Planet-hunters set for big bounty
Rocky planets, possibly with conditions suitable for life, may be more common than previously thought in our galaxy, a study has found.
New evidence suggests more than half the Sun-like stars in the Milky Way could have similar planetary systems.
There may also be hundreds of undiscovered worlds in outer parts of our Solar System, astronomers believe.
Future studies of such worlds will radically alter our understanding of how planets are formed, they say.
New findings about planets were presented at the American Association for the Advancement of Science (AAAS) in Boston.
Nasa telescope
Michael Meyer, an astronomer from the University of Arizona, said he believed Earth-like planets were probably very common around Sun-like stars.
“Our observations suggest that between 20% and 60% of Sun-like stars have evidence for the formation of rocky planets not unlike the processes we think led to planet Earth,” he said. “That is very exciting.”
Mr Meyer’s team used the US space agency’s Spitzer space telescope to look at groups of stars with masses similar to the Sun.
They detected discs of cosmic dust around stars in some of the youngest groups surveyed.
The dust is believed to be a by-product of rocky debris colliding and merging to form planets.
Nasa’s Kepler mission to search for Earth-sized and smaller planets, due to be launched next year, is expected to reveal more clues about these distant undiscovered worlds.
Frozen worlds
Some astronomers believe there may be hundreds of small rocky bodies in the outer edges of our own Solar System, and perhaps even a handful of frozen Earth-sized worlds.
Speaking at the AAAS meeting, Nasa’s Alan Stern said he thought only the tip of the iceberg had been found in terms of planets within our own Solar System.
More than a thousand objects had already been discovered in the Kuiper belt alone, he said, many rivalling the planet Pluto in size.
“Our old view, that the Solar System had nine planets will be supplanted by a view that there are hundreds if not thousands of planets in our Solar System,” he told BBC News.
He said many of these planets would be icy, some would be rocky, and there might even be objects with the same mass as Earth.
“It could be that there are objects of Earth-mass in the Oort cloud (a band of debris surrounding our planetary system) but they would be frozen at these distances,” Dr Stern added.
“They would look like a frozen Earth.”
Goldilocks zone
Excitement about finding other Earth-like planets is driven by the idea that some might contain life or perhaps, centuries from now, allow human colonies to be set up on them.
The key to this search, said Debra Fischer of San Francisco State University, California, was the “Goldilocks zone”.
This refers to an area of space in which a planet is “just the right distance” from its parent star so that its surface is not-too-hot or not-too-cold to support liquid water.
“To my mind there are two things we have to go after: we have to find the right mass planet and it has to be at the right distance from the star,” she said.
The AAAS meeting concludes on Monday.
via bbc
Planet hunters find ’super-Earth’
Planet hunters have discovered an icy “super-Earth” circling a distant star.
International astronomers suspect it is a bare, icy, rocky world, much colder than the Earth and 13 times its mass.
The planet was spotted last April but details have only just been revealed in a paper submitted to Astrophysical Journal Letters.
The extra-solar planet is one of a mere handful detected using a novel technique called microlensing.
The planet orbits a star about half as big as our Sun, positioned some 9,000 light-years away. At -201C, it is one of the coldest extra-solar planets to be discovered.
Andrew Gould, professor of astronomy at Ohio State University, US, was one of the first people to discover it.
He said the find has two main implications.
“First, this icy ’super-Earth’ dominates the region around its star that in our Solar System is populated by the gas-giant planets, Jupiter and Saturn,” he said.
“We’ve never seen a system like this before because we’ve never had the means to find them.
“And second, these icy ’super-Earths’ are pretty common. Roughly, 35% of all stars have them.”
Brightening effect
Professor Gould is leader of the Microlensing Follow-up Network (MicroFUN) collaboration.
It is one of several international groups looking for Earth-like planets in planetary systems other than our own using the phenomenon called gravitational microlensing.
The technique is an indirect way of obtaining information about large celestial objects that are too dim to see.
When a massive object such as a star crosses the path of a background star, it acts like a powerful lens, gravitationally bending and magnifying the light rays from the more distant star.
The object’s gravity amplifies the starlight, causing it to brighten as the body passes in front of the star.
This can be observed by telescopes on Earth as a brightening and fading effect, as the lens star floats across the face of the background star.
Neptune-mass
Clues to the presence of the planet were first seen last April by a Polish astronomy project led by Professor Andrzej Udalski from Warsaw University.
When Gould and Udalski realised the star was brightening extremely quickly one night, they alerted the duty astronomer at the MDM Observatory in Arizona.
“It was four in the morning,” Gould recalled, “I was very excited and frantic to get someone to observe that star.”
Astronomers in Arizona took more than 1,000 measurements of the event, which, coupled with software models, confirmed the presence of a Neptune-mass planet, 13 times heavier than Earth.
Gould suspects the planet is a bare, icy Earth-like one, a sort of cold “super-Earth”, although he cannot be certain.
