Pluto's Orbital Mysteries
The June 23 occultation will also reveal precisely where Pluto and Charon are relative to one another in the sky.
The data should help astronomers solve an orbital mystery that was revealed by the discovery of the two smaller moons Nix and Hydra almost six years ago.
"We once thought that Pluto and Charon orbited in simple ellipses. But, with the discovery of the small moons, we found they all pull on each other and affect each other in subtle ways," Young said.
Pinpointing the orbits more exactly will reveal the objects' masses—and will help astronomers plan observation strategies for the New Horizons spacecraft.
"Knowing the orbits better will help us refine where we aim our cameras—you don't want an image with half of an object out of the frame," explained NASA's Stern.
"Knowing the orbits more accurately will also make us more efficient, so we have time to do more things—and we're only going to be there once."
(Related: "Pluto is the Biggest Dwarf Planet After All?")
The June 27 Hydra occultation is especially exciting, team member Young added, because the small moon has been an elusive target for the past six years. With this round of observing, her team is hopeful that they'll finally be able to pinpoint Hydra's size.
"It's been very hard to do, because until recently we didn't know the orbit of Hydra relative to Pluto very well, and because the object is so small that we have a very small chance of being in Hydra's shadow" to observe it from the proper place on Earth, Young said.
Recent work with Hubble Space Telescope images has narrowed Hydra's position relative to Pluto to within tens of kilometers. With that information in hand, observations from the June 23 occultation can be analyzed in time to pinpoint where in Australia to place a telescope to be in Hydra's shadow four days later.
"By the time [astronomer] Marc Buie starts driving out of Alice Springs two days before the second occultation, we'll be able to tell him and his army of amateurs where to go."
Even with all the planning, NASA's Stern added, part of the allure is that no one's quite sure exactly what they'll see during the Pluto occultations.
"That's the great thing about astronomy," Stern said. "Sometimes when you unwrap a present, you really get a surprise gift."
(The Pluto occultation research is supported by the National Geographic Society's Committee for Research and Exploration, NASA's Planetary Astronomy program, NASA's New Horizons Mission, and the Southwest Research Institute.)
miercuri, 22 iunie 2011
marți, 21 iunie 2011
Albert Einstein
Albert Einstein birthday- Albert Einstein was born in March 14, 1879,Ulm, Germany and died April 18, 1955, Princeton, New Jersey, U.S.
Albert Einstein is such a great name in the history of science that his name must be included among the top most scientific minds the world has produced so far. His theories of relativity led to the entirely new dimension of thinking about time, matter , energy , and gravity. He own the noble prize for physics in 1921 for his explanation of the photoelectric effect.
At the age of 15, with poor grades in history, geography, and languages, he left school with no diploma and went to Milan to rejoin his family, who had recently moved to there from Germany because of his father’s business setbacks. Einstein resumed his education in physics and mathematics at the renowned Federal Polytechnic Academy of Zurich in Switzerland .After his graduation in the spring of 1900, he became a Swiss citizen. He worked as a mathematics teacher for two months and then he was employed as an examiner at the Swiss patent office in Bern. In 1903, Einstein married his university girl friend Mileva Maric.
Albert Einstein is such a great name in the history of science that his name must be included among the top most scientific minds the world has produced so far. His theories of relativity led to the entirely new dimension of thinking about time, matter , energy , and gravity. He own the noble prize for physics in 1921 for his explanation of the photoelectric effect.
Albert Einstein Family
In 1880, the year after Einstein’s birth , his family moved from Ulm to Munich, where Hermann Einstein, his father , and Jakob Einstein, his uncle , setup a small scale electrical plant and engineering works. During that time German schools were rigidly disciplined , which Einstein found intimidating and boring. Moreover, he showed very little scholastic ability. At the behest of his mother Einstein also studied music and learned violin which the used to play throughout his life for relaxation purpose.At the age of 15, with poor grades in history, geography, and languages, he left school with no diploma and went to Milan to rejoin his family, who had recently moved to there from Germany because of his father’s business setbacks. Einstein resumed his education in physics and mathematics at the renowned Federal Polytechnic Academy of Zurich in Switzerland .After his graduation in the spring of 1900, he became a Swiss citizen. He worked as a mathematics teacher for two months and then he was employed as an examiner at the Swiss patent office in Bern. In 1903, Einstein married his university girl friend Mileva Maric.
Einstein Discoveries-Theories
In 1905, at the age of 26 Einstein published five major research papers in a prestigious German physics journal . For his first paper he received a doctorate degree from the university of Zurich, thesis entitled “A new determination of Molecular Dimensions,”.
