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Ares Vallis

Ares Vallis

Ares Vallis is a valley on Mars which appears to have been carved by fluids, perhaps water. The valley 'flows' out of the hilly Margaritifer Terra and into the flat Chryse Planitia. Its name comes from the Greek name for Mars: Ares, the god of war. Ares Vallis was the landing site of NASA's Mars Pathfinder spacecraft, which studied a region of the valley near the border with Chryse in 1997. 1997

Valley

:This article is about the physical-geographic term. For places named "Valley" see Valley (disambiguation). Valley (disambiguation)-Iceland]] A valley is a landform, which can range from a few square miles (square kilometers) to hundreds or even thousands of square miles (square kilometers) in area. It is typically a low-lying area of land, surrounded by higher areas such as mountains or hills. Valleys are formed by numerous geographical processes. Glacial valleys, which are usually U- rather than V-shaped, were formed tens of thousands of years ago (most likely during the last Ice Age) by the massive erosive power of glaciers. Several glacial valleys can be found in the English Lake District and many can be found in Alpine countries. Rift valleys, such as the Great Rift Valley, are formed by the expansion of the Earth's crust due to tectonic activity beneath the Earth's surface. Valleys are, however, most commonly formed by fluvial activity (the action of running water, such as rivers), which erodes the landscape.

Hollows

A hollow is loose name for a valley in the earth. It is commonly used in New England to describe such geographic features. Hollows may be formed by river valleys such as Mansfield Hollow or they may be relatively dry clefts with a notch like characteristic in that they have a height of land and consequent water divide in their bases. A hollow such as this is Boston Hollow.

Famous valleys

- California Central Valley
- Copper Canyon
- Death Valley
- Grand Canyon
- Great Rift Valley
- Loire Valley
- Napa Valley
- Rhone Valley
- Shenandoah Valley
- Valley of the Kings
- San Fernando Valley
- Santa Clara Valley (Silicon Valley)

Extraterrestrial valleys

Planets and moons other than the Earth can also have valley-like features. Lunar valleys can be formed due to a linked chain of impact craters. Smaller valleys, known as rilles, can be formed due lava flows or because of contractions in cooling lava sheets. The Valles Marineris formation on Mars is a valley nearly 4000 km in length. It was originally formed by tectonic forces, but has been expanded by erosion.

Mars

Mars, the fourth planet from the Sun in our solar system, is named after the Roman god of war Mars (Ares in Greek mythology), because of its apparent red color. This feature also earned it the nickname "The Red Planet". Mars has two moons, Phobos and Deimos, which are small and oddly-shaped, possibly being captured asteroids. The prefix areo- refers to Mars in the same way geo- refers to Earth—for example, areology versus geology. (However, areology is also used to refer to the study of Mars as a whole rather than just the geological processes of the planet.) The astronomical symbol for Mars is a circle with an arrow pointing northeast (Unicode: ♂). This symbol is a stylized representation of the shield and spear of the god Mars, and in biology it is used as a sign for the male sex. The Chinese, Korean, Japanese, and Vietnamese cultures refer to the planet as the fire star, 火星, a naming based on the ancient Chinese mythological cycle of Five Elements.

Mythology

Mars has been obvious to skygazers since prehistoric times. It was known by the Egyptians as "Her Deschel" or "the Red One." Among the Babylonians Mars was known as "Nergal" or "the Star of Death." The Romans were the ones to give Mars its modern name, after their god of war.

Physical characteristics

The red, fiery appearance of Mars is caused by iron oxide (rust) on its surface. Mars has only a quarter the surface area of the Earth and only one-tenth the mass, though its surface area is approximately equal to that of the Earth's dry land because Mars lacks oceans. The solar day (or sol) on Mars is very close to Earth's day: 24 hours, 39 minutes, and 35.244 seconds.

Atmosphere

Mars' atmosphere is thin: the air pressure on the surface is only 750 pascals, about 0.75% of the average on Earth. However, the scale height of the atmosphere is about 11 km, somewhat higher than Earth's 6 km. The atmosphere on Mars is 95% carbon dioxide, 3% nitrogen, 1.6% argon, and contains traces of oxygen and water. The atmosphere quite dusty, giving the Martian sky a tawny color when seen from the surface; data from the Mars Exploration Rovers indicates the suspended dust particles are roughly 1.5 microns across. In 2003, methane was apparently discovered in the atmosphere by Earth-based telescopes and possibly confirmed in March 2004 by the Mars Express Orbiter; present measurements state an average methane concentration of about 11±4 ppb by volume (see reference). The thin atmosphere cannot hold heat and is the cause of the lower temperatures on Mars. The maximum temperature is roughly 20℃ (68℉). The presence of methane on Mars would be very intriguing, since as an unstable gas it indicates that there must be (or have been within the last few hundred years) a source of the gas on the planet. Volcanic activity, comet impacts, and the existence of life in the form of microorganisms such as methanogens are among possible but as yet unproven sources. The methane appears to occur in patches, which suggests that it is being rapidly broken down before it has time to become uniformly distributed in the atmosphere, and so it is presumably also continually being released to the atmosphere. Plans are now being made to look for other companion gases that may suggest which sources are most likely; in the Earth's oceans biological methane production tends to be accompanied by ethane, while volcanic methane is accompanied by sulfur dioxide. Other aspects of the Martian atmosphere vary significantly. In the winter months when the poles are in continual darkness, the surface gets so cold that as much as 25% of the entire atmosphere condenses out into meters thick slabs of CO₂ ice (dry ice). When the poles are again exposed to sunlight the CO₂ ice sublimates, creating enormous winds that sweep off the poles as fast as 250 mph. These seasonal actions transport large amounts of dust and water vapor giving rise to Earth-like frost and large cirrus clouds. These clouds of water-ice were photographed by the Opportunity rover in 2004.[http://marsrovers.jpl.nasa.gov/gallery/press/opportunity/20041213a/merb_sol290_clouds-B313R1_br.jpg] Recently, evidence has been discovered suggesting that Mars may be warming in the short term[http://news.bbc.co.uk/2/hi/science/nature/4266474.stm]; however, it is now cooler than it was in the 1970s.[http://catdynamics.blogspot.com/2005/09/climate-science-mars-and-politics.html]

