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- MOON TO PROVIDE A STEPPING STONE TO MARS AND BEYOND
- THE SEARCH FOR MORE EARTHS
- LOS ALAMOS COMPUTERS PROBE HOW GIANT PLANETS FORMED
- DOOM AND GLOOM BY 2100
- ESA CONSIDERS THE NEXT STEP IN ASSESSING THE RISK FROM NEAR-EARTH OBJECTS
- AMMONIA ON MARS COULD MEAN LIFE
- NEW WORLDS OF WORDS
- INFLATABLE SPACE OUTPOSTS: CASH DOWN ON HIGH HOPES
- NEW MARTIAN METEORITE FOUND IN ANTARCTICA
AM: Taking a leap into the future, let's assume the technology, biology, sociology, and politics have all combined to create a unique sub-race of humanity on Mars. Generations of human beings have now been born, grown, bred and died on Mars. Who are these Martians? RZ: In 1893, the great historian Frederick Jackson Turner wrote: "To the frontier the American intellect owes its striking characteristics. That coarseness of strength combined with acuteness and inquisitiveness; that practical inventive turn of mind, quick to find expedients; that masterful grasp of material things, lacking in the artistic but powerful to effect great ends; that restless, nervous energy; that dominant individualism, working for good and evil, and withal that buoyancy and exuberance that comes from freedom—these are the traits of the frontier." I think that says it all. The pioneers of the martian frontier will be the Americans of the future. Read the original article at http://www.astrobio.net/news/article1074.html. MOON TO PROVIDE A STEPPING STONE TO MARS AND BEYOND By Brian Berger From Space.com
From Universe Today 12 July 2004 When astronomers first realized that the stars in the sky were like our Sun, only more distant, they wondered if those stars had planets too. And if they have planets, is there life? Intelligent life? There's an answer—yes or no—but we don't know it yet. NASA and the European Space Agency are working on a series of space and ground-based observatories that may help get an answer soon. In just a decade, you could gaze into the night sky, locate a star, and know that there's life there. Life could be everywhere. Read the full article at http://www.universetoday.com/am/publish/search_for_more_earths.html. LOS ALAMOS COMPUTERS PROBE HOW GIANT PLANETS FORMED Los Alamos National Laboratory release 13 July 2004 Nearly five billion years ago, the giant gaseous planets Jupiter and Saturn formed, apparently in radically different ways. So says a scientist at the University of California's Los Alamos National Laboratory who created exhaustive computer models based on experiments in which the element hydrogen was shocked to pressures nearly as great as those found inside the two planets. Working with a French colleague, Didier Saumon of Los Alamos' Applied Physics Division created models establishing that heavy elements are concentrated in Saturn's massive core, while those same elements are mixed throughout Jupiter, with very little or no central core at all. The study, published in this week's Astrophysical Journal, showed that refractory elements such as iron, silicon, carbon, nitrogen and oxygen are concentrated in Saturn's core, but are diffused in Jupiter, leading to a hypothesis that they were formed through different processes. Saumon collected data from several recent shock compression experiments that have showed how hydrogen behaves at pressures a million times greater than atmospheric pressure, approaching those present in the gas giants. These experiments—performed over the past several years at U.S. national labs and in Russia—have for the first time permitted accurate measurements of the so-called equation of state of simple fluids, such as hydrogen, within the high-pressure and high-density realm where ionization occurs for deuterium, the isotope made of a hydrogen atom with an additional neutron. Working with T. Guillot of the Observatoire de la Cote d'Azur, France, Saumon developed about 50,000 different models of the internal structures of the two giant gaseous planets that included every possible variation permitted by astrophysical observations and laboratory experiments. "Some data from earlier planetary probes gave us indirect information about what takes place inside Saturn and Jupiter, and now we're hoping to learn more from the Cassini mission that just arrived in Saturn's orbit," Saumon said. "We selected only the computer models that fit the planetary observations." Jupiter, Saturn and the other giant planets are made up of gases, like the sun. They are about 70 percent hydrogen by mass, with the rest mostly helium and small amounts of heavier elements. Therefore, their interior structures were hard to calculate because hydrogen's equation of state at high pressures wasn't well understood. Saumon and Guillot constrained their computer models with data from the deuterium experiments, thereby reducing previous uncertainties for the equation of state of hydrogen, which is