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Arsinoes Chaos
Arsinoes Chaos is a chaos terrain in the Margaritifer Sinus quadrangle on Mars. It is 200 km in diameter. Its location is 7.66 °S and 27.9 °W. Arsinoes Chaos was named after Arsinoe, a queen of ancient Egypt, daughter of Ptolemy and Berenice. Chaos terrain on Mars is distinctive; nothing on Earth compares to it. Chaos terrain generally consists of irregular groups of large blocks, some tens of kilometres across and a hundred or more meters high. The tilted and flat topped blocks form depressions hundreds of metres deep. A chaotic region can be recognized by a rat's nest of mesas, buttes, and hills, chopped through with valleys which in places look almost patterned. Some parts of this chaotic area have not collapsed completely—they are still formed into large mesas, so they may still contain water ice. Some buttes and mesas in Arsinoes display layering. Many places on Mars show rocks arranged in layers. Rock can form layers in a variety of ways. Volcanoes, wind, or wate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Martian Chaos Terrain
Chaos terrain on Mars is distinctive; nothing on Earth compares to it. Chaos terrain generally consists of irregular groups of large blocks, some tens of kilometers across and a hundred or more meters high. The tilted and flat topped blocks form depressions hundreds of metres deep. A chaotic region can be recognized by a rat's nest of mesas, buttes, and hills, chopped through with valleys which in places look almost patterned. Some parts of this chaotic area have not collapsed completely—they are still formed into large mesas, so they may still contain water ice. Chaos regions formed long ago. By counting craters (more craters in any given area means an older surface) and by studying the valleys' relations with other geological features, scientists have concluded the channels formed 2.0 to 3.8 billion years ago. Locations The greatest concentrations of chaotic terrain are in the same locations as giant, ancient river valleys. Because so many large channels seem to originate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Margaritifer Sinus Quadrangle
The Margaritifer Sinus quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. The Margaritifer Sinus quadrangle is also referred to as MC-19 (Mars Chart-19). The Margaritifer Sinus quadrangle covers the area from 0° to 45° west longitude and 0° to 30° south latitude on Mars. Margaritifer Sinus quadrangle contains Margaritifer Terra and parts of Xanthe Terra, Noachis Terra, Arabia Terra, and Meridiani Planum. The name of this quadrangle means "pearl bay" after the pearl coast at Cape Comorin in South India. This quadrangle shows many signs of past water with evidence of lakes, deltas, ancient rivers, inverted channels, and chaos regions that released water. Margaritifer Sinus contains some of the longest lake-chain systems on Mars, perhaps because of a wetter climate, more groundwater, or some of each factor. The Samara/Himera lake-chain system is about 1800 km long; the Parara ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arsinoe II
Arsinoë II ( grc-koi, Ἀρσινόη, 316 BC – unknown date between July 270 and 260 BC) was a Ptolemaic queen and co-regent of the Ptolemaic Kingdom of ancient Egypt. She was given the Egyptian title "King of Upper and Lower Egypt", making her pharaoh as well. Arsinoe was Queen of Thrace, Anatolia, and Macedonia by marriage to King Lysimachus. She became co-ruler of the Ptolemaic Kingdom upon her marriage to her brother, Pharaoh Ptolemy II Philadelphus. Life Early life Arsinoë was the first daughter of Pharaoh Ptolemy I Soter, founder of the Hellenistic state of Egypt, and his second wife Berenice I of Egypt. She was maybe born in Memphis, but was raised in the new city of Alexandria, where her father moved his capital. Nothing is known of her childhood or education, but judging from her later life as patron of scholars and noted for her learning, she is estimated to have been given a high education. Her brothers were tutored by intellectuals hired by their fathers, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Butte
__NOTOC__ In geomorphology, a butte () is an isolated hill with steep, often vertical sides and a small, relatively flat top; buttes are smaller landforms than mesas, plateaus, and table (landform), tablelands. The word ''butte'' comes from a French language, French word meaning Hillock, knoll (but of any size); its use is prevalent in the Western United States, including the Southwestern United States, southwest where ''mesa'' (Spanish language, Spanish for "table") is used for the larger landform. Due to their distinctive shapes, buttes are frequently landmarks in plains and mountainous areas. To differentiate the two landforms, geographers use the rule of thumb that a mesa has a top that is wider than its height, while a butte has a top that is narrower than its height. Formation Buttes form by weathering and erosion when hard caprock overlies a layer of less resistant rock (geology), rock that is eventually worn away. The harder rock on top of the butte resists erosion. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesa
A mesa is an isolated, flat-topped elevation, ridge or hill, which is bounded from all sides by steep escarpments and stands distinctly above a surrounding plain. Mesas characteristically consist of flat-lying soft sedimentary rocks capped by a more resistant layer or layers of harder rock, e.g. shales overlain by sandstones. The resistant layer acts as a caprock that forms the flat summit of a mesa. The caprock can consist of either sedimentary rocks such as sandstone and limestone; dissected lava flows; or a deeply eroded duricrust. Unlike ''plateau'', whose usage does not imply horizontal layers of bedrock, e.g. Tibetan Plateau, the term ''mesa'' applies exclusively to the landforms built of flat-lying strata. Instead, flat-topped plateaus are specifically known as '' tablelands''.Duszyński, F., Migoń, P. and Strzelecki, M.C., 2019. ''Escarpment retreat in sedimentary tablelands and cuesta landscapes–Landforms, mechanisms and patterns.'' ''Earth-Science Reviews, no. 10 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salts