“We can’t really tell for sure,” he said. “If we start getting more statistics on this type of planet, we could piece together a better story.”
Extraterrestrial life
Since the 1990s, astronomers have discovered some 170 extra-solar, or exoplanets, a planet which orbits a star other than the Sun.
There is great interest in finding extrasolar planets that are like the Earth, since these could, in theory, have the right conditions for supporting life.
In January, a new planet 5.5 times the mass of the Earth - the smallest yet - became the third exoplanet to be detected by the microlensing technique.
Tim Naylor, professor of astrophysics at Exeter University, UK, said microlensing had great promise for the future.
“It holds out the promise that we will discover many Earth-sized planets with this technique,” he told the BBC News website.
via bbc
Goldfish memory myth busted
A 15-year-old South Australian school student has busted the myth that goldfish have a three second memory.
Rory Stokes, from the Australian Science and Mathematics School in Adelaide, conducted an experiment to test the commonly held theory that goldfish have short memory spans.
He was also keen to open people’s minds to the cruelty of keeping fish in small tanks.
“We are told that a goldfish has a memory span of less than three seconds and that no matter how small its tank is, it will always discover new places and objects,” Rory said.
“I wanted to challenge this theory as I believe it is a myth intended to make us feel less guilty about keeping fish in small tanks.”
Rory’s experiment involved teaching a small group of fish to swim to a beacon by establishing a memory connection between the beacon and food.
Over a period of three weeks, he placed a beacon in the water at feeding time each day, waited 30 seconds and then sprinkled fish food around the beacon.
The time taken for the fish to swim to the beacon reduced dramatically, from more than one minute for the first few feeds to less than five seconds by the end of the three weeks.
Following the initial three-week period, Rory removed the beacon from the feeding process.
Six days later, he once again placed the beacon in the water and despite not seeing it for almost a week, the fish swam to the beacon in 4.4 seconds, showing they had remembered the association between food and the beacon for at least six days.
“My results strongly showed that goldfish can retain knowledge for at least six days,” Rory said.
“They can retain that knowledge indefinitely if they use it regularly.”
Rory also conducted a number of other experiments to show goldfish were capable of negotiating a simple maze, by having them move onto a second beacon if they found no food at the first.
“My experiments showed that goldfish have the mental capabilities to learn and remember fairly complex concepts and they can retain that knowledge for at least a number of days,” he said.
Australian Science and Mathematics School principal Jim Davies said the series of experiments were an excellent example of science investigation made fun.
via news.com.au
Reference: The goldfish, Carassius auratus, was one of the earliest fish to be domesticated, and is still one of the most commonly kept aquarium fish and water garden fish. A relatively small member of the carp family, the goldfish is a domesticated version of a dark-gray/brown carp native to East Asia. It was first domesticated in China and introduced to Europe in the late 17th century.
Goldfish may grow to a maximum length of 23 inches (59 cm) and a maximum weight of 9.9 pounds (4.5 kg), although this is rare; few goldfish reach even half this size. The oldest recorded goldfish lived to 49 years, but most household goldfish generally live only six to eight years, due to being kept in bowls. A group of goldfish is known as a troubling.
Archaeologist ‘Strikes Gold’ With Finds Of Ancient Nasca Iron Ore Mine In Peru
A Purdue University archaeologist discovered an intact ancient iron ore mine in South America that shows how civilizations before the Inca Empire were mining this valuable ore
“Archaeologists know people in the Old and New worlds have mined minerals for thousands and thousands of years,” said Kevin J. Vaughn, an assistant professor of anthropology who studies the Nasca civilization, which existed from A.D. 1 to A.D. 750. “Iron mining in the Old World, specifically in Africa, goes back 40,000 years. And we know the ancient people in Mexico, Central America and North America were mining for various materials. There isn’t much evidence for these types of mines.
“What we found is the only hematite mine, a type of iron also known as ochre, recorded in South America prior to the Spanish conquest. This discovery demonstrates that iron ores were important to ancient Andean civilizations.”
In 2004 and 2005, Vaughn and his team excavated Mina Primavera, which is located in the Ingenio Valley of the Andes Mountains in southern Peru. The research team performed field checks and collected some samples in 2006 and 2007.
The researchers determined that the mine is a human-made cave that was first created around 2,000 years ago. An estimated 3,710 metric tons was extracted from the mine during more than 1,400 years of use. The mine, which is nearly 700 cubic meters, is in a cliffside facing a modern ochre mine.
Vaughn hypothesizes that the Nasca people used the red-pigmented mineral primarily for ceramic paints, but they also could have used it as body paint, to paint textiles and even to paint adobe walls. The Nasca civilization is known for hundreds of drawings in the Nasca Desert, which are known as the Nasca-Lines and can only be seen from the air, and for an aqueduct system that is still used today.