the central ingredient needed to improve models of the structures of the planets and how they formed. "We tried to include every possible variation that might be allowed by the experimental data on shock compression of deuterium," Saumon explained. By estimating the total amount of the heavy elements and their distribution inside Jupiter and Saturn, the models provide a better picture of how the planets formed through the accretion of hydrogen, helium and solid elements from the nebula that swirled around the sun billions of years ago. "There's been general agreement that the cores of Saturn and Jupiter are different," Saumon said. "What's new here is how exhaustive these models are. We've managed to eliminate or quantify many of the uncertainties, so we have much better confidence in the range within which the actual data will fall for hydrogen, and therefore for the refractory metals and other elements. "Although we can't say our models are precise, we know quite well how imprecise they are," he added. These results from the models will help guide measurements to be taken by Cassini and future proposed interplanetary space probes to Jupiter. Los Alamos National Laboratory is operated by the University of California for the National Nuclear Security Administration (NNSA) of the U.S. Department of Energy and works in partnership with NNSA's Sandia and Lawrence Livermore national laboratories to support NNSA in its mission. Los Alamos develops and applies science and technology to ensure the safety and reliability of the U.S. nuclear deterrent; reduce the threat of weapons of mass destruction, proliferation and terrorism; and solve national problems in defense, energy, environment and infrastructure. Contact: Jim Danneskiold Phone: 505-667-1640 E-mail: jdanneskiold@lanl.gov Additional articles on this subject are available at: http://www.astrobio.net/news/article1080.html http://www.spacedaily.com/news/extrasolar-04t.html
By Julie Wakefield From Scientific American
ESA release 14 July 2004 On 9 July 2004, the Near-Earth Object Mission Advisory Panel recommended that ESA place a high priority on developing a mission to actually move an asteroid. The conclusion was based on the panel’s consideration of six near-Earth object mission studies submitted to the Agency in February 2003. Of the six studies, three were space-based observatories for detecting NEOs and three were rendezvous missions. All addressed the growing realization of the threat posed by Near-Earth Objects (NEOs) and proposed ways of detecting NEOs or discovering more about them from a close distance. A panel of six experts, known as the Near-Earth Object Mission Advisory Panel (NEOMAP) assessed the proposals. Alan Harris, German Aerospace Centre (DLR), Berlin, and Chairman of NEOMAP, says, "The task has been very difficult because the goalposts have changed. When the studies were commissioned, the discovery business was in no way as advanced as it is now. Today, a number of organizations are building large telescopes on Earth that promise to find a very large percentage of the NEO population at even smaller sizes than visible today." As a result, the panel decided that ESA should leave detection to ground-based telescopes for the time being, until the share of the remaining population not visible from the ground becomes better known. The need for a space-based observatory will then be re-assessed. The panel placed its highest priority on rendezvous missions, and in particular, the Don Quijote mission concept. "If you think about the chain of events between detecting a hazardous object and doing something about it, there is one area in which we have no experience at all and that is in directly interacting with an asteroid, trying to alter its orbit," explains Harris. 
Artist's impression of the Don Quijote Mission. The Don Quijote mission concept will do this by using two spacecraft, Sancho and Hidalgo. Both are launched at the same time but Sancho takes a faster route. When it arrives at the target asteroid it will begin a seven-month campaign of observation and physical characterization during which it will land penetrators and seismometers on the asteroid’s surface to understand its internal structure. Sancho will then watch as Hidalgo arrives and smashes into the asteroid at very high speed. This will provide information about the behavior of the internal structure of the asteroid during an impact event as well as excavating some of the interior for Sancho to observe. After the impact, Sancho and telescopes from Earth will monitor the asteroid to see how its orbit and rotation have been affected. Harris says, "When we do actually find a hazardous asteroid, you could imagine a Don Quijote-type mission as a precursor to a mitigation mission. It will tell us how the target responds to an impact and will help us to develop a much more effective mitigation mission." 
