Searching for habitability on Red Planet: Phoenix will dredge the Martian landscape with its robotic arm and onboard instruments.[ILLUSTRATION OMITTED] A NEW EMISSARY EMISSARY. One who is sent from one power or government into another nation for the purpose of spreading false rumors and to cause alarm. He differs from a spy. (q.v.) FROM EARTH IS SET TO parachute onto Mars on May 25, making it the first craft to land on the Red Planet's north polar region North Polar Region See Polar Regions. and the first since the 1970s built to find life-friendly places. NASA's $386-million Phoenix Mars Lander features a robotic arm--similar to a backhoe--that will dig trenches up to half a meter deep in the frigid soil, scraping and scooping up samples of ice that previous satellite studies indicate lie just a few centimeters beneath the surface. Phoenix will deliver those samples to onboard detectors--eight miniature ovens, four laboratory wet cells and a mass spectrometer--to determine if the region contains water, complex organic compounds and sources of energy that might support life. The main question the craft seeks to answer: "Is there any place on Mars at all where life could exist today?" says Phoenix principal investigator Peter Smith of the University of Arizona (body, education) University of Arizona - The University was founded in 1885 as a Land Grant institution with a three-fold mission of teaching, research and public service. in Tucson. "Phoenix represents a significant step in understanding water on Mars Psychedelic rock and electronic music group from Quebec City (Québec, Canada), Water on Mars (WOM) is the instrument of its leader Philippe Navarro, guitarist, vocalist, arranger, producer and principal author and composer of the trio. ," notes planetary scientist Jack Mustard of Brown University in Providence, R.I. In following up on the discovery by the Mars Odyssey mission of water-ice just beneath the polar surface, Phoenix will "quantitatively analyze the mineral and volatile constituents of the soil," he says. "It will also measure isotopes of carbon Carbon (C) Standard atomic mass: 12.0107(8) u Table nuclide symbol Z(p) N(n) isotopic mass (u) half-life nuclear spin representative isotopic composition (mole fraction) range of natural variation (mole fraction) , oxygen, hydrogen and nitrogen, which will be unique and important measurements for understanding processes relevant to habitability Fitness for occupancy. The requirement that rented premises, such as a house or apartment, be reasonably fit to occupy. A Warranty of habitability is an implied promise by a landlord of residential premises that such premises are fit for human habitation. ." Phoenix got its moniker (1) A name, title or alias. See alias. (2) A COM object that is used to create instances of other objects. Monikers save programmers time when coding various types of COM-based functions such as linking one document to another (OLE). See COM and OLE. because it inherited instruments from the Mars Surveyor Lander, canceled in 2000, as well as detectors similar to those on the Mars Polar Lander The Mars Polar Lander was part of the NASA Mars Surveyor '98 program, which consisted of two spacecraft launched separately, the Mars Climate Orbiter (formerly the Mars Surveyor '98 Orbiter) and the Mars Polar Lander (formerly the Mars Surveyor '98 Lander). , lost in 1999. Scheduled to land at 68[degrees] N, the same latitude as northern Alaska, Phoenix will function for three months but might last twice as long, until the shorter, colder days of winter hamper the solar-powered craft. In searching for an existing habitat on the Red Planet, Phoenix revives an endeavor attempted with the 1976 Viking missions. "Viking made the assumption that there was life on Mars Scientists have long speculated about the possibility of life on Mars owing to the planet's proximity and similarity to Earth. It remains an open question whether life exists on Mars now, or existed there in the past. , and they were going to characterize that life," Smith says. In contrast to Viking, Phoenix takes more of a generalist approach. "We don't assume there is life, we are just looking for Looking for In the context of general equities, this describing a buy interest in which a dealer is asked to offer stock, often involving a capital commitment. Antithesis of in touch with. a habitable zone," Smith says. "We don't measure DNA DNA: see nucleic acid. DNA or deoxyribonucleic acid One of two types of nucleic acid (the other is RNA); a complex organic compound found in all living cells and many viruses. It is the chemical substance of genes. . We don't measure proteins." Mustard notes that Mars' "nasty radiation environment" makes the likelihood next to nil that life is present in the near surface. "It's best to build first towards habitability--when, where and how--and then move toward life detection on the basis of those results," he says. Phoenix "is not sexy in that it does not look for microbes, but it's very important." To seek