Vaughn and his team discovered a number of artifacts in the mine, including corncobs, stone tools, and pieces of textiles and pottery. The age of the items was determined by radiocarbon dating, a process that determines age based on the decay of naturally occurring elements.
“Archaeologists have a very good sequence of pottery from this region, so I can look at most pots from this region and determine a date within a century that is based on stylistic changes of the pottery,” Vaughn said. “Even before the dating, we knew this was an ancient mine because of the ceramic pieces. These very small fragments, about the size of a penny, had distinct designs on them that are characteristic of the early Nasca civilization.”
The artifacts from the excavation are being curated by the Instituto Nacional de Cultura of Peru at its museum in Ica, Peru.
Now that there is archaeological evidence that ancient cultures in the Andes were mining iron ore, it is important to give credit to New World civilizations, Vaughn said.
“Even though ancient Andean people smelted some metals, such as copper, they never smelted iron like they did in the Old World,” he said. “Metals were used for a variety of tools in the Old World, such as weapons, while in the Americas, metals were used as prestige goods for the wealthy elite.”
This excavation was part of Vaughn’s Early Nasca Craft Economy Project, a multiyear National Science Foundation-funded study of Nasca ceramic production and distribution. The project’s goal is to better understand the origins of inequality and political economy in this ancient culture.
Vaughn says material scientists and engineers, as well as mineralogists, will be interested in this discovery.
“This study of mining is a great example of how archaeology bridges the social and physical sciences,” he said.
The National Science Foundation and the Heinz Foundation funded the Mina Primavera excavation. Next, Vaughn will be excavating a habitation site that has a 4,000-year occupation in hopes of understanding the long-term settlement history of the region.
“I hope to continue surveying for mines and mining-related sites in the region, and hopefully undertake additional excavations at the mine,” he said.
The findings of the excavation are published in December’s Journal of the Minerals, Metals & Materials Society.
by Purdue University
A large U.S. spy satellite has lost power and could hit the Earth in late February or March, government officials said Saturday.
The satellite, which no longer can be controlled, could contain hazardous materials, and it is unknown where on the planet it might come down, they said. The officials spoke on condition of anonymity because the information is classified as secret.
“Appropriate government agencies are monitoring the situation,” said Gordon Johndroe, a spokesman for the National Security Council, when asked about the situation after it was disclosed by other officials. “Numerous satellites over the years have come out of orbit and fallen harmlessly. We are looking at potential options to mitigate any possible damage this satellite may cause.”
He would not comment on whether it is possible for the satellite to be perhaps shot down by a missile. He said it would be inappropriate to discuss any specifics at this time.
A senior government official said that lawmakers and other nations are being kept apprised of the situation.
Such an uncontrolled re-entry could risk exposure of U.S. secrets, said John Pike, a defense and intelligence expert. Spy satellites typically are disposed of through a controlled re-entry into the ocean so that no one else can access the spacecraft, he said.
Pike also said it’s not likely the threat from the satellite could be eliminated by shooting it down with a missile, because that would create debris that would then re-enter the atmosphere and burn up or hit the ground.
Pike, director of the defense research group GlobalSecurity.org, estimated that the spacecraft weighs about 20,000 pounds and is the size of a small bus. He said the satellite would create 10 times less debris than the Columbia space shuttle crash in 2003.
As for possible hazardous material in the spacecraft, Pike said it might contain beryllium, a light metal with a high melting point that is used in the defense and aerospace industries. Breathing beryllium can lead to chronic, incurable respiratory problems.
Jeffrey Richelson, a senior fellow with the National Security Archive, said the spacecraft likely is a photo reconnaissance satellite. Such eyes in the sky are used to gather visual information from space about adversarial governments and terror groups, including construction at suspected nuclear sites or militant training camps. The satellites also can be used to survey damage from hurricanes, fires and other natural disasters.
The largest uncontrolled re-entry by a NASA spacecraft was Skylab, the 78-ton abandoned space station that fell from orbit in 1979. Its debris dropped harmlessly into the Indian Ocean and across a remote section of western Australia.
In 2000, NASA engineers successfully directed a safe de-orbit of the 17-ton Compton Gamma Ray Observatory, using rockets aboard the satellite to bring it down in a remote part of the Pacific Ocean.
In 2002, officials believe debris from a 7,000-pound science satellite smacked into the Earth’s atmosphere and rained down over the Persian Gulf, a few thousand miles from where they first predicted it would plummet.
by Associated Press
Charles Baldwin, a retired environmental-health engineer, explains his role in developing the biohazard symbol, which is now showing up everywhere.
I was working with the Dow Chemical company at the time, in 1966, developing containment systems for the Cancer Institute at the National Institutes of Health. And it became obvious to us that there were a lot of different so-called warning symbols in the various laboratories that we visited, but there was no standardization. We saw a need for this kind of a symbol and proceeded to develop some symbols with the help of the Dow marketing people — the package-design department, I think it was called. The only parameters that I set down for them to noodle through were, it had to be unique and something that would be striking enough that it would be remembered. We wanted something that was memorable but meaningless, so we could educate people as to what it means.