Geology

Opportunity The surface of Mars is thought to be primarily composed of basalt, based upon the Martian meteorite collection and orbital observations. There is some evidence that some portion of the Martian surface might be more silica-rich than typical basalt, perhaps similar to andesitic rocks on Earth, though these observations may also be explained by silica glass. Much of the surface is deeply covered by dust as fine as talcum powder. Observations of the magnetic fields on Mars by the Mars Global Surveyor spacecraft have revealed that parts of the planet's crust has been magnetized. This magnetization has been compared to alternating bands found on the ocean floors of Earth. One interesting theory, published in 1999 and reexamined in October 2005 in a publication by the same group, is that these bands could be evidence of the past operation of plate tectonics on Mars. However, this has yet to be proven [http://photojournal.jpl.nasa.gov/catalog/PIA02008] or widely accepted and remains an area of active research. plate tectonics Amongst the findings from the Opportunity rover is the presence of hematite on Mars in the form of small spheres on the Meridiani Planum. The spheres are only a few millimeters in diameter and are believed to have formed as rock deposits under watery conditions billions of years ago. Other minerals have also been found containing forms of sulfur, iron or bromine such as jarosite. This and other evidence led a group of 50 scientists to conclude in the December 9, 2004 edition of the journal Science that "Liquid water was once intermittently present at the Martian surface at Meridiani, and at times it saturated the subsurface. Because liquid water is a key prerequisite for life, we infer conditions at Meridiani may have been habitable for some period of time in Martian history". On the opposite side of the planet the mineral goethite, which (unlike hematite) forms only in the presence of water, along with other evidence of water, has also been found by the Spirit rover in the "Columbia Hills". In 1996, researchers studying a meteorite (ALH84001) believed to have originated from Mars reported features which they attributed to microfossils left by life on Mars. As of 2005, this interpretation remains controversial with no consensus having emerged.
Topography
As of 2005 As of 2005 The dichotomy of Martian topography is striking: northern plains flattened by lava flows contrast with the southern highlands, pitted and cratered by ancient impacts. The surface of Mars as seen from Earth is consequently divided into two kinds of areas, with differing albedo. The paler plains covered with dust and sand rich in reddish iron oxides were once thought of as Martian 'continents' and given names like Arabia Terra (land of Arabia) or Amazonis Planitia (Amazonian plain). The dark features were thought to be seas, hence their names Mare Erythraeum, Mare Sirenum and Aurorae Sinus. The largest dark feature seen from Earth is Syrtis Major. Syrtis Major Mars has polar ice caps that contain frozen water and carbon dioxide that change with the Martian seasons — the carbon dioxide ice sublimates in summer it uncovers an underlying surface of layered water ice and dust. The polar carbon dioxide "hood" then forms again in winter. The supposedly-extinct shield volcano, Olympus Mons (Mount Olympus), is at 26 km the highest mountain in the solar system. It is in a vast upland region called Tharsis, which contains several large volcanos. See list of mountains on Mars. Mars also has the solar system's largest canyon system, Valles Marineris or the Mariner Valley, which is 4000 km long and 7 km deep. Mars is also scarred by a number of impact craters. The largest of these is the Hellas impact basin, covered with light red sand. See list of craters on Mars. The difference between Mars' highest and lowest points is nearly 31 km (from the top of Olympus Mons at an altitude of 26 km to the bottom of the Hellas impact basin at an altitude of 4 km below the datum). In comparison, the difference between Earth's highest and lowest points (Mount Everest and the Mariana Trench) is only 19.7 km. Combined with the planets' different radii, this means Mars is nearly three times "rougher" than Earth. The International Astronomical Union's Working Group for Planetary System Nomenclature is responsible for naming Martian surface features. Other notes: Zero elevation: Since Mars has no oceans and hence no 'sea level', a zero-elevation surface or mean gravity surface must be selected. The datum for Mars is defined by the fourth-degree and fourth-order spherical harmonic gravity field, with the zero altitude defined by the 610.5 Pa (6.105 mbar) atmospheric pressure surface (approximately 0.6% of Earth's) at a temperature of 273.16 K. This pressure and temperature correspond to the triple point of water. Zero meridian: Mars' equator is defined by its rotation, but the location of its Prime Meridian was specified, as was Earth's, by choice of an arbitrary point which was accepted by later observers. The German astronomers Wilhelm Beer and Johann Heinrich Mädler selected a small circular feature as a reference point when they produced the first systematic chart of Mars features in 1830-32. In 1877, their choice was adopted as the prime meridian by the Italian astronomer Giovanni Schiaparelli when he began work on his notable maps of Mars. After the spacecraft Mariner 9 provided extensive imagery of Mars in 1972, a small crater (later called Airy-0), located in the Sinus Meridiani ('Middle Bay' or 'Meridian Bay') along the line of Beer and Mädler, was chosen by Merton Davies of the RAND Corporation to provide a more precise definition of 0.0° longitude when he established a planetographic control point network. RAND Corporation
Canals
Mars has an important place in human imagination due to the belief by some that life existed on Mars. These beliefs are due mainly to observations by many in the 19th century popularized by Percival Lowell and Giovanni Schiaparelli. Schiaparelli called these observed features canali, meaning channels in Italian. This was popularly mistranslated as 'canals', and the myth of the Martian canals began. They were apparently artificial linear features on the surface that were asserted to be canals, and due to seasonal changes in the brightness of some areas that were thought to be caused by vegetation growth. This gave rise to many stories concerning Martians. The linear features are now known to be mostly non-existent or, in some cases, dry ancient watercourses. The color changes have been ascribed to dust storms.
Ice lakes
many stories On 29 July 2005, the BBC reported that a visible ice lake had been discovered in a crater in the north polar region of Mars[http://news.bbc.co.uk/1/hi/sci/tech/4727847.stm]. Images of the crater, taken by the High Resolution Stereo Camera on board the European Space Agency's Mars Express spacecraft, clearly show a broad sheet of ice in the bottom of an unnamed crater located on Vastitas Borealis, a broad plain that covers much of Mars' far northern latitudes, at approximately 70.5° North and 103° East. The crater is 35 km (23 mi) wide and about 2 km (1.2 mi) deep. The BBC report however, appears to have either intentionally sensationalized or unintentionally mis-interpreted the original HRSC/Mars Express feature[http://www.esa.int/SPECIALS/Mars_Express/SEMGKA808BE_0.html], which makes no claim or insinuation that this is a "lake". Like many thousands of other places on Mars, this ice sheet is a thin layer of frost that has condensed onto dark, cold sand dunes (about 200 m high) making their way across the bottom of the crater. The only thing remarkable about this feature is that it is far enough north to maintain at least some frost throughout the year.
The moons of Mars
Mars has two tiny natural moons, Phobos and Deimos, which orbit very close to the planet and are thought to be captured asteroids.
The exploration of Mars
asteroid Dozens of spacecraft, including orbiters, landers, and rovers, have been sent to Mars by the Soviet Union, the United States, Europe, and Japan to study the planet's surface, climate, and geography. Roughly two-thirds of all spacecraft destined for Mars have failed in one manner or another before completing or even beginning their missions. Part of this high failure rate can be ascribed to technical problems, but enough have either failed or lost communications for no apparent reason that some researchers half-jokingly speak of an Earth-Mars "Bermuda Triangle" or of a Great Galactic Ghoul which subsists on a diet of Mars probes, or of a Mars Curse. Among the most successful missions are the Mars probe program, the Mariner and Viking programs, Mars Global Surveyor, Mars Pathfinder, and Mars Odyssey. Global Surveyor has taken pictures of gullies and debris flow features that suggest there may be current sources of liquid water, similar to an aquifer, at or near the surface of the planet. Another possible origin proposed for these gully features is transient melting of surface water snow, frost, or ice. Mars Odyssey determined that there are significant deposits of water ice in the upper meter or so of Mars' regolith within 30° of the north and south pole. In 2003, the ESA launched the Mars Express craft consisting of the Mars Express Orbiter and the lander Beagle 2. Attempts to contact the Beagle 2 failed and it was declared lost in early February 2004. Beagle 2 Also in 2003, NASA launched the twin Mars Exploration Rovers named Spirit (MER-A) and Opportunity (MER-B). Both missions landed successfully in January 2004 and have met or exceeded all their targets; while a 90-day nominal mission was planned, as of February 2005, their missions have been extended twice and they continue to return science, although some mechanical faults have occurred. Among the most significant science return has been evidence of liquid water some time in the past at both landing sites. In addition, dust devils imaged from ground-level have been detected moving across the surface of Mars by Spirit (MER-A). (See picture below). Dust devils were first imaged on Mars from the surface by Mars Pathfinder. Mars Pathfinder
Nomenclature