Hidalgo impacts with the asteroid while Sancho, with an attitude appropriate to its name, retreats to a safe distance to observe the impact without taking unnecessary risk. Image credit: ESA/Deimos Space. On 9 July, the findings were presented to the scientific and industrial community. Representatives of other national space agencies were also invited in the hope that they will be interested in developing a joint mission, based around this concept. Andrés Galvez, ESA’s Advanced Concepts Team and technical officer for the NEOMAP report says, "This report gives us a solid foundation to define programmatic priorities and an implementation strategy, in which I also hope we are joined by international partners". With international cooperation, a mission could be launched as early as 2010-2015. Read the original news release at http://www.esa.int/esaCP/SEMZO8M26WD_index_0.html. Additional articles on this subject are available at: http://www.astrobio.net/news/article1082.html http://www.space.com/scienceastronomy/scitues_don_quijote_040713.html http://www.spacedaily.com/news/deepimpact-04k.html AMMONIA ON MARS COULD MEAN LIFE By David Whitehouse From BBC News Online
From Astrobiology Magazine 15 July 2004 The Oxford English Dictionary announced this week the latest new terms to bolster its role as the classic overseer of the English language. As sandwiched between the new additions for "arborist" (a tree surgeon) and the Indian term "batchmate" (a classmate) is a new word hardly a decade old. Accepted this week to the dictionary is "astrobiology", defined as "the branch of biology concerned with the discovery or study of life on other planets or in space." Derivative forms are the adjective, "astrobiological" and noun, "astrobiologist". Counted among the Oxford entries in what has "long been considered the ultimate reference work in English lexicography," the 20-volume compendium has declared officially that "the search for life elsewhere" needs a definition. Since astrobiology came into its own from the earliest international science gatherings, the usage of the term has been discussed. One group of advocates considered whether astrobiology needed to be distinct from exobiology, an antecedent field that has occasionally been used as a synonym. Exobiology journals existed already and conferences discussed the origin of life or how microbes might survive in space. One distinction between the prefixes "exo-" and "astro-" centered on whether exobiology treated extraterrestrial life only and not broader issues of terrestrial climate or evolution on Earth as precursors to understanding life elsewhere. So would exobiology consider new methods of planet discovery, for instance, as being biological enough for their journals? Astrobiology journals seemed willing to fill any gaps, if a topic was somehow linked to the discovery of life elsewhere. Other examples to distinguish the two branches might show themselves on an invited speakers list. An astrobiologist might be an invited speaker if they could reference geological research to determine the age of the Earth or track planetary evolution if it might help quantify the probability of finding another Earth-like world. An exobiologist seemed less likely to be a geologist or astrophysicist by training. At those early meetings, another group questioned the literal interpretation of "astrobiology" as meaning "the biology of stars". Was astrobiology about stellar reproduction? The question was posed half in jest, but might prove semantically troublesome, particularly if the Greek prefix "astro", or "stars", might mislead an international scientific community just being introduced to controversial issues in such a nascent and cross-disciplinary field. Few could argue that a fiery star itself was ever habitable, so labeling astrobiology as "the biology of stars" had literal implications for introductory teachers, students and dictionary editors. Academic writers, including a few now published by the Oxford University Press (OUP), have bandied around the term, astrobiology, as formally including "the scientific search for life in the universe, and the current level of scientific understanding of how life begins, grows, and becomes intelligent in our Solar System and beyond." The jacket cover on a 2002 OUP publication called astrobiology, "one of the most exciting new fields in science." Whether the relation between the rising number of astrobiology courses— and the textbooks to support those graduates—has a bearing on its now popular usage is not clear, but as the oldest English-speaking