”We tested the sample symbols across the country — the marketing department had survey groups to test different labels for Dow products. There were half a dozen of our original symbols in this survey of 24 different symbols. The rest were recognizable, like the peanut man for Planter’s peanuts, the Texaco star, the Shell Oil symbol, the Red Cross and the swastika. They were asked to look at them and then asked to guess at what each one meant. The biohazard symbol got the fewest guesses. Then we went back one week later to the same set of people and the same set of symbols, plus 36 more common ones, and asked them which of these did they remember the best. And they picked out the biohazard symbol.
”The color was blaze orange, one of the colors chosen in Arctic exploration as being the most visible under the most conditions. It was three-sided because if it were on a box containing biohazardous material and the box was moved around, transported, it might wind up in different positions. Another thing — we needed something that was easily stenciled.
”The next major step was presenting it to the scientific community. I did that by writing a paper in the journal Science. The next was to get the authorization from the various people that would be using it. As soon as it was adopted by the Centers for Disease Control, the Occupational Safety and Health Administration and the National Institutes of Health, that’s pretty good acceptance. And that was it.
”Every time I go into the doctor’s office or the dentist’s office or a hospital anywhere, I’ve always got my eye out for it. Naturally, I’m proud of the fact that I was able to come up with something, or direct a program that evolved into this symbol that’s so widely recognized, so helpful. But I ran into a peculiar situation one time a couple years ago when someone was putting on a seminar on biohazards. As gifts for the participants, he devised a beautiful tie with little biohazard symbols all over it. This got me upset, and I sent him kind of a nasty letter saying this symbol was not designed to be used sartorially.”
by NY Times
Reference: A biological hazard or biohazard is an organism, or substance derived from an organism, that poses a threat to (primarily) human health. This can include medical waste, samples of a microorganism, virus or toxin (from a biological source) that can impact human health. It can also include substances harmful to animals. The term and its associated symbol is generally used as a warning, so that those potentially exposed to the substances will know to take precautions. There is also a biohazard HCS/WHMIS logo which utilizes the same symbol.
NASA Scientists Predict Black Hole Light Echo Show
It’s well known that black holes can slow time to a crawl and tidally stretch large objects into spaghetti-like strands. But according to new theoretical research from two NASA astrophysicists, the wrenching gravity just outside the outer boundary of a black hole can produce yet another bizarre effect: light echoes.
“The light echoes come about because of the severe warping of spacetime predicted by Einstein,” says Keigo Fukumura of NASA’s Goddard Space Flight Center in Greenbelt, Md. “If the black hole is spinning fast, it can literally drag the surrounding space, and this can produce some wild special effects.”
Fukumura and his NASA Goddard colleague Demosthenes Kazanas are presenting their research this Wednesday in a poster session at the American Astronomical Society’s 2008 winter meeting in Austin, Texas. They will also discuss their results in a press conference scheduled for 2:00 P.M. CST on Thursday.
Many black holes are surrounded by disks of searing hot gas that whirl around at nearly the speed of light. Hot spots within these disks sometimes emit random bursts of X-rays, which have been detected by orbiting X-ray observatories. But according to Fukumura and Kazanas, things get more interesting when they take into account Einstein’s general theory of relativity, which describes how extremely massive objects like black holes can actually warp and drag the surrounding space-time.
Many of these X-ray photons travel to Earth by taking different paths around the black hole. Because the black hole’s extreme gravity warps the surrounding spacetime, it bends the trajectories of the photons so they arrive here with a delay that depends on the relative positions of the X-ray flare, the black hole, and Earth.
Fukumura and Kazanas’ calculations, the delay between the photons is constant, independent of the source’s position. They discovered that for rapidly spinning black holes, about 75 percent of the X-ray photons arrive at the observer after completing a fraction of one orbit around the black hole, while the remaining photons travel the exact same fraction plus one or more full orbits.
“For each X-ray burst from a hot spot, the observer will receive two or more flashes separated by a constant interval, so even a signal made up from a totally random collection of bursts from hot spots at different positions will contain an echo of itself,” says Kazanas.
Though difficult to discern in the raw data, astronomers can use a Fourier analysis, or other statistical methods, to pick up these hidden echoes. Among other things, a Fourier analysis is a mathematical tool for extracting periodic behavior in a signal that might otherwise seem totally random. The echoes would appear as quasi-periodic oscillations (QPOs). An example of a QPO with a period of 10 seconds might exhibit peaks at 9, 21, 30, 39, 51, and 61 seconds.
If one considers a 10-solar-mass black hole that formed from a dying star, and if the black hole is spinning more than 95 percent of its maximum possible speed, the period of its QPOs would be about 0.7 milliseconds, corresponding to about 1,400 peaks per second, which is three times higher than any QPOs that have been detected around black holes. NASA’s Rossi X-ray Timing Explorer satellite could measure such high-frequency QPOs, but the signal would have to be very strong.