In his first paper he explained Brownian movement, the zigzag motion of microscopic particles in suspension, which is the random motion of molecules of the suspension medium as they bounce against the suspended particles.
His second paper laid the foundation for the photon, or quantum, theory of light. He suggested that light is composed of separate packets of energy, called quanta or photons, which exhibits some of the properties of particles and some of the properties of waves. In fact his paper redefined the theory of light. It also explained the theory of photoelectric effect, which is due to the emission of electrons from some solids when they are struck by light waves.
His third paper was linked to an essay which he wrote at the age of 16, known as “special theory of relativity.” He showed that how time and motion are relative to its observer, if the speed of light is constant and natural laws are the same everywhere in the universe –it was an complete novel idea of that time.
Einstein’s fourth paper was a mathematical addition to his third paper where he presented his famous formula , E=mc2 , known as the mass-energy relation. It says that the energy (E) inherent in a mass(m) equals the mass multiplied by the velocity of light squared(c2) .This equation proves that a small particle of matter is the equivalent of an enormous quantity of energy. This theory had helped him to be considered among the most eminent physicists of Europe during that time.
In his general theory of relativity, published in 1916, Einstein proposed that gravity is not a force, but a curved field in the space-time continuum that is created by the presence of mass.
In 1914 Einstein had accepted a position with the Prussian Academy of Sciences and moved to Berlin. During that time his wife and two sons were vacationing in Switzerland and with the eruption of World War I they were unable to return to Berlin. In fact this separation lead to divorce a few years later. Beginning in the 1920s Einstein tried to establish a mathematical relationship between electromagnetism and gravitation. He spent the rest of his life on this unsuccessful attempt to explain all of the properties of matter and energy in a single mathematical formula.
Einstein was a pacifist and an outspoken critic of German militarism. Einstein's view of humanity during the war period appears in a letter to a friend, the Austrian born Dutch physicist Paul Ehrenfest:“The ancient Jehovah is still abroad. Alas, he slays the innocent along with the guilty, whom he strikes so fearsomely blind that they can feel no sense of guilt.…We are dealing with an epidemic delusion which, having caused infinite suffering, will one day vanish and become a monstrous and incomprehensible source of wonderment to later generations.”
Einstein opposed war and violence and supported Zionism, the movement to establish a Jewish homeland in Palestine. In 1933 Nazis came to power in Germany ,they denounced his ideas, seized his property, and burned his books. That year he moved to the United States. In 1940 he became an American citizen.
In 1939, shortly before the outbreak of World War II in Europe, Einstein learned that two German chemists had split the uranium atom. Enrico Fermi, an Italian physicist who lived in the United States, proposed that a chain-reaction splitting of uranium atoms could release enormous quantities of energy. That same year Einstein wrote to President Franklin D. Roosevelt warning him that this scientific knowledge could lead to Germany's development of an atomic bomb. He suggested that the United States begin preparations for its own atomic bomb research. Einstein's urging led to the creation of the Manhattan Project and the development of the first two atomic bombs in 1945.
Einstein died in his sleep at Princeton Hospital, N.J., on April 18, 1955. On his desk found his last incomplete statement, written to honor Israeli Independence Day. It read in part: “What I seek to accomplish is simply to serve with my feeble capacity truth and justice at the risk of pleasing no one.” His contribution to man's understanding of the universe was matchless, and he will be regarded among the all time best scientists of science. Perhaps, realization of the vastness of our universe made him to comment, “Politics are for the moment. An equation is for eternity.”
In his first paper he explained Brownian movement, the zigzag motion of microscopic particles in suspension, which is the random motion of molecules of the suspension medium as they bounce against the suspended particles.
His second paper laid the foundation for the photon, or quantum, theory of light. He suggested that light is composed of separate packets of energy, called quanta or photons, which exhibits some of the properties of particles and some of the properties of waves. In fact his paper redefined the theory of light. It also explained the theory of photoelectric effect, which is due to the emission of electrons from some solids when they are struck by light waves.
His third paper was linked to an essay which he wrote at the age of 16, known as “special theory of relativity.” He showed that how time and motion are relative to its observer, if the speed of light is constant and natural laws are the same everywhere in the universe –it was an complete novel idea of that time.