In chemistry, a salt is a chemical compound consisting of an ionic assembly of positively charged cations and negatively charged anions, which results in a compound with no net electric charge. A common example is table salt, with positively charged sodium ions and negatively charged chloride ions. The component ions in a salt compound can be either inorganic, such as chloride (Cl−), or organic, such as acetate (). Each ion can be either monatomic, such as fluoride (F−), or polyatomic, such as sulfate (). Types of salt Salts can be classified in a variety of ways. Salts that produce hydroxide ions when dissolved in water are called '' alkali salts'' and salts that produce hydrogen ions when dissolved in water are called '' acid salts''. ''Neutral salts'' are those salts that are neither acidic nor basic. Zwitterions contain an anionic and a cationic centre in the same molecule, but are not considered salts. Examples of zwitterions are amino acids, many metabolites, pept ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mineral
In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid chemical compound with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed. (2011): Minerals'; p. 1. In the series ''Geology: Landforms, Minerals, and Rocks''. Rosen Publishing Group. The geological definition of mineral normally excludes compounds that occur only in living organisms. However, some minerals are often biogenic (such as calcite) or are organic compounds in the sense of chemistry (such as mellite). Moreover, living organisms often synthesize inorganic minerals (such as hydroxylapatite) that also occur in rocks. The concept of mineral is distinct from rock, which is any bulk solid geologic material that is relatively homogeneous at a large enough scale. A rock may consist of one type of mineral, or may be an aggregate of two or more different types of minerals, spacially segregated into disti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HiWish
HiWish is a program created by NASA so that anyone can suggest a place for the HiRISE camera on the Mars Reconnaissance Orbiter to photograph. It was started in January 2010. In the first few months of the program 3000 people signed up to use HiRISE. The first images were released in April 2010. Over 12,000 suggestions were made by the public; suggestions were made for targets in each of the 30 quadrangles of Mars. Selected images released were used for three talks at the 16th Annual International Mars Society Convention. Below are some of the over 4,224 images that have been released from the HiWish program as of March 2016. Glacial features Some landscapes look just like glaciers moving out of mountain valleys on Earth. Some have a hollowed-out appearance, looking like a glacier after almost all the ice has disappeared. What is left are the moraines—the dirt and debris carried by the glacier. The center is hollowed out because the ice is mostly gone. These supposed alp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mars Reconnaissance Orbiter
''Mars Reconnaissance Orbiter'' (MRO) is a spacecraft designed to study the geology and climate of Mars, provide reconnaissance of future landing sites, and relay data from surface missions back to Earth. It was launched on August 12, 2005, and reached Mars on March 10, 2006. In November 2006, after five months of aerobraking, it entered its final science orbit and began its primary science phase. The cost to develop and operate MRO through the end of its prime mission in 2010 was . The spacecraft continues to operate at Mars, far beyond its intended design life. Due to its critical role as a high-speed data-relay for ground missions, NASA intends to continue the mission as long as possible, at least through the late 2020s. Pre-launch After the twin failures of the '' Mars Climate Orbiter'' and the Mars Polar Lander missions in 1999, NASA reorganized and replanned its Mars Exploration Program. In October 2000, NASA announced its reformulated Mars plans, which reduced the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HiRISE
High Resolution Imaging Science Experiment is a camera on board the ''Mars Reconnaissance Orbiter'' which has been orbiting and studying Mars since 2006. The 65 kg (143 lb), US$40 million instrument was built under the direction of the University of Arizona's Lunar and Planetary Laboratory by Ball Aerospace & Technologies Corp. It consists of a 0.5m (19.7 in) aperture reflecting telescope, the largest so far of any deep space mission, which allows it to take pictures of Mars with resolutions of 0.3m/pixel (1ft/pixel), resolving objects below a meter across. HiRISE has imaged Mars exploration rovers on the surface, including the ''Opportunity'' rover and the ongoing ''Curiosity'' mission. History In the late 1980s, of Ball Aerospace & Technologies began planning the kind of high-resolution imaging needed to support sample return and surface exploration of Mars. In early 2001 he teamed up with Alfred McEwen of the University of Arizona to propose such ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yardang
A yardang is a streamlined protuberance carved from bedrock or any consolidated or semiconsolidated material by the dual action of wind abrasion by dust and sand and deflation (the removal of loose material by wind turbulence.) Yardangs become elongated features typically three or more times longer than wide, and when viewed from above, resemble the hull of a boat. Facing the wind is a steep, blunt face that gradually gets lower and narrower toward the lee end. Yardangs are formed by wind erosion, typically of an originally flat surface formed from areas of harder and softer material. The soft material is eroded and removed by the wind, and the harder material remains. The resulting pattern of yardangs is therefore a combination of the original rock distribution, and the fluid mechanics of the air flow and resulting pattern of erosion. Names The word itself is of Turkic origin, meaning ‘steep bank’, as this type of spectacular landscapes rising are best developed in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transverse Aeolian Ridges
Transverse aeolian ridges (TARs) are visually bright features commonly found in topographic depressions on Mars. These small-scale and relict bedforms were first seen in narrow-angle images from the Mars Orbiter Camera (MOC) and were called “ridges” to preserve both dunes and ripples as formative mechanisms. While TARs are widespread on Mars, their formation, age, composition, and role in past Martian sediment cycles remain poorly constrained. Aeolian bedforms Aeolian bedforms are typically classified into either ripples or dunes based on their morphologies and formative mechanisms. Dunes are larger (>0.5 m or taller on Earth), typically asymmetrical in cross-profile, and are the product of hydrodynamic instability related to sand flux, the local topography, shear stress exerted by the wind on sand grains, and flow-form interactions induced by the topography of the dune itself. Wind ripples by comparison are small (amplitudes of 0.6 - 15 mm), are more symmetrical in pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