Detecting these high-frequency QPOs would do more than just confirm another prediction of Einstein’s theory. It would also provide a gold mine of information about the black hole itself. The frequency of the QPOs depends on the black hole’s mass, so detecting this echo effect would give astronomers an accurate way to measure the masses of black holes. In addition, notes Kazanas, “This echoes occur only if a black hole is spinning near its maximum possible speed, so it would tell astronomers that the black hole is spinning really fast.”
by NASA
Reference: A black hole is a region of space in which the gravitational field is so powerful that nothing can escape after having fallen past the event horizon. The name comes from the fact that even electromagnetic radiation (e.g. light) is unable to escape, rendering the interior invisible. However, black holes can be detected if they interact with matter outside the event horizon, for example by drawing in gas from an orbiting star. The gas spirals inward, heating up to very high temperatures and emitting large amounts of radiation in the process.
by NASA
FBI planning world’s largest biometric database
The FBI has announced it plans to assemble the world’s largest biometric database, nicknamed the Next Generation Identification system. Currently, the FBI stores fingerprints, facial features, and palm print characteristics at its facilities in Washington DC. The agency’s $1 billion dollar database, however, will hold far more information on any given person.
Moving forward, the FBI expects to make this comprehensive biometric database available to a wide variety of federal, state, and local agencies, all in the name of keeping American safe from terrorists (and illegal immigration). The FBI also intends to retain (upon employer request) the fingerprints of any employee who has undergone a criminal background check, and will inform the employer if the employee is ever arrested or charged with a crime.
Lofty goals are one thing, practical implementation is another. The biometric database the FBI envisions will rely heavily on realtime (or very nearly realtime) comparisons. According to the Washington Post, this could include general face recognition, specific feature comparison (notable scars, shape of the earlobe, etc), walking stride, speech patterns, and iris comparisons. To date, facial-recognition technology hasn’t exactly reshaped the face of law enforcement. A German study last year showed some progress in the technology—existing implementations proved more than 60 percent effective during the day—but accuracy fell to 10-20 percent at night. German law enforcement officials have stated they would accept a 0.1 percent error rate across a 24 hour period, which leaves current technology with quite a gap to close.
The FBI plans to work closely with the CITeR (Center for Identification Technology Research) research center to improve existing metrics and create new ones. CITeR is reportedly working on an iris scanner that can identify people at up to 15 feet as well as a facial-recognition scanner capable of identifying faces accurately at a range of up to 200 yards.
The FBI’s decision to implement this kind of tracking and identification system raises a number of concerns regarding citizen privacy , as well as serious questions about the accuracy of collected data. Any database that isn’t closely monitored and continuously updated will inevitably grow out-of-date. It’s also not clear that a biometric system of the type the FBI espouses couldn’t become confused simply by the natural aging process, weight loss, weight gain, injury, or permanent disability. While there are proven methods of identification that remain accurate even in the presence of such factors, none of them yield realtime results that can be immediately pegged as belonging to an individual even in a crowd of people.
Certain aspects of the FBI’s track record in recent years make this proposal even less attractive. In 2003, the FBI exempted its National Crime Information Center, the Central Records System, and the National Center for the Analysis of Violent Crime from subsection (e) (5) of the 1974 Privacy Act. That particular subsection mandates that each agency that maintains a system of records shall “maintain all records which are used by the agency in making any determination about any individual with such accuracy, relevance, timeliness, and completeness as is reasonably necessary to assure fairness to the individual in the determination.”
According to the FBI, discharging this duty conflicts with the agency’s primary purpose as a law enforcement organization, because it is “impossible to determine in advance what information is accurate, relevant, timely, and complete.” Information once thought innocuous may also eventually prove to be critical may eventually shed critical details as an investigation continues, and the restrictions of (e) (5) “would limit the ability of trained investigators and intelligence analysts to exercise their judgement in reporting on investigations and impede the development of criminal intelligence necessary for effective law enforcement.”
At this point, the FBI’s proposed biometric identification system contains no recourse for citizens who are misidentified, no formal method for the update and correction of biometric information, and no indication that citizens would even be allowed to view their own biometric profiles.
The organization’s technology track record is anything but good. The organization’s Trilogy project launched in 2000 as an effort to update the FBI’s IT infrastructure and create a new type of Virtual Case File (VCF) ended in collosal failure in 2005. The agency is currently working on a new, more ambitious system (codenamed Sentinel), but little information is available on how that project is progressing at this time. Once considered the definitive voice of bullet analysis, a six month investigation by CBS television show 60 Minutes and the Washington Post recently uncovered fundamental flaws in the FBI’s methodology and basic premises. As a result, evidence presented as fact for the past 40 years has now been called into serious question, simply because the FBI, which claimed it could match bullet fragments to similar bullets—right down to the very same box—never scientifically tested the basic premise.