Einstein’s fourth paper was a mathematical addition to his third paper where he presented his famous formula , E=mc2 , known as the mass-energy relation. It says that the energy (E) inherent in a mass(m) equals the mass multiplied by the velocity of light squared(c2) .This equation proves that a small particle of matter is the equivalent of an enormous quantity of energy. This theory had helped him to be considered among the most eminent physicists of Europe during that time.
In his general theory of relativity, published in 1916, Einstein proposed that gravity is not a force, but a curved field in the space-time continuum that is created by the presence of mass.
In 1914 Einstein had accepted a position with the Prussian Academy of Sciences and moved to Berlin. During that time his wife and two sons were vacationing in Switzerland and with the eruption of World War I they were unable to return to Berlin. In fact this separation lead to divorce a few years later. Beginning in the 1920s Einstein tried to establish a mathematical relationship between electromagnetism and gravitation. He spent the rest of his life on this unsuccessful attempt to explain all of the properties of matter and energy in a single mathematical formula.
Einstein was a pacifist and an outspoken critic of German militarism. Einstein's view of humanity during the war period appears in a letter to a friend, the Austrian born Dutch physicist Paul Ehrenfest:“The ancient Jehovah is still abroad. Alas, he slays the innocent along with the guilty, whom he strikes so fearsomely blind that they can feel no sense of guilt.…We are dealing with an epidemic delusion which, having caused infinite suffering, will one day vanish and become a monstrous and incomprehensible source of wonderment to later generations.”
Einstein opposed war and violence and supported Zionism, the movement to establish a Jewish homeland in Palestine. In 1933 Nazis came to power in Germany ,they denounced his ideas, seized his property, and burned his books. That year he moved to the United States. In 1940 he became an American citizen.
In 1939, shortly before the outbreak of World War II in Europe, Einstein learned that two German chemists had split the uranium atom. Enrico Fermi, an Italian physicist who lived in the United States, proposed that a chain-reaction splitting of uranium atoms could release enormous quantities of energy. That same year Einstein wrote to President Franklin D. Roosevelt warning him that this scientific knowledge could lead to Germany's development of an atomic bomb. He suggested that the United States begin preparations for its own atomic bomb research. Einstein's urging led to the creation of the Manhattan Project and the development of the first two atomic bombs in 1945.
Einstein died in his sleep at Princeton Hospital, N.J., on April 18, 1955. On his desk found his last incomplete statement, written to honor Israeli Independence Day. It read in part: “What I seek to accomplish is simply to serve with my feeble capacity truth and justice at the risk of pleasing no one.” His contribution to man's understanding of the universe was matchless, and he will be regarded among the all time best scientists of science. Perhaps, realization of the vastness of our universe made him to comment, “Politics are for the moment. An equation is for eternity.”
Global warming
Global warming
Global warming has become perhaps the most complicated issue facing world leaders. On the one hand, warnings from the scientific community are becoming louder, as an increasing body of science points to rising dangers from the ongoing buildup of human-related greenhouse gases — produced mainly by the burning of fossil fuels and forests. On the other, the technological, economic and political issues that have to be resolved before a concerted worldwide effort to reduce emissions can begin have gotten no simpler, particularly in the face of a global economic slowdown.Global talks on climate change opened in Cancún, Mexico, in late 2010 with the toughest issues unresolved, and the conference produced modest agreements. But while the measures adopted in Cancún are likely to have scant near-term impact on the warming of the planet, the international process for dealing with the issue got a significant vote of confidence.
The agreement fell well short of the broad changes scientists say are needed to avoid dangerous climate change in coming decades. But it laid the groundwork for stronger measures in the future, if nations are able to overcome the emotional arguments that have crippled climate change negotiations in recent years. The package, known as the Cancún Agreements, gives the more than 190 countries participating in the conference another year to decide whether to extend the frayed Kyoto Protocol, the 1997 agreement that requires most wealthy nations to trim their emissions while providing assistance to developing countries to pursue a cleaner energy future.
At the heart of the international debate is a momentous tussle between rich and poor countries over who steps up first and who pays most for changed energy menus.
In the United States, on Jan. 2, 2011, the Environmental Protection Agency imposed its first regulations related to greenhouse gas emissions. The immediate effect on utilities, refiners and major manufacturers will be small, with the new rules applying only to those planning to build large new facilities or make major modifications to existing plants. Over the next decade, however, the agency plans to regulate virtually all sources of greenhouse gases, imposing efficiency and emissions requirements on nearly every industry and every region.
President Obama vowed as a candidate that he would put the United States on a path to addressing climate change by reducing emissions of carbon dioxide and other greenhouse gas pollutants. He offered Congress wide latitude to pass climate change legislation, but held in reserve the threat of E.P.A. regulation if it failed to act. The deeply polarized Senate’s refusal to enact climate change legislation essentially called his bluff.