Early nomenclature
Although better remembered for mapping the Moon starting in 1830, Johann Heinrich Mädler and Wilhelm Beer were the first "areographers". They started off by establishing once and for all that most of the surface features were permanent, and pinned down Mars' rotation period. In 1840, Mädler combined ten years of observations and drew the first map of Mars ever made. Rather than giving names to the various markings they mapped, Beer and Mädler simply designated them with letters; Meridian Bay (Sinus Meridiani) was thus feature "a". Over the next twenty years or so, as instruments improved and the number of observers also increased, various Martian features acquired a hodge-podge of names. To give a couple of examples, Solis Lacus was known as the "Oculus" (the Eye), and Syrtis Major was usually known as the "Hourglass Sea" or the "Scorpion". In 1858, it was also dubbed the "Atlantic Canale" by the Jesuit astronomer Angelo Secchi. Secchi commented that it "seems to play the role of the Atlantic which, on Earth, separates the Old Continent from the New" —this was the first time the fateful canale, which in Italian can mean either "channel" or "canal", had been applied to Mars. In 1867, Richard Anthony Proctor drew up a map of Mars based, somewhat crudely, on the Rev. William Rutter Dawes' earlier drawings of 1865, then the best ones available. Proctor explained his system of nomenclature by saying, "I have applied to the different features the names of those observers who have studied the physical peculiarities presented by Mars." Here are some of his names, paired with those later proposed by Schiaparelli:
- Kaiser Sea = Syrtis Major1865
- Lockyer Land = Hellas
- Main Sea = Lacus Moeris
- Herschel II Strait = Sinus Sabaeus
- Dawes Continent = Aeria and Arabia
- De La Rue Ocean = Mare Erythraeum
- Lockyer Sea = Solis Lacus
- Dawes Sea = Tithonius Lacus
- Madler Continent = Chryse, Ophir, Tharsis
- Maraldi Sea = Mares Sirenum and Cimmerium
- Secchi Continent = Memnonia
- Hooke Sea = Mare Tyrrhenum
- Cassini Land = Ausonia
- Herschel I Continent = Zephyria, Aeolis, Aethiopis
- Hind Land = Libya Proctor's nomenclature has often been criticized, mainly because so many of his names honored English astronomers, but also because he used many names more than once. In particular, Dawes appeared no fewer than six times (Dawes Ocean, Dawes Continent, Dawes Sea, Dawes Strait, Dawes Isle, and Dawes Forked Bay). Even so, Proctor's names are not without charm, and for all their shortcomings they were a foundation on which later astronomers would improve.
Modern nomenclature
Today, features on Mars derive from a number of sources. Large albedo features retain many of the older names, but are often updated to reflect new knowledge of the nature of the features. For example 'Nix Olympica' (the snows of Olympus) has become 'Olympus Mons' (Mount Olympus). Large Martian craters are named after important scientists and science fiction writers; smaller ones are named after towns and villages on Earth.
Observation of Mars
Earth passes Mars every 780 days (or two years plus seven weeks and one day) at a distance of about 80,000,000 km. However, this varies because the orbits are elliptical. To a naked-eye observer, Mars usually shows a distinct yellow, orange or reddish colour, and varies in brightness more than any other planet as seen from Earth over the course of its orbit, due to the fact that when furthest away from the Earth it is more than seven times as far from the latter as when it is closest (and can be lost in the Sun's glare for months at a time when least favourably positioned). At its most favourable times — which occur twice every 32 years, alternately at 15 and 17-year intervals, and always between late July and late September — Mars shows a wealth of surface detail to a telescope. Especially noticeable, even at low magnification, are the polar ice caps. polar ice cap On August 27, 2003, at 9:51:13 UT, Mars made its closest approach to Earth in nearly 60,000 years: 55,758,006 km (approximately 35 million miles) without Light-time correction. This close approach came about because Mars was one day from opposition and about three days from its perihelion, making Mars particularly easy to see from Earth. The last time it came so close is estimated to have been on September 12, 57,617 BC. Detailed analysis of the solar system's gravitational landscape forecasts an even closer approach in 2287. However, to keep this in perspective, this record approach was only an imperceptibly tiny fraction less than other recent close approaches that occur four times every 284 years. For instance, the minimum distance on August 22 1924 was 0.37284 AU, compared to 0.37271 AU on August 27 2003, and the minimum distance on August 24 2208 will be 0.37278 AU. A transit of the Earth as seen from Mars will occur on November 10, 2084. At that time the Sun, the Earth and Mars will be exactly in a line. There are also transits of Mercury and transits of Venus, and the moon Deimos is of sufficiently small angular diameter that its partial "eclipses" of the Sun are best considered transits (see Transit of Deimos from Mars). The only occultation of Mars by Venus to be observed was that of October 3, 1590, seen by M. Möstlin at Heidelberg. Heidelberg
Appearance

Martian meteorites
:Main article: Martian meteorites A handful of objects are known that are surely meteorites and may be of Martian origin. Two of them may show signs of ancient bacterial activity. On August 6, 1996 NASA announced that analysis of the ALH 84001 meteorite thought to have come from Mars, shows some features that may be fossils of single-celled organisms, although this idea is controversial. In Solar System Research (March 2004, vol 38, page 97) it was suggested that the unique Kaidun meteorite, recovered from Yemen, may have originated on the Martian moon of Phobos. On April 14, 2004, NASA revealed that a rock known as "Bounce", studied by the Mars Exploration Rover Opportunity, was similar in composition to the meteorite EETA79001-B, discovered in Antarctica in 1979. The rock may have been ejected from the same crater as the meteorite, or from another crater in the same area of the Martian surface.
Life on Mars
Evidence exists that the planet once was significantly more habitable than today, but the question whether living organisms ever actually existed there is an open one. Some researchers think that a certain rock which is believed to have originated on Mars - specifically, meteorite ALH84001 - does contain evidence of past biologic activity, but no consensus about these claims has been achieved so far and recent research indicates that the rock, since its creation several billion years ago, has never been exposed to temperatures for extended periods of time that would allow for liquid water. The Viking probes carried experiments designed to detect microorganisms in Martian soil at their respective landing sites, and had some positive results, later denied by many scientists, resulting in ongoing controversy. Also, present biologic activity is one of the explanations that have been suggested for the presence of traces of methane within the Martian atmosphere, but other explanations not involving life are generally considered more likely. If colonization is going to happen, Mars seems a likely choice due to its rather hospitable conditions (compared with other planets, it is most like Earth).
The Mars flag
colonization In early 2000, a proposed Mars flag flew aboard the space shuttle Discovery. Designed by NASA engineer and Flashline Mars Arctic Research Station task force leader Pascal Lee and carried aboard by astronaut John Mace Grunsfeld, the flag consists of three vertical bars (red, green, and blue), symbolizing the transformation of Mars from a barren planet (red) to one bearing sustainable life (green), and finally to a fully terraformed planet with open bodies of water. This design was suggested by the Kim Stanley Robinson sci-fi trilogy Red Mars, Green Mars, and Blue Mars. While other designs have been proposed, the republican tricolor has been adopted by the Mars Society as its own official banner. In a statement released after the launch of the mission, the Society said that the flag "has now been honored by a vessel of the leading spacefaring nation on Earth," and added that "(i)t is fitting that this action occurred when it did: at the dawning of a new millenium."
Mars in fiction
The depiction of Mars in fiction has been stimulated its dramatic red color and by early scientific speculations that its surface conditions might be capable of supporting life. Until the arrival of planetary probes, the traditional view of Mars derived from the astronomers Percival Lowell and Giovanni Schiaparelli, whose observation of supposedly linear features on the planet created the myth of canals on Mars. For many years, a standard notion of the planet as a drying, cooling, dying world with ancient civilizations constructing irrigation works. Thus originated a large number of science fiction scenarios, the best known of which is H. G. Wells' The War of the Worlds, in which Martians seek to escape their dying planet by invading Earth. After the Mariner and Viking spacecraft had returned pictures of Mars as it really is, an apparently lifeless and canal-less world, these ideas about Mars had to be abandoned and a vogue for accurate, realist depictions of human colonies on Mars developed, the best known of which may be Kim Stanley Robinson's Mars trilogy. However, pseudo-scientific speculations about the Face on Mars and other enigmatic landmarks spotted by space probes have meant that ancient civilizations continue to be a popular theme in science fiction, especially in film. Another popular theme, particularly among American writers, is the Martian colony that fights for independence from Earth. This is a major plot element in the novels of Greg Bear and Kim Stanley Robinson, as well as the movie Total Recall (based on a novel by Philip K. Dick) and the television series Babylon 5. Many video games also use this element, such as Red Faction.
See also

- Areography
- Astrobiology
- Astronomy on Mars
- Colonization of Mars
- Darian calendar
- Face on Mars photo article
- Timekeeping on Mars
- Exploration of Mars
- List of artificial objects on Mars
- List of craters on Mars
- List of mountains on Mars
- Martian meteorite
- Mars photos
- Mars in fiction
- Extraterrestrial life
- Terraforming
- Mars Direct
- Mars in astrology
- Ares
- Tyr
- Richard C. Hoagland
References