Even in the best of scenarios, it’s unclear whether or not any national database of biometric information could be kept secure, updated, and available for citizen review. The FBI’s past history and the agency’s decision to remove itself from the requirements of the 1974 Privacy Act leave the current scenario far from ideal, and open the door for any number of misidentifications or abuses.
Wikipedia Reference: Biometrics (ancient Greek: bios =”life”, metron =”measure”) refers to two very different fields of study and application. The first, which is the older and is used in biological studies, including forestry, is the collection, synthesis, analysis and management of quantitative data on biological communities such as forests. Biometrics in reference to biological sciences has been studied and applied for several generations and is somewhat simply viewed as “biological statistics.”
More recently and incongruently, the term’s meaning has been broadened to include the study of methods for uniquely recognizing humans based upon one or more intrinsic physical or behavioral traits.
Some researchers, have coined the term behaviometrics for behavioral biometrics such as typing rhythm or mouse gestures where the analysis can be done continuously without interrupting or interfering with user activities.
Biometrics are used to identify the identity of an input sample when compared to a template, used in cases to identify specific people by certain characteristics.
possession-based: using one specific “token” such as a security tag or a card
knowledge-based :the use of a code or password.
Standard validation systems often use multiple inputs of samples for sufficient validation, such as particular characteristics of the sample. This intends to enhance security as multiple different samples are required such as security tags and codes and sample dimensions.
Biometric characteristics can be divided in two main classes, as represented in figure on the right:
physiological are related to the shape of the body. The oldest traits, that have been used for more than 100 years, are fingerprints. Other examples are face recognition, hand geometry and iris recognition.
behavioral are related to the behavior of a person. The first characteristic to be used, still widely used today, is the signature. More modern approaches are the study of keystroke dynamics and of voice.
Strictly speaking, voice is also a physiological trait because every person has a different pitch, but voice recognition is mainly based on the study of the way a person speaks, commonly classified as behavioral.
Other biometric strategies are being developed such as those based on gait (way of walking), retina, hand veins, ear recognition, facial thermogram, DNA, odor and palm prints.
Biometric systems
The diagram on right shows a simple block diagram of a biometric system. When such a system is networked together with telecommunications technology, biometric systems become telebiometric systems. The main operations a system can perform are enrollment and test. During the enrollment, biometric information from an individual is stored. During the test, biometric information is detected and compared with the stored information. Note that it is crucial that storage and retrieval of such systems themselves be secure if the biometric system is be robust. The first block (sensor) is the interface between the real world and our system; it has to acquire all the necessary data. Most of the times it is an image acquisition system, but it can change according to the characteristics desired. The second block performs all the necessary pre-processing: it has to remove artifacts from the sensor, to enhance the input (e.g. removing background noise), to use some kind of normalization, etc. In the third block features needed are extracted. This step is an important step as the correct features need to be extracted and the optimal way. A vector of numbers or an image with particular properties is used to create a template. A template is a synthesis of all the characteristics extracted from the source, in the optimal size to allow for adequate identifiability.
If enrollment is being performed the template is simply stored somewhere (on a card or within a database or both). If a matching phase is being performed, the obtained template is passed to a matcher that compares it with other existing templates, estimating the distance between them using any algorithm (e.g. Hamming distance). The matching program will analyze the template with the input. This will then be output for any specified use or purpose (e.g. entrance in a restricted area).
Astronauts test sex in space - but did the earth move?
US and Russian astronauts have had sex in space for separate research programmes on how human beings might survive years in orbit, according to a book published yesterday.
Pierre Kohler, a respected French scientific writer, says in The Final Mission: Mir, The Human Adventure that the subject is taboo both at Nasa and at mission control in Moscow, but that cosmic couplings have taken place.
“The issue of sex in space is a serious one,” he says. “The experiments carried out so far relate to missions planned for married couples on the future International Space Station, the successor to Mir. Scientists need to know how far sexual relations are possible without gravity.”
He cites a confidential Nasa report on a space shuttle mission in 1996. A project codenamed STS-XX was to explore sexual positions possible in a weightless atmosphere.
Twenty positions were tested by computer simulation to obtain the best 10, he says. “Two guinea pigs then tested them in real zero-gravity conditions. The results were videotaped but are considered so sensitive that even Nasa was only given a censored version.”
Only four positions were found possible without “mechanical assistance”. The other six needed a special elastic belt and inflatable tunnel, like an open-ended sleeping bag.
Mr Kohler says: “One of the principal findings was that the classic so-called missionary position, which is so easy on earth when gravity pushes one downwards, is simply not possible.”
