 1976 at 22.4°N 47.5°W. It was the first robot spacecraft to successfully land on the Red Planet.
A view from Viking 1
Viking Program Scientific Objectives:
1. Obtain high-resolution images of the Martian surface.
2. Characterize the structure and composition of the atmosphere and surface.
3. Search for evidence of life on Mars
Trenches dug into the Martian surface by the Viking I Lander. The color is accurate with the pink sky. The trenches are in the "Sandy Flats" area of the landing site at Chryse Planitia. The boom holding the meteorology sensors is at left.
Replica of Viking Lander
What would it look like walking around the landing site: The sky would be a light pink. The dirt would also appear pink. Rocks of many sizes would be spread about. One large rock, named "Big Joe", is as big as a banquet table. Some boulders would show erosion due to the wind. There would be many small sand dunes that are still active. The wind speed would typically be 7 meters per second (16 miles per hour). There would be a hard crust on the top of the soil similar to a deposit, called caliche, which is common in the U.S. Southwest. Such crusts are formed by solutions of minerals moving up through soil and evaporating at the surface.
Viking 1 Video
Analysis of Soil: The soil resembled those produced from the weathering of basaltic lavas. The tested soil contained abundant silicon and iron, along with significant amounts of magnesium, aluminum, sulfur, calcium, and titanium. Trace elements, strontium, and yttrium, were detected. The amount of potassium was 5 times lower than the average for the Earth's crust. Some chemicals in the soil contained sulfur and chlorine that were like those remaining after the evaporation of seawater. Sulfur was more concentrated in the crust on top of the soil then in the bulk soil beneath. The sulfur may be present as sulfates of sodium, magnesium, calcium, or iron. A sulfide of iron was also possible.
Search for Life: Viking did three experiments looking for life. The results were surprising and interesting. Most scientists now believe that the data were due to inorganic chemical reactions of the soil. However, a few still believe the results were due to living organic reactions. Not finding any organics was unusual since meteorites raining on Mars for 5 billion years or so would surely bring some organics. Moreover, dry areas of Antarctica do not have detectable organic compounds either, but they have organisms living in the rocks. Mars has almost no ozone layer, like the Earth, so UV light sterilizes the surface and produces highly reactive chemicals such as peroxides that would oxidize any organic chemicals at least on the surface of the planet. One of the designers of the Labeled Release experiment, Gilbert Levin, believes his results are a definitive diagnostic for life on Mars. However, this result is disputed by many scientists, who argue that superoxidant chemicals in the soil could have produced this effect without life being present. An almost consensus discarded the Labeled Release data as evidence of life, because the gas chromatograph & mass spectrometer, designed to identify natural organic matter, did not detect organic molecules. The results of the Viking mission concerning life are considered by the general expert community, at best, as inconclusive.
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