- William Sheehan, [http://www.uapress.arizona.edu/onlinebks/mars/contents.htm The Planet Mars: A History of Observation and Discovery], The University of Arizona Press, Tucson, 1996
- Vladimir A. Krasnopolsky, Jean-Pierre Maillard, Tobias C. Owen, [http://www.google.ca/url?sa=U&start=1&q=http://www.cosis.net/abstracts/EGU04/06169/EGU04-A-06169.pdf&e=912 Detection of methane in the Martian atmosphere: evidence for life?], Icarus, 172 (2), 537-547. [http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2004Sci...306.1753L&db_key=AST&data_type=HTML&format=&high=439c7b95b425777 Lemmon et al., "Atmospheric Imaging Results from the Mars Exploration Rovers: Spirit and Opportunity"]
External links

- [http://nssdc.gsfc.nasa.gov/planetary/factsheet/marsfact.html NASA's Mars fact sheet]
- [http://www.nineplanets.org/mars.html Nine Planets Mars page]
- [http://www.marsnews.com MarsNews.com - News and info site]
- [http://www.student.oulu.fi/~jkorteni/space/mars/surface/ Introduction to Martian topography, with Hubble Space Telescope photos]
- [http://www.geoinf.fu-berlin.de/mex/ FU Berlin: HRSC (camera) experiment at Mars Express] (eng. & ger.; press releases and high resolution images)
- [http://www.giss.nasa.gov/tools/mars24/help/notes.html Technical Notes about Time on Mars]
- [http://history.nasa.gov/SP-4212/on-mars.html On Mars: Exploration of the Red Planet 1958-1978] from the NASA History Office.
- [http://flagspot.net/flags/mars.html The Mars Society flag]
- [http://www.vias.org/spacetrip/mars_globalview.html A Trip Into Space] Photos and descriptions of Mars
- [http://www.cato.org/pubs/wtpapers/980815paper.html Martian Law - a CATO white paper]
- [http://www.marsunearthed.com/ Mars Unearthed] - Comparisons of terrains between Earth and Mars
- [http://www.ibiblio.org//e-notes/VRML/Globe/Globe.htm 3D VRML Mars globe]
- [http://www.enterprisemission.com/ Enterprise Mission: Richard C. Hoagland's Homepage]
Water on Mars

- [http://news.bbc.co.uk/1/hi/sci/tech/4727847.stm Highly visible ice lake found on Mars - BBC]
- Dr. Tony Phillips: [http://science.nasa.gov/headlines/y2000/ast29jun_1m.htm "Making a Splash on Mars"], Science@NASA article, June 29, 2000. Phillips describes the Martian "gullies" and explains the conditions under which liquid water can exist on the surface of Mars.
- [http://news.bbc.co.uk/hi/english/sci/tech/newsid_2009000/2009318.stm BBC News story on subsurface ice deposits on Mars]
- [http://news.bbc.co.uk/1/hi/sci/tech/3426539.stm BBC News update on Mars Express' findings of polar water ice and water-eroded features on the surface]
- [http://www.nasa.gov/vision/universe/solarsystem/opportunity_water.html Mars Rover Scientists Wring Water Story from Rocks] This image taken by Mars Rover Opportunity shows microscopic rock forms indicating past signs of water. Courtesy: NASA
- [http://news.bbc.co.uk/1/hi/sci/tech/4285119.stm BBC News Mars pictures reveal frozen sea]
Mars exploration

- [http://www.transhumanist.com/volume4/space.htm The Political Economy of Very Large Space Projects (Journal Of Evolution and Technology)]
- [http://www.exploremarsnow.org/ exploreMarsnow] Interactive Mars base simulation. Winner of 2003 Webby Award for Science.
- [http://marsrovers.jpl.nasa.gov/home/index.html NASA Mars Exploration Rover Home Page]
- [http://dualmoments.com/marsrovers/index.html Be on Mars] Anaglyphs from the Mars Rovers (3D)
- als:Mars (Planet) ko:화성 ms:Marikh ja:火星 simple:Mars (planet) th:ดาวอังคาร

Ancient Greek

Ancient Greek refers to the stage in the history of the Greek language corresponding to Classical Antiquity, which normally applies to two periods of Greek history: Archaic and Classical Greece. The Ancient era of Greek history normally includes also the Hellenistic (post-Classic) age; however, that period formally composes its own stage in the Greek Language known as Hellenistic Greek. For information on the Greek language prior to the creation of the Greek alphabet, see articles Mycenaean Greek and Proto-Greek.

Dialects of Ancient Greek

The Greek language had started shaping in local forms even before the settling of the Greek-speaking tribes into Greece, yet the actual dialectic variation took place afterwards. Throughout history the Greek language is presented in a number of dialects that did not apply on fixed geographical borders, and even if it did, those borders would be constantly altered because of the frequent migrations of the Hellenic peoples. According to its linguistic variations, the Ancient Greek language of the Archaic and Classic periods is composed by the following symbolic dialectic branches: The dialects of the pre-classical and classical period appear documented in writing beginning in the 8th century BC, and they certainly developed well before this date. The most standard formulation currently for the pre-classical and classical dialects is four or five major groups: # Northwest Greek (including Doric, and possibly Ancient Macedonian) # Aeolic (including Boeotian, Lesbian, Thessalian, and Aegean/Asiatic Aeolic subdivisions) # Attic-Ionic # Arcado-Cyprian # and possibly Pamphylian As each of the above dialectic branches is broken down to its individual dialects, each dialect can in turn be divided into countless local idioms. The information provided in the dialect-specific articles is a general linguistic description that is confined to the main characteristics of the Common form (Koine) of each dialect, without getting into detail about their numerous idiomatic variations. In that respect, the article on Doric describes the "Common" form of Doric as it is seen, e.g., in Pindar's poetry, which differs from local forms such as Laconian, Cretan, Sicilian or even Theban Doric. The Arcado-Cyprian group appears to be closest to Mycenaean Greek, and is likely its direct descendant. Northwest/Doric is the most distinct from the others. Controversy on the early history of Greek dialects generally focuses on the nature of Aeolic and Attic-Ionic—with various configurations of independent development or relations to Mycenaean or Northwest/Doric proposed. The relations between the dialects are likely obscured by significant amounts of influence on each other. After the conquests of Alexander the Great in the 4th century BC, a new international dialect known as Koine or Common Greek developed, largely based on Attic Greek, but with influence from other dialects. This dialect slowly replaced most of the older dialects, although Doric dialect has survived to the present in the form of the Tsakonian and Southern Italian dialect of Modern Greek. Doric has also passed down its Aorist terminations into most verbs of Demotic Greek. By about the 7th century AD., the Koine had slowly metamorphosized into Medieval Greek.

Sound changes

These sound changes since Proto-Greek affect most or all Ancient Greek dialects:
- Syllabic /r/, /l/ become /ro/ and /lo/ in Mycenean Greek and Aeolic Greek; otherwise /ra/ and /la/, but /ar/ and /al/ before resonants and analogously.
- Loss of /h/ from original /s/ (except initially) and of /j/.
- Loss of /w/ in many dialects (later than loss of /h/ and /j/).
- Loss of labiovelars, which were converted (mostly) into labials, sometimes into dentals or velars.
- Contraction of adjacent vowels resulting from loss of /h/ and /j/ (and, to a lesser extent, from loss of /w/); more in Attic Greek than elsewhere.
- Rise of a distinctive circumflex accent, resulting from contraction and certain other changes.
- Limitation of the accent to the last three syllables, with various further restrictions.
- Loss of /n/ before /s/ (incompletely in Cretan Greek), with compensatory lengthening of the preceding vowel. Note that /w/ and /j/, when following a vowel and not preceding a vowel, combined early on with the vowel to form a diphthong and were thus not lost. The loss of /h/ and /w/ after a consonant were often accompanied by compensatory lengthening of a preceding vowel. The loss of /j/ after a consonant was accompanied by a large number of complex changes, including diphthongization of a preceding vowel or palatalization or other change to a directly preceding consonant. Some examples:
- /pj/, /bj/, /phj/ -> /pt/
- /lj/ -> /ll/
- /tj/, /thj/, /kj/, /khj/ -> /s/ when following a consonant; otherwise /tt/ (Attic), /ss/ (Ionic)
- /gj/, /dj/ -> /zd/
- /mj/, /nj/, /rj/ -> /j/ is transposed before consonant and forms a diphthong with the preceding vowel
- /wj/, /sj/ -> /j/, forming a diphthong with the preceding vowel The results of vowel contraction were complex and differed from dialect to dialect. Such contractions occur in the inflection of a number of different noun and verb classes and are among the most difficult aspects of Ancient Greek grammar. They were particularly important in the large class of contracted verbs, denominative verbs formed from nouns and adjectives ending in a vowel. (In fact, the reflex of contracted verbs in Modern Greek—i.e., the set of verbs derived from Ancient Greek contracted verbs—represents one of the two main classes of verbs in that language.)