Wikipedia Reference: Sex in space is distinguished mainly by the absence of gravity (unless artificial gravity is created in the space ship) which leads to some difficulties surrounding the performing of most sexual activities. Because no certain sexual intercourse in space is known to have occurred, the topic is hotly disputed to clarify its potential impact on human beings in the isolated, confined, and hazardous environment of space. However, the ongoing discussions often include several speculations (e.g., about the STS-47 mission, on which married astronauts Mark C. Lee and Jan Davis flew), and even hoaxes, such as Document 12-571-3570.
It is assumed that the nervous and vestibular systems may fail to develop properly in individuals growing up in a low or zero gravity environment, and that this would have implications for space-born humans making the trip to Earth though the possibility of human pregnancy under spacecraft conditions is currently uncertain.
Though NASA generally avoids the topic, it has examined animal and plant reproduction in several experiments.
Science fiction and popular science writer Isaac Asimov made conjectures in writing about what sex would be like in the weightless environment of space, in 1973. He anticipated some of the benefits of engaging in sex in an environment of microgravity.
A leading Soviet research facility in the field of space medicine, The Institute of Biomedical Problems, has been involved for decades in the sex-related studies of living species in space. The Institute’s interest in topic began in the early 1960s, when it noticed a difference in behavior between two dogs that had flown in space, Veterok and Ugolyok. Ugolyok, unlike Veterok, maintained quite a healthy libido during his longer-than-average life span.
A 1976 article reported that an exposure of Wistar rats to 22 days of weightlessness and other space flight factors induced no morphological changes in the spermatogenic tissue or disorders in the spermatogenic process of the rats, and the offspring of the male “space rats” was normal in all aspects.
Regarding human sex, Dr. Anna Goncharova said that if crew members are just colleagues and friends, one should never impose on them any intimate relations for the sake of their psycho-emotional stability. It was rumored that the unhappy marriage of Soviet cosmonauts Valentina Tereshkova and Andrian Nikolayev was in part instigated by the pressure of the IBP.
Zero-gravity sex is a common topic in science-fiction.
In his book Honeymoon in Space published in 1901 George Griffith described a phallic spaceship with “curtains of ribbed steel” going deeper and deeper through the Solar System while the young maid exclaims how she wants to see more and more.
In the James Bond film Moonraker, James Bond (played by Roger Moore), and the token Bond girl, Dr. Holly Goodhead, have sex in the cargo bay of the Moonraker 5 Space Shuttle in one scene.
The comedy Moving Violations (1985) suggests the main characters, played by actors John Murray and Jennifer Tilly, have an intimate encounter in a weightlessness simulator.
The Sci-fi horror Supernova (2000) featured sex between several of the characters in zero-gravity areas of the Medical Ship.
Private Media Group filmed a brief scene the space-themed pornographic film The Uranus Experiment in a Russian aircraft flying a parabolic track (similar to NASA’s Vomit Comet). The Uranus Experiment features around 20 seconds of actors Sylvia Saint and Nick Lang (who portray astronauts living on a space station) having sex in freefall. The scene was controversially nominated for a Nebula Award, but did not win.
Evidence for a parallel universe?
Today’s article is not about DNA, although its far-reaching implications prompted us to share this story with our readers.
Last August, astronomers working on the analysis of data being acquired by NASA’s WMAP (Wilkinson Microwave Anisotropy Probe) satellite announced that they found a huge void in the universe. A void is a region of space that has much less material (stars, nebulae, dust and other material) than the average. Since our universe is relatively heterogeneous, empty spaces are not rare, but in this case the enormous magnitude of the hole is way outside the expected range. The hole found in the constellation of Eridanus is about a billion light years across, which is roughly 10,000 times as large as our galaxy or 400 times the distance to Andromeda, the closest “large” galaxy.
The dimension of the hole is so big that at first glance, it results impossible to explain under the current cosmological theories, although scientists put forward some explanations based on certain theoretical models that might predict the existence of “giant knots” in space known as topological defects.
However, University of North Carolina at Chapel Hill physics Professor Laura Mersini-Houghton made a staggering claim. She says, “Standard cosmology cannot explain such a giant cosmic hole” and goes further with the ground-breaking hypothesis that the huge void is “… the unmistakable imprint of another universe beyond the edge of our own“.
The idea of alternative, or parallel universes has been around for quite a while and has provided considerable inspiration for Sci-Fi literature and sparked endless philosophical debate, but although begin seriously considered within the scientific realm it never crossed the limits of speculative of purely theoretical grounds. Perhaps until now. If Mersini-Houghton is right, Eridanus’ giant hole would be the first experimental evidence for the existence of another universe. The implications of this possibility are obviously of huge importance for everybody, but it also has further relevance for the astrophysics community as it would bring support for the hotly debated string theory and other central debates.
But Mersini-Houghton and colleagues’ theory of entangled universes make testable predictions, providing the opportunity to confirm or refute the claim as more data arrive to the astronomers’ computers. Her model predicts the existence of two voids rather than one, one in each hemisphere of our universe. The one that has been found by WMAP’s data lies in the Northern hemisphere. They expect new data will show a second similar void in the Southern side. This and other cutting-edge experimental projects testing Mersini-Houghton’s ideas will tell us whether a new era in cosmological thinking has indeed arrived.