university in the world, Oxford now seems willing to survey the field from the ground up. Ever since the European university system formally divided departmental responsibilities in science to the big three—physics, chemistry and biology—many cross-fertilizations like astrophysics and earth science have arisen to confound those divisions. But few of these candidate disciplines can count such a wide array of practitioners as can the broad cadre of astrobiologists. Among them are included cosmologists, computer theorists, engineers, robotocists, geologists, radio astronoomers, organic and biological chemists. Given the rapid advances in the frontiers of genetics, no shortage of microbiologists and DNA experts have broadened their view of their own fields to include consideration of how the primordial soup might have been stirred elsewhere in the universe. One question in defining astrobiology remained: exactly what disciplines did it exclude? A picture may help. Each scientific branch has its defining image. Physicists split the atom, chemists built the periodic table, and biologists have the DNA molecule. Should astrobiologists have a logo? Conducting a survey on the street might link astrobiology to alien searches. But as a discipline, astrobiology seemed less slanted towards a particular humanoid shape of an alien lifeform or even an enormous radio dish pointed skywards. If such a vast field could be reduced to a single picture, then one candidate might be a picture of an ocean on another world. Just finding a great sea would imply biology to many, since as ingredients go, liquid water has preeminence in defining conditions suitable for life. Indeed, in looking back at our own planet from space—the "Pale Blue Dot"—Carl Sagan used the Voyager probe's photograph of Earth from over 3 billion miles to highlight both the vastness of space and the relative importance of water for life here. In 1998, NASA's Associate Administrator Wesley Huntress, Jr., stated, "Wherever liquid water and chemical energy are found, there is life. There is no exception." A working definition for astrobiology therefore might evolve in practice to mean: wherever a source of water is found outside Earth, a curious astrobiologist is likely to be found lurking. An alternative but less pictorial view of how a branch of science gets its definition relies on knowing its particular tools. In this view, a carpenter is known by his hammer and saw, not by the house he builds. Among the sciences, do astrobiologists have a characteristic method of measurement? Astrobiology of course inherits all the rich scientific timeline of instrument developments, but critics have wondered if any search for life could ever pass a statistical test. On a planetary scale, only one example of an inhabited world is known to us or even available to scientific conjecture. This criticism is blunted if more new planets around other stars reveal themselves and as more extreme environments for life on Earth prove fertile. One hundred such new worlds have been identified just since the term astrobiology came into NASA usage. If any natural phenomenon can be measured, it can safely be bet on to enter the wider halls of science. So the argument goes according to advocates and pioneers in the field, astrobiology has too many things to measure, not too few. After all, if twenty-five percent of all stars also host a larger solar system of their own, then current estimates for the number of planets just in our own galaxy may top one billion yet undiscovered worlds. Beyond the semantics, few would argue the search for life lacks frontiers to explore. One key to taking the next step in measurement for astrobiologists in fact is another of this week's new entries in the Oxford English Dictionary: the word, "bioindicator". The term refers formally to an organism used as an indicator of the quality of an ecosystem. So coincidentally, the roots of astrobiology may deepen as a discipline if more bioindicators are explored on Earth and elsewhere. This week's entry of the term "astrobiology" in the Oxford English Dictionary is laudable to scientists who debated its earliest boundaries. Few students may actually rely on a dictionary to describe a branch of science, but the event itself symbolizes a coinage that is likely to outlast just a single generation of graduates. As with any working science, ultimately the field is defined by the topics of research treated in its journals and conferences. Indeed a popular topic among SETI researchers addresses how best to communicate with another civilization, when we cannot assimilate each other's meanings—or even new usages of shared Greek roots like astro- and -biologia. In the world of new words, astrobiology appears poised this week to become another word for finding new worlds. Read the original article at http://www.astrobio.net/news/article1079.html. INFLATABLE SPACE OUTPOSTS: CASH DOWN ON HIGH HOPES By Leonard David From Space.com