Sounds

The pronunciation of Post-Classic Greek changed considerably from Ancient Greek, although the orthography still reflects features of the older language (see W. Sidney Allen, Vox Graeca – a guide to the pronunciation of Classical Greek). For a detailed description on the phonology changes from Ancient to Hellenistic periods of the Greek language, see the article on Koine Greek. The examples below are intended to represent Attic Greek in the 5th century BC. Although ancient pronunciation can never be reconstructed with certainty, Greek in particular is very well documented from this period, and there is little disagreement among linguists as to the general nature of the sounds that the letters represented.

Vowels

Short vowels

The short e (ε in Greek orthography) is shown in the table as mid close vowel , but it may have been nearer to .

	Front	Back
Close unrounded
Close rounded
Close-mid
Open

Long Vowels

The [] (ου in Greek orthography) probably changed to [] by the fourth century.

	Front	Back
Close unrounded
Close rounded
Close-mid
Open-mid
Open

Consonants

Note: [z] was an allophone of [s], used before voiced consonants, and in particular in the combination [zd] written as zeta (ζ). The [] (voiceless r) written as rho with a rough breathing () was probably an allophone of [r].

Consonant classes

There are three main classes of consonants:
- Stops. This include three subclasses: velars (k, g, kh), labials (p, b, ph), and dentals (t, d, th).
- Sonorants are m, n, l, r.
- Fricatives are s and h.

Consonant contractions

In verb conjugation, one consonant often comes up against the other. Various sandhi rules apply. Rules:
- Most basic rule: When two sounds appear next to each other, the first assimilates in voicing and aspiration to the second.
- This applies fully to stops. Fricatives assimilate only in voicing, sonorants do not assimilate.
- Before an s (future, aorist stem), velars become k, labials p, and dentals disappear.
- Before a th (aorist passive stem), velars become kh, labials ph, dentals s.
- Before an m (perfect middle first-singular, first-plural, participle), velars become g, nasal+velar becomes g, labials m, dentals and n become s, other sonants remain.

Compensatory lengthening

There are different schemes for compensatory lengthening, depending on where it happens. The differences are in whether a becomes ā or ē, and whether e and o become the closed values ei /eː/ and ou /oː/ or the open values ē /ɛː/ and ō /ɔː/.

Augment

The indicative of past tenses adds (conceptually, at least) a prefix /e-/. This was probably originally a separate word, meaning something like "then", added because tenses in PIE had primarily aspectual meaning. The augment is added to the indicative of the aorist, imperfect and pluperfect, but not to any of the other forms of the aorist (no other forms of the imperfect and pluperfect exist). There are two kinds of augment in Greek, syllabic and quantitative. The syllabic augment is added to stems beginning with consonants, and simply prefixes e (stems beginning with r, however, add er). The quantitative augment is added to stems beginning with vowels, and involves lengthening the vowel:
- a, ā, e, ē -> ē
- i, ī -> ī
- o, ō -> ō
- u, ū -> ū
- ai -> ēi
- ei -> ēi or ei
- oi -> ōi
- au -> ēu or au
- eu -> ēu or eu
- ou -> ou Some verbs augment irregularly; the most common variation is e -> ei. The irregularity can be explained diachronically by the loss of s between vowels. The augment is sometimes omitted in poetry (Epic Greek). The augment sometimes substitutes for reduplication; see below.

Reduplication

All forms of the perfect, pluperfect and future perfect reduplicate the initial syllable of the verb stem. There are three types of reduplication:
- Syllabic reduplication: Most verbs beginning with a single consonant, or a cluster of a stop with a sonorant, add a syllable consisting of the initial consonant followed by e. An aspirated consonant, however, reduplicates in its unaspirated equivalent: this is often referred to as Grassman's Law.
- Augment: Verbs beginning with a vowel, as well as those beginning with a cluster other than those indicated previously (and occasionally for a few other verbs) reduplicate in the same fashion as the augment. Note that this remains in all forms of the perfect, not just the indicative.
- Attic reduplication: Some verbs beginning with an a, e or o, followed by a sonorant (or occasionally d or g), reduplicate by adding a syllable consisting of the initial vowel and following consonant, and lengthening the following vowel. Hence er -> erēr, an -> anēn, ol -> olōl, ed -> edēd. This is not actually specific to Attic Greek, despite its name. This originally involved reduplicating a cluster consisting of a laryngeal and sonorant; hence h₃l -> h₃leh₃l -> olōl with normal Greek development of laryngeals. (Forms with a stop were analogous.) Irregular duplication can be understood diachronically. For example, lambanō (root lab) has the perfect stem eilēpha (not
- lelēpha) because it was originally slambanō, with perfect seslēpha, becoming eilēpha through (semi-)regular change.

Grammatical forms

Ancient Greek, like all of the older Indo-European languages, is highly inflected. Ancient Greek is highly archaic in its preservation of Proto-Indo-European forms. Nouns (including proper nouns) have five cases (nominative, genitive, dative, accusative and vocative), three genders (masculine, feminine and neuter), and three numbers (singular, dual and plural). Verbs have four moods (indicative, imperative, subjunctive and optative), three voices (active, middle and passive), as well as three persons (first, second and third) and various other forms. Verbs are conjugated in four main tenses (present, aorist, perfect, and future), with a full complement of moods for each main tense, although there is no future subjunctive or imperative. (The distinction of the "tenses" in moods other than the indicative is actually mostly of aspect.) In addition, indicative forms of the imperfect and pluperfect exist. Infinitives and participles for all corresponding finite combinations of tense and voice, excluding the imperfect and pluperfect.

Nouns

Ancient Greek nouns have three numbers (singular, dual, and plural), three genders (masculine, feminine, and neuter) and five cases (nominative, genitive, dative, accusative and vocative). The two major noun declensions are the vowel declension and the consonant declension. The vowel declension is split into the alpha-declension and the omicron-declension. There is also the minor consonant declension.

Alpha Declension

The alpha declension is predominantly, but not exclusively, feminine. Nouns belonging to the alpha declension have stems ending in alpha, short or long. In certain circumstances the alpha may change its length or become eta. In the table below of feminine nouns there are three examples: long-alpha stem (-stems), short-alpha stems (-stems), and a stems which can end in eta (-stems).