Great ‘cosmic nothingness’ found
Astronomers have found an enormous void in space that measures nearly a billion light-years across.
It is empty of both normal matter - such as galaxies and stars - and the mysterious “dark matter” that cannot be seen directly with telescopes.
The “hole” is located in the direction of the Eridanus constellation and has been identified in data from a survey of the sky made at radio wavelengths.
The discovery will be reported in a paper in the Astrophysical Journal.
Previous sky surveys that have traced the large-scale structure of the nearby Universe have long shown, for example, how the clustering of galaxies is strung into vast filaments and sheets that are separated by great gaps.
But the void discovered by a University of Minnesota team is about 1,000 times the volume of what would be expected in typical cosmic gaps.
“It’s hard even for astronomers to picture how big these things are,” conceded Minnesota’s Professor Lawrence Rudnick.
“If you were to travel at the speed of light, it would take you several years to get to the nearest stars in our own Milky Way galaxy; but if you were to go to this hole and enter one side, you’d have to travel for a billion years before you would get to the other side,” he told BBC News.
The void is roughly 6-10 billion light-years away and takes a sizeable chunk out of the visible Universe in its direction.
Dark evidence
The team used data from the US National Radio Astronomy Observatory’s VLA Sky Survey (NVSS) to make its discovery. The VLA - which stands for Very Large Array - is a collection of 27 radio telescopes in New Mexico.
The finding is said to fit neatly with observations of the Universe’s “oldest light” - the famous Cosmic Microwave Background (CMB) radiation, the study of which has earned several scientists the Nobel Prize.
This is the radiation that comes from just 380,000 years after the Big Bang when the Universe had cooled to such a degree that hydrogen atoms could exist. Before that time, scientists say, the Universe would have been so hot that matter and light would have been “coupled” - the cosmos would have been opaque.
Today, this light shines at microwave wavelengths at a frigid -270C; and observations of the CMB made by Nasa’s Wilkinson Microwave Anisotropy Probe show a particular “cold spot” in the direction of the newly identified void.
The explanation for this may lie in the enigmatic “dark energy” that scientists know so little about but which is said to be accelerating the expansion of the Universe.
Light particles passing through the void would be expected to lose a little more energy than those passing through space cluttered with matter - if dark energy is stretching the Universe apart at a faster and faster rate.
Scientists refer to this as the Integrated Sachs-Wolfe Effect and a corresponding “warm spot” in the CMB associated with an area of space dominated by a supercluster of galaxies was identified some years ago.
“In essence, this latest study gives us a very elegant demonstration of the existence of dark energy in a way which is very convincing,” commented Professor Carlos Frenk, the director of the Institute for Computational Cosmology at Durham University, UK.
“We keep getting evidence for dark energy, this component of the Universe which is so dominant, and yet we still have only a tiny glimmer of what it could be.”
The reason the void exists is not known. “That’s going to be a challenge for people that work on the development of structure in the Universe. It’s a very hot topic in the cosmology right now,” said Professor Rudnick.
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Universe
The Universe is defined as the summation of all particles and energy that exist and the space-time in which all events occur. Based on observations of the portion of the Universe that is observable, physicists attempt to describe the whole of space-time, including all matter and energy and events which occur, as a single system corresponding to a mathematical model. Our universe is also defined as one component part of a larger Multiverse.
The generally accepted scientific theory which describes the origin and evolution of the Universe is Big Bang cosmology, which describes the expansion of space from an extremely hot and dense state of unknown characteristics. The Universe underwent a rapid period of cosmic inflation that flattened out nearly all initial irregularities in the energy density; thereafter the universe expanded and became steadily cooler and less dense. Minor variations in the distribution of mass resulted in hierarchical segregation of the features that are found in the current universe; such as clusters and superclusters of galaxies. There are more than one hundred billion (1011) galaxies in the Universe, each containing hundreds of billions of stars, with each star containing about 1057 atoms of hydrogen.
There are also non-scientific investigations that explore and describe the universe as a whole with their own separate cosmologies.
Multiverse
A multiverse (or meta-universe) is the hypothetical set of multiple possible universes (including our universe) that together comprise all of physical reality. The different universes within a multiverse are sometimes called parallel universes. The structure of the multiverse, the nature of each universe within it and the relationship between the various constituent universes, depend on the specific multiverse hypothesis considered.
Multiverses have been hypothesized in cosmology, physics, philosophy, theology, and fiction, particularly in science fiction and fantasy. The specific term “multiverse,” which was coined by William James, was popularized by science fiction author Michael Moorcock. In these contexts, parallel universes are also called “alternative universes,” “quantum universes,” “parallel worlds,” “alternate realities,” “alternative timelines,” etc.
The possibility of many universes raises various scientific, philosophical, and theological questions.