NASA release 2004-232 20 July 2004 While rovers and orbiting spacecraft scour Mars searching for clues to its past, researchers have uncovered another piece of the red planet in the most inhospitable place on Earth—Antarctica. The new specimen was found by a field party from the U.S. Antarctic Search for Meteorites program (ANSMET) on December 15, 2003, on an ice field in the Miller Range of the Transantarctic Mountains, roughly 750 km (466 miles) from the South Pole. This 715.2-gram (1.6-pound) black rock, officially designated MIL 03346, was one of 1358 meteorites collected by ANSMET during the 2003-2004 austral summer. Discovery of this meteorite occurred during the second full field season of a cooperative effort funded by NASA and supported by the National Science Foundation (NSF) to enhance recovery of rare meteorite types in Antarctica, in the hopes new martian samples would be found. Scientists at the Smithsonian Institution's National Museum of Natural History involved in classification of Antarctic finds said the mineralogy, texture and the oxidized nature of the rock are unmistakably martian. The new specimen is the seventh recognized member of a group of martian meteorites called the nakhlites, named after the first known specimen that fell in Nakhla, Egypt, in 1911. Like the other martian meteorites, MIL 03346 is a piece of the red planet that can be studied in detail in the laboratory, providing a critical "reality check" for use in interpreting the wealth of images and data being returned by the spacecraft currently exploring Mars. Following the existing protocols of the U.S. Antarctic meteorite program, scientists from around the world will be invited to request samples of the new specimen for their own detailed research. 
View of MIL 03346 showing black fusion crust with vugs as well as lighter interior exposed on the left side. Nakhlites are significant among the known martian meteorites for several reasons. Thought to have originated within thick lava flows that crystallized on Mars approximately 1.3 billion years ago, and sent to Earth by a meteorite impact about 11 million years ago, the nakhlites are among the older known martian meteorites. As a result they bear witness to significant segments of the volcanic and environmental history of Mars. The U.S. Antarctic Meteorite program is a cooperative effort jointly supported by NSF, NASA and the Smithsonian Institution. Antarctic field work is supported by grants from NASA and NSF to Case Western Reserve University, Cleveland; initial examination and curation of recovered Antarctic meteorites is supported by NASA at the astromaterials curation facilities at Johnson Space Center in Houston; and initial characterization and long-term curation of Antarctic meteorite samples is supported by NASA and the Smithsonian Institution at the National Museum of Natural History in Washington. 
Plane polarized view of MIL 03346, 2 showing clinopyroxene crystals and dark mesostasis. Details concerning initial characterization of the specimen and sample availability are available through a special edition of the Antarctic Meteorite Newsletter, to be immediately released on the Web at http://curator.jsc.nasa.gov/curator/antmet/amn/amn.htm. The edition also will be mailed to researchers worldwide. Contacts: Donald Savage NASA Headquarters, Washington, DC Phone: 202-358-1727 Leslie Fink National Science Foundation, Arlington, VA Phone: 703-292-5395
Smithsonian Institution, Washington, DC Phone: 202-357-2627
Case Western Reserve University, Cleveland Phone: 216-368-6070 Directory: projects -> marsbugs -> 2004 projects -> Rajinder Sachar Committee projects -> Cape Lookout National Seashore Historic Resource Study By projects -> Cape Lookout National Seashore Historic Resource Study By projects -> Revolutionizing Climate Modeling – Project Athena: a multi-Institutional, International Collaboration projects -> What is a Hurricane? projects -> General Information projects -> Press Information projects -> 1 Introduction 3 2 Designing an Embedded System 4 2004 -> Editor/Publisher 2004 -> Editor/Publisher Download 226.25 Kb. Share with your friends:
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