Ares

This article is about Ares, the Greek god of war. For other possible meanings of the name Ares, see Ares (disambiguation). Ares (disambiguation) In Greek mythology, Ares ("battle strife"; in Greek, Ἄρης), is the god of war and before battle people worshipped him. The Romans identified Mars, the god of war that they inherited from the Etruscans, with Hellenic Ares, but maintained a different, less ambiguous relation with him. Among the Hellenes, Ares was always mistrusted: his birthplace and true home was placed afar off, among the barbarous and warlike Thracians (Iliad xiii.301; Odyssey viii.361; Ovid). Although important in poetry, Ares was only rarely the recipient of cult worship, save at Sparta and in the founding myth of Thebes, and he appeared in few myths (Burkert 1985, p.169). The temple to Ares in the agora of Athens that Pausanias saw in the 2nd century CE had only been moved and rededicated there during the time of Augustus; in essence it was a Roman temple to Mars. The single major role of Ares sited in mainland Greece itself was in the founding myth of Thebes: Ares was the progenitor of the water-dragon slain by Cadmus. From the dragon's teeth sown as if a crop, arose a race of fighting men, the descendents of Ares. To propitiate Ares, Cadmus took as a bride Harmonia, daughter of Ares' union with Aphrodite, thus harmonizing all strife and founding the city of Thebes. Among the so-called "Homeric hymns", a "Hymn to Ares" has been transmitted in the manuscripts, although modern scholarship has detected that it was written in Late Antiquity (Burkert p 415, note 15). Even so, apart from sacrifices to him made by commanders of armies in the field, Ares was venerated most often in conjunction with other gods; for example, he shared a temple with Aphrodite at Thebes. Besides Aphrodite, the adjective areios, areia is applied to other gods in their warlike aspect. In the Iliad "Ares" is as often embodied in a battle formula connoting rough strife as he is personified as a bronze-armoured god: he is repeatedly contrasted with Athena, to his disadvantage. To Athena is reserved the one glorious aspect of war, Nike, "victory". (Burkert p 169). At Athens, the Areios pagus near the Acropolis, is equally the "Hill of Ares" and simply the "Battle Hill". For Mars, Enyalios was sometimes used as an epithet: see Ares Enyalius. Interestingly, the Mycenean Greek Linear B tablets list a god Enyalios, while ares seems already to be a common noun meaning "war." By classical times, however, Enyalios had been demoted to the status of hero (as in the Iliad) and Ares the name for the god. Enyalios survived as a cult-title in only a few settings, most notably in the oath of the ephebes at Athens. In one archaic mytheme, related by the ancient earth-goddess Dione to her daughter Aphrodite, two chthonic giants, the brothers Otus and Ephialtes, threw Ares into chains and put him in a bronze urn, where he had to endure for thirteen months, a lunar year. "And that would have been the end of Ares and his appetite for war, if the beautiful Eriboea, the young giants' stepmother, had not told Hermes what they had done," she related (Illiad, v. 385–91). "In this one suspects a festival of licence which is unleashed in the thirteenth month," Burkert observes (p 169). Hermes is at his feet. (Museo delle Termi, Rome)]] There are accounts of a son of Ares, Cycnus (Kyknos) of Macedonia, who was so murderous that he attempted to build a temple with the skulls and the bones of travellers. Heracles slaughtered this abominable monstrosity, engendering the wrath of Ares, whom the hero wounded (Apollodorus 2.114). Ares gave Hippolyte the girdle that Heracles took. In an episode sung in the hall of Alcinous, king of the Phaeacians (Odyssey viii.302ff), Ares lay in bed with Aphrodite, wife of Hephaestus, and Helios the Sun spied the love-making couple, alerting Hephaestus, who was angered. Hephaestus rigged the bed with invisibly fine net of chain with the power to hold anything in place, including gods, and caught Ares and Aphrodite on the next occasion. He brought the other gods to witness the adultery—the goddesses stayed away out of modesty—thinking to humiliate Ares and Aphrodite, but the gods all laughed. Poseidon agreed to refund to cuckolded Hephaestus the bride-price of Aphrodite. Once the couple were loosed, Ares sped away to his homeland, Thrace. (In a much later interpolated detail, Ares put a youth Alectryon by his door to guard them, but Alectryon fell asleep. Ares turned Alectryon into a rooster, which never forgets to announce the arrival of the sun in the morning.) In the Trojan War, Ares had no fixed allegiances nor respect for Themis, the right ordering of things: he promised Athena and Hera that he would fight on the side of the Achaeans, but Aphrodite was able to persuade Ares to side with the Trojans. During the war, Diomedes fought with Hector and saw Ares fighting on the Trojans' side. Diomedes called for his soldiers to fall back slowly. Hera, Ares's mother, saw his interference and asked Zeus, his father, for permission to drive Ares away from the battlefield. Hera encouraged Diomedes to attack Ares, so he threw a spear at Ares. Athena then drove the spear into Ares's body, who bellowed in pain and fled to Mt. Olympus, forcing the Trojans to fall back. In post-Renaissance emblem books, Ares's symbols are a spear and a helmet, his animal the dog and his bird the vulture. In myth and poetry Ares appears as cruel, aggressive, and blood-thirsty. He is notorious with both gods and humans.

Consorts/Children

# Aglaulus ## Alcippe # Aphrodite ## Anteros ## Deimos (Dread) ## Eros (Love) ## Harmonia ## Himerus ## Phobos (Fright) # Astyoche ## Ascalaphus # Atalanta ## Parthenopeus # Chryse ## Phlegyas # Cyrene ## Diomedes # Otrera ## Hippolyte ## Penthesilea # Rhea Silvia ## Remus ## Romulus # Sterope ## Oenomaus # Pyrene ## Cycnus # Unknown mother ## Antiope ## Biston ## Enyo ## Eurytion ## Tereus # Unknown woman ## Antiope ## Hippolyte ## Melanippe

Ares in Neopaganism

Many modern Neopagans maintain a somewhat traditional view of Ares. Far from the glory that the Romans attributed to him however, most modern Neopagan sects, particularly Hellenistic sects in the United States, discourage worship of Ares altogether. Many sects even forbid Ares worship. Ares is often seen as a cruel, malevolent god who relishes in mortal suffering and feeds on strife. Many modern neopagans believe that ancient civilizations believed much the same, but worshipped Ares out of necessity rather than out of devotion. It is believed that Ares inspires feelings of malevolence and invincibility, sometimes coupled with delusions of grandeur, fueling acts of cruelty and strife. Acts of senseless violence, particularly absent of recognizable motive, are sometimes attributed to the influence of Ares. Some neopagans today do worship Ares, though sects that worship him are considered out of the mainstream and even called cults by Neopagan standards. It is commonly believed that Ares can grant his followers boons of unnatural strength and physical stamina, but that he always exacts a price on the spirit. Though worship of Ares is exceedingly rare, it can exist in many forms. The most common form of worship is in the form of animal sacrifices, particularly the sacrifice of goats which has been documented by police authorities. Most neopagans actively discouraged animal sacrifice, and most consider it cruel and inhumane. There are also laws against animal sacrifice in the United States and Canada.

External link

- [http://www.angelfire.com/empire/martiana/ares/index.html Ares in Greek Religion]

References

- Burkert, Walter, 1985. Greek Religion (Cambridge: Harvard University Press)
- Kerenyi, Carl, 1951. Gods of the Greeks (London:Thames & Hudson) Category:Greek gods Category:War gods ko:아레스 ja:アレス

NASA

] The National Aeronautics and Space Administration (NASA), which was established in 1958, is the agency responsible for the public space program of the United States of America. It is also responsible for long-term civilian and military aerospace research.

Vision and mission

NASA's vision is "to improve life here, extend life to there, and to find life beyond." Its mission is "to understand and protect our home planet; to explore the Universe and search for life; and to inspire the next generation of explorers."

History

Space Race

:For additional background, please see the Space Race article Space Race launch of Redstone rocket and NASA's Mercury 3 capsule Freedom 7 with Alan Shepard Jr. on the United States' first human flight into sub-orbital space. (Atlas rockets were used to launch Mercury's orbital missions.)]] Following the Soviet space program's launch of the world's first man-made satellite (Sputnik 1) on October 4, 1957, the attention of the United States turned toward its own fledgling space efforts. The U.S. Congress, alarmed by the perceived threat to U.S. security and technological leadership, urged immediate and swift action; President Dwight D. Eisenhower and his advisers counseled more deliberate measures. Several months of debate produced agreement that a new federal agency was needed to conduct all nonmilitary activity in space. On July 29, 1958, President Eisenhower signed the National Aeronautics and Space Act of 1958 establishing the National Aeronautics and Space Administration (NASA). When it began operations on October 1, 1958, NASA consisted mainly of the four laboratories and some 8,000 employees of the government's 46-year-old research agency for aeronautics, the National Advisory Committee for Aeronautics (NACA), though the probably most important contribution actually had its roots in the German rocket program led by Wernher von Braun, who is today regarded as the father of the United States space program. NASA's early programs were research into human spaceflight, and were conducted under the pressure of the competition between the USA and the USSR (the Space Race) that existed during the Cold War. The Mercury program, initiated in 1958, started NASA down the path of human space exploration with missions designed to discover simply if man could survive in space. Representatives from the U.S. Army (M.L. Raines, LTC, USA), Navy (P.L. Havenstein, CDR, USN) and Air Force (K.G. Lindell, COL, USAF) were selected/requested to provide assistance to the NASA Space Task Group through coordination with the existing U.S. military research and defense contracting infrastructure, and technical assistance resulting from experimental aircraft (and the associated military test pilot pool) development in the 1950s. On May 5, 1961, astronaut Alan B. Shepard Jr. became the first American in space when he piloted Freedom 7 on a 15-minute suborbital flight. John Glenn became the first American to orbit the Earth on February 20, 1962 during the 5-hour flight of Friendship 7. Once the Mercury project proved that human spaceflight was possible, project Gemini was launched to conduct experiments and work out issues relating to a moon mission. The first Gemini flight with astronauts on board, Gemini III, was flown by Virgil "Gus" Grissom and John W. Young on March 23, 1965. Nine other missions followed, showing that long-duration human space flight was possible, proving that rendezvous and docking with another vehicle in space was possible, and gathering medical data on the effects of weightlessness on humans.