actual life, Smith says, a future, more sophisticated craft will require a drill that can penetrate the ice down to a depth of 20 to 30 meters, Mustard says. "Phoenix sets the stage for those future missions." Phoenix's ovens, each about the size of a ballpoint pen's ink cartridge, will slowly heat ice samples up to 1,000[degress] Celsius. In contrast, Viking flash-heated material to 500[degress] C. The expanded temperature range is critical for identifying various organic compounds and monitoring the transition from solid to liquid to gas, Smith notes. Those materials that vaporize va·por·ize v. To convert or be converted into a vapor. Vaporize To dissolve solid material or convert it into smoke or gas. at temperatures from about 300[degress] C to 600[degress] C "could be the complex organic compounds we're looking for," Smith says. Vaporization vaporization, change of a liquid or solid substance to a gas or vapor. There is fundamentally no difference between the terms gas and vapor, but gas is used commonly to describe a substance that appears in the gaseous state under standard conditions of at higher temperatures may signify organic compounds delivered to the Martian surface by asteroids This is a list of numbered minor planets, nearly all of them asteroids, in sequential order. As of late September 2007 there are 164,612 numbered minor planets, and many more not yet numbered. Most asteroids are ordinary and not particularly noteworthy. or comets. The gases will then be fed into a mass spectrometer, which will measure the concentration of specific atoms and molecules at concentrations as low as 10 parts per billion. [ILLUSTRATION OMITTED] The robotic arm will also deliver single soil samples to each of four pre-warmed beakers that contain a soaking solution. After a day of stirring, soaking and measuring the beaker's contents, the sample will be frozen overnight. Upon thawing, the sample will be exposed to reagents that can test for carbonates and sulfates. In addition to digging and analyzing soil and ice samples, Phoenix's instruments will offer a commanding and highly detailed view of its landing site. "The surface itself may be absolutely fascinating without doing anything but just looking at it," Smith says. Like a pair of eyes, twin cameras atop the craft's 2-meter-long mast will take a 3-D infrared and visible-light panorama of the arctic terrain to reveal features as small as a few millimeters across. Optical and atomic force microscopes will take close-ups of soil and water-ice samples, recording features as small as one-hundredth the width of a human hair--the tiniest details ever taken on the Red Planet. "That's the kind of imaging I'm thinking about these days--the whole picture," from kilometers to about 100 nanometers, Smith says. "I don't know Don't know (DK, DKed) "Don't know the trade." A Street expression used whenever one party lacks knowledge of a trade or receives conflicting instructions from the other party. what Mars is going to offer us, and we've protected ourselves by bringing a lot of instruments that can open up the story." Shooting infrared and green lasers into the Martian atmosphere, Phoenix will also examine the atmosphere's density and composition up to 20 kilometers in altitude. The data will provide information about the formation, duration and movement of clouds, fog and dust plumes that can't easily be seen from space. "This is unexplored territory as far as atmospheric science goes," Smith says. "We've taken pictures of these clouds, but we don't know how high they are." By coordinating with two spacecraft flying overhead, the team will be able to locate dust storms before they reach the landing site. "We'll do a complete study of dust storms on Mars for the first time," Smith says. Back Story [ILLUSTRATION OMITTED] 1976 Viking 1 and 2 landers, sent to find life, landed on Mars and returned historic images--but no microbes. [ILLUSTRATION OMITTED] 1997 The Mars Pathfinder watched over the Sojourner Rover, which found clues suggesting past liquid water. [ILLUSTRATION OMITTED] 1998 to 2006 Mars Global Surveyor The Mars Global Surveyor (MGS) was a US spacecraft developed by NASA and the Jet Propulsion Laboratory and launched November 1996. It began the United States's return to Mars after a 20-year absence. orbited the planet. It watched the weather, photographed the surface and mapped ideal landing sites. [ILLUSTRATION OMITTED] 2004 to present The geologist-rovers Opportunity and Spirit continue to collect detailed data from the surface. [ILLUSTRATION OMITTED] May 25, 2008 The Mars Phoenix Lander is set to land on Mars, looking for possibly life-friendly areas. [ILLUSTRATION OMITTED] 2009 The Mars Science Laboratory This article or section documents a scheduled or expected spaceflight. Details may change as the launch date approaches or more information becomes available. would assemble a miniature lab with the types of instruments now only at large labs on Earth. |
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