Apollo program

Following the success of the Mercury and Gemini programs, the Apollo program was launched to try to do interesting work in space and possibly put men around (but not on) the Moon. The direction of the Apollo program was radically altered following President John F. Kennedy's announcement on May 25, 1961 that the United States should commit itself to "landing a man on the Moon and returning him safely to the Earth" by 1970. Thus Apollo became a program to land men on the Moon. The Gemini program was started shortly thereafter to provide an interim spacecraft to prove techniques needed for the now much more complicated Apollo missions. Gemini program.]] After eight years of preliminary missions, including NASA's first loss of astronauts with the Apollo 1 launch pad fire, and the first spacecraft to orbit the Moon (Apollo 8) at the end of 1968, the Apollo program achieved its goals with Apollo 11 which landed Neil Armstrong and Buzz Aldrin on the moon's surface on July 20, 1969 and returned them to Earth safely on July 24. Armstrong's first words upon stepping out of the Eagle lander captured the momentousness of the occasion: "That's one small step for [a] man, one giant leap for mankind." Twelve men would set foot on the Moon by the end of the Apollo program in December 1972. NASA had won the moon race, and in some senses this left it without direction, or at the very least without the public attention and interest that was necessary to guarantee large budgets from Congress. After President Lyndon Johnson left office, NASA lost its main political supporter, and rocket scientist Wernher von Braun was moved to a position lobbying in Washington. Plans for ambitious follow-on projects to construct a space station, establish a lunar base and launch a human mission to Mars by 1990 were proposed but with the end to procurement of Saturn and Apollo hardware, there was no capability to support these. The near-disaster of Apollo 13, where an oxygen tank explosion nearly doomed all three astronauts, helped to recapture national attention and concern. Although missions up to Apollo 20 were planned, Apollo 17 was the last mission to fly under the Apollo banner. The program ended because of budget cuts (in part due to the Vietnam War) and the desire to develop a reusable space vehicle.

Other early missions

Although the vast majority of NASA's budget has been spent on human spaceflight, there have been many robotic missions instigated by the space agency. In 1962 the Mariner 2 mission was launched and became the first spacecraft to make a flyby of another planet – in this case Venus. The Ranger, Surveyor, and Lunar Orbiter missions were essential to assessing lunar conditions before attempting Apollo landings with humans on board. Later, the two Viking probes landed on the surface of Mars and sent color images back to Earth, but perhaps more impressive were the Pioneer and particularly Voyager missions that visited Jupiter, Saturn, Uranus and Neptune sending back scientific information and color images. Having lost the moon race, the Soviet Union had, along with the USA, changed its approach. On July 17, 1975 an Apollo craft (finding a new use after the cancelling of planned lunar flights) was docked to the Soviet Soyuz 19 spacecraft, in the Apollo-Soyuz Test Project. Although the Cold War would last many more years, this was a critical point in NASA's history and much of the international co-operation in space exploration that exists today has its genesis with this mission. America's first space station, Skylab, occupied NASA from the end of Apollo until the late 1970s.

Shuttle era

Skylab 1981 ]] The space shuttle became the major focus of NASA in the late 1970s and the 1980s. Planned to be a frequently launchable and mostly reusable vehicle, four space shuttles were built by 1985. The first to launch, Columbia did so on April 12, 1981. The shuttle was not all good news for NASA – flights were much more expensive than initially projected, and even after the 1986 Challenger disaster highlighted the risks of space flight, the public again lost interest as missions appeared to become mundane. Work began on Space Station Freedom as a focus for the manned space programme but within NASA there was argument that these projects came at the expense of more inspiring unmanned missions such as the Voyager probes. The Challenger disaster aside the late 1980s marked a low point for NASA. Nonetheless, the shuttle has been used to launch milestone projects like the Hubble Space Telescope (HST). The HST was created with a relatively small budget of $2 billion but has continued operation since 1990 and has delighted both scientists and the public. Some of the images it has returned have become near-legendary, such as the groundbreaking Hubble Deep Field images. The HST is a joint project between ESA and NASA, and its success has paved the way for greater collaboration between the agencies. In 1995 Russian-American interaction would again be achieved as the Shuttle-Mir missions began, and once more a Russian craft (this time a full-fledged space station) docked with an American vehicle. This cooperation continues to the present day, with Russia and America the two biggest partners in the largest space station ever built – the International Space Station (ISS). The strength of their cooperation on this project was even more evident when NASA began relying on Russian launch vehicles to service the ISS following the 2003 Columbia disaster, which grounded the shuttle fleet for well over two years. Costing over one hundred billion dollars, it has been difficult at times for NASA to justify the ISS. The population at large have historically been hard to impress with details of scientific experiments in space, preferring news of grand projects to exotic locations. Even now, the ISS cannot accommodate as many scientists as planned. During much of the 1990s, NASA was faced with shrinking annual budgets due to Congressional belt-tightening in Washington, DC. In response, NASA's ninth administrator, Daniel S. Goldin, pioneered the "faster, better, cheaper" approach that enabled NASA to cut costs while still delivering a wide variety of aerospace programs (Discovery Program). That method was criticized and re-evaluated following the twin losses of Mars Climate Orbiter and Mars Polar Lander in 1999.

NASA's future

Mars Polar Lander and the planned crew and heavy lift launch vehicles]] NASA's most publicly-inspiring mission of recent years has probably been the Mars Pathfinder mission of 1997. Newspapers around the world carried images of the lander dispatching its own rover, Sojourner, to explore the surface of Mars in a way never done before at any extra-terrestrial location. Less publicly acclaimed but performing science from 1997 to date (2005) has been the Mars Global Surveyor orbiter. Since 2001, the orbiting Mars Odyssey has been searching for evidence of past or present water and volcanic activity on the red planet. NASA expects to continue exploring the Red Planet with more spacecraft such as the Mars Reconnaissance Orbiter, which will reach Mars in 2006. The Space Shuttle Columbia disaster in 2003, which killed the crew of six American and one Israeli astronaut, and caused a 29-month hiatus in space shuttle flights, triggered a serious re-examination of NASA's priorities. The U.S. government, various scientists, and the public all considered the future of the space program. On January 14, 2004, ten days after the landing of Mars Exploration Rover Spirit, President George W. Bush announced a new plan for NASA's future, dubbed the Vision for Space Exploration. According to this plan, humankind will return to the moon by 2020, and set up outposts as a testbed and potential resource for future missions. The space shuttle will be retired in 2010 and the Crew Exploration Vehicle will replace it by 2014, capable of both docking with the ISS and leaving the Earth's orbit. The future of the ISS is somewhat uncertain – construction will be completed, but beyond that is less clear. Although the plan initially met with skepticism from Congress, in late 2004 Congress agreed to provide start-up funds for the first year's worth of the new space vision. Hoping to spur innovation from the private sector, NASA established a series of Centennial Challenges, technology prizes for non-government teams, in 2004. The Challenges include tasks that will be useful for implementing the Vision for Space Exploration, such as building more efficient astronaut gloves.

Criticisms

Some commentators, such as Mark Wade, note that NASA has suffered from a 'stop-start' approach to its human spaceflight programs. The Apollo spacecraft and Saturn family of launch vehicles were abandoned in 1970 after billions of dollars had been spent on their development. In 2004 the U.S. Government proposed eventually replacing the Shuttle with a Crew Exploration Vehicle that would allow the agency to again send astronauts to the Moon. Despite the reduction of its budget following project Apollo, NASA has maintained a top-heavy bureaucracy resulting in inflated costs and compromised hardware. Crew Exploration Vehicle on October 31, 1998.]] Currently, the ISS relies on the Shuttle fleet for all major construction shipments. The Shuttle fleet has lost two spacecraft and fourteen astronauts in two disasters in 1986 and 2003. While the 1986 loss was made up with a Shuttle built from replacement parts, NASA does not plan to build another shuttle to replace the second loss. (But see also CEV.) The ISS, which was intended to have a crew of seven as of 2005, now has a skeleton crew of two, causing many intended research projects to be delayed. Other nations that have invested heavily in the space station's construction, such as the members of the European Space Agency, are fearful that the ISS's fate will soon match the fate of Skylab. As of 2005, however, all of the European and Japanese contributions to the ISS are years behind development schedule themselves.

NASA spaceflight missions

Human spaceflight

- Mercury program
- Gemini program
- Apollo program
- Skylab
- Space Shuttle
- International Space Station (working together with ESA, Rosviakosmos and JAXA)
- Project Constellation

Robotic space missions

- Earth Observing
- Upper Atmosphere Research Satellite
- TIMED (Thermosphere Ionosphere Mesosphere Energetics and Dynamics)
- Lunar missions
- Ranger
- Surveyor
- Lunar Orbiter
- Clementine
- Lunar Prospector
- Mercury missions
- Mariner 10
- MESSENGER
- Venus missions
- Mariner 2, 5 and 10
- Pioneer Venus
- Magellan
- Mars missions
- Mariner 4, 6, 7, 8 and 9
- Viking 1 and 2
- Mars Observer
- Mars Pathfinder
- Mars Climate Orbiter
- Mars Polar Lander
- Mars Global Surveyor
- 2001 Mars Odyssey
- Mars Exploration Rovers
- Mars Reconnaissance Orbiter
- Phoenix Lander (Planned for 2007)
- Mars Science Laboratory (Planned for 2009)
- Jupiter missions
- Pioneer 10
- Galileo
- Juno
- Saturn missions
- Cassini-Huygens together with ESA
- Multi-planet missions
- Pioneer 11 – Jupiter and Saturn
- Mariner 10 – Venus and Mercury
- Voyager 1 – Jupiter and Saturn
- Voyager 2 – Jupiter, Saturn, Uranus and Neptune
- New Horizons (Planned for 2006) – Jupiter, Pluto and Kuiper Belt
- Asteroidal/cometary missions
- NEAR Shoemaker
- Deep Space 1
- Stardust
- Deep Impact
- Dawn (Planned for 2006)
- Proposed or canceled planetary-asteroid missions
- JIMO (cancelled)
- CRAF (cancelled)
- NetLanders (cancelled)
- Pluto Kuiper Express (cancelled; New Horizons is replacement)
- Titan Explorer (proposed)
- Neptune Orbiter (proposed)
- Sun observing missions
- SOHO – ESA partnership
- Ulysses – ESA partnership
- Great Observatories for Space Astrophysics
- Hubble Space Telescope – ESA partnership
- Compton Gamma Ray Observatory
- Chandra X-ray Observatory
- Spitzer Space Telescope (formerly known as the Space Infrared Telescope Facility, SIRTF)
- Other observatories
- COBE
- FUSE
- Infrared Astronomical Satellite
- James Webb Space Telescope – ESA partnership
- WMAP

List of NASA administrators

# T. Keith Glennan (1958–1961) # James E. Webb (1961–1968) # Thomas O. Paine (1969–1970) # James C. Fletcher (1971–1977) # Robert A. Frosch (1977–1981) # James M. Beggs (1981–1985) # James C. Fletcher (1986–1989) # Richard H. Truly (1989–1992) # Daniel S. Goldin (1992–2001) # Sean O'Keefe (2001–2005) # Michael Griffin (2005–)

Field installations

In addition to headquarters in Washington, D.C., NASA has field installations at:
- Ames Research Center, Moffett Field, California
- Dryden Flight Research Center, Edwards, California
- John H. Glenn Research Center at Lewis Field, Cleveland, Ohio
- Goddard Space Flight Center, Greenbelt, Maryland
- Goddard Institute for Space Studies, New York, New York
- Independent Verification and Validation Facility, Fairmont, West Virginia
- Wallops Flight Facility, Wallops Island, Virginia
- Jet Propulsion Laboratory, near Pasadena, California
- Deep Space Network stations:
- Goldstone Deep Space Communications Complex, Barstow, California
- Madrid Deep Space Communication Complex, Madrid, Spain
- Canberra Deep Space Communications Complex, Canberra, Australian Capital Territory
- Lyndon B. Johnson Space Center, Houston, Texas
- White Sands Test Facility, Las Cruces, New Mexico
- John F. Kennedy Space Center, Florida
- Langley Research Center, Hampton, Virginia
- George C. Marshall Space Flight Center, Huntsville, Alabama
- Michoud Assembly Facility, New Orleans, Louisiana
- John C. Stennis Space Center, Bay St. Louis, Mississippi

Awards and decorations

NASA presently bestows a number of medals and decorations to astronauts and other NASA personnel. Some awards are authorized for wear on active duty military uniforms. Current NASA awards are as follows:
- Congressional Space Medal of Honor
- NASA Distinguished Public Service Medal
- NASA Distinguished Service Medal
- NASA Equal Employment Opportunity Medal
- NASA Exceptional Achievement Medal
- NASA Exceptional Administrative Achievement Medal
- NASA Exceptional Bravery Medal
- NASA Exceptional Engineering Achievement Medal
- NASA Exceptional Scientific Achievement Medal
- NASA Exceptional Service Medal
- NASA Exceptional Technological Achievement Medal
- NASA Outstanding Leadership Medal
- NASA Public Service Medal
- NASA Space Flight Medal

Related legislation

- 1958 – National Aeronautics and Space Administration PL 85-568 (passed on July 29)
- 1961 – Apollo mission funding PL 87-98 A
- 1970 – National Aeronautics and Space Administration Research and Development Act PL 91-119
- 1984 – National Aeronautics and Space Administration Authorization Act PL 98-361
- 1988 – National Aeronautics and Space Administration Authorization Act PL 100-685
- NASA Budget 1958–2005 in 1996 Constant Year Dollars

External links

General

- [http://www.nasa.gov NASA Home Page]
- [http://www.nasawatch.com NASA Watch]
-

Further research

- [http://history.nasa.gov/series95.html NASA History Series Publications]
- [http://history.nasa.gov/SP-40

Ares Vallis

Valley

Hollows

Famous valleys

Extraterrestrial valleys

See also

Mars

Mythology

Physical characteristics

Atmosphere

Geology

Topography

Canals

Ice lakes

The moons of Mars

The exploration of Mars

Nomenclature

Early nomenclature

Modern nomenclature

Observation of Mars

Appearance

Martian meteorites

Life on Mars

The Mars flag

Mars in fiction

See also

References

External links

Water on Mars

Mars exploration

Ancient Greek

Dialects of Ancient Greek

Sound changes

Sounds

Vowels

Short vowels

Long Vowels

Consonants

Consonant classes

Consonant contractions

Compensatory lengthening

Augment

Reduplication

Grammatical forms

Nouns

Alpha Declension

Ares

Consorts/Children

Ares in Neopaganism

See also:

External link

References

NASA

Vision and mission

History

Space Race

Apollo program

Other early missions

Shuttle era

NASA's future

Criticisms

NASA spaceflight missions

Human spaceflight

Robotic space missions

List of NASA administrators

Field installations

Awards and decorations

Related legislation

See also

Other space agencies

External links

General

Further research