But working through the E.P.A. has guaranteed a clash between the administration and Republicans that carries substantial risks for both sides. The administration is on notice that if it moves too far and too fast in trying to curtail the ubiquitous gases that are heating the planet it risks a Congressional backlash that could set back the effort for years. But the newly muscular Republicans in Congress could also stumble by moving too aggressively to handcuff the Environmental Protection Agency, provoking a popular outcry that they are endangering public health in the service of their well-heeled patrons in industry.
You stay up all night on the PC typing and typing. No, you’re not hacking. You’re begging someone on IRC to teach you how to hack! Let’s look at the facts:
- You’re a luser and you’re annoying. No one likes you if you ask others how to hack without taking the least amount of initiative.
- You’re not worthy of any title even resembling hacker, cracker, phreaker, etc., so don’t go around calling yourself that! The more you do, the less likely you are to find someone willing to teach you how to hack (which is an infinitesimal chance, any way).
- You’re wasting your time (if you couldn’t infer that in the first place). Many real hackers (not those shitty script kiddies) spend all their insomniac hours reading and, yes even, HACKING! (Hacking doesn’t necessarily (but usually does) mean breaking into another system. It could mean just working on your own system, BUT NOT WINDOWS ’9x (unless you’re doing some really menacing registry shit, in which case, you’re kind of cool).)
- Practical Unix and Internet Security (Sec. Edition): This is mostly a book about how to secure Unix (if you don’t know what Unix is, either shoot yourself now, or read O’Reilly’s Learning the Unix OS), but half of learning to hack is learning a system from the inside out. How can you expect to hack a site (w/o using a kiddie script, which i must restate, is NOT hacking) if you don’t know how to use the system?!
- Linux Unleashed/Red Hat Linux Unleashed: these books are kind of cool. First of all, they come with Red Hat Linux (*sigh*, just go to www.linux.org and read everything there) Read everything you can from it.
- TCP/IP Blueprints: this will clear up a lot of things concerning TCP/IP.
- TCP/IP Administration: haven’t read it, but can’t wait to! (I’ve been bogged down by a lot of other REAL computer stuff).
Columbia shuttle
A NASA report on the last minutes of Space Shuttle Columbia cited problems with the crew's helmets, spacesuits and restraints, which resulted in "lethal trauma" to the seven astronauts aboard.
But the report also acknowledged that "the breakup of the crew module ... was not survivable by any currently existing capability."
The spacecraft broke up while re-entering Earth's atmosphere near the end of its mission on February 1, 2003.
The NASA report found the astronauts knew for about 40 seconds that they did not have control of the shuttle before they likely were knocked unconscious as Columbia broke apart around them.
The report also found that while crew members were wearing their pressurized suits, one astronaut did not have on a helmet, three were not wearing gloves and none lowered the visors before the module lost cabin pressure. One astronaut also was not seated.
"In this accident, none of those actions would have ultimately made any difference," said former shuttle program manager Wayne Hale, now a deputy NASA administrator.
The graphic, 400-page investigative report relied on video, recovered debris and medical findings, supplemented with computer modeling and analyses. It also includes many recommendations to make space travel safer for future astronauts.
A shuttle-program source told CNN the families of the astronauts who died were brought in specifically to look at the report and even in some cases to help with its preparation. The report took more than five years to complete.
"The members of this team have done an outstanding job under difficult and personal circumstances," said Johnson Space Center director Michael L. Coats. "Their work will ensure that the legacy of Columbia and her heroic crew continues to be the improved safety of future human spaceflights worldwide."
Columbia broke apart some 200,000 feet over Texas -- just minutes before it was to have touched down in Florida. The shuttle's wing was damaged on takeoff when a large piece of heat-reflecting foam ripped off and gouged a hole in it.
During re-entry, the hole allowed atmospheric gases to burn the wing and destroy the spacecraft. The oldest orbiter in the fleet, Columbia had just completed a 16-day science mission.
Killed were commander Rick Husband, pilot Willie McCool, payload commander Michael Anderson and mission specialists David Brown, Kalpana Chawla, Laurel Clark and Ilan Ramon, an Israeli Air Force colonel who was Israel's first astronaut.
But the report also acknowledged that "the breakup of the crew module ... was not survivable by any currently existing capability."
The NASA report found the astronauts knew for about 40 seconds that they did not have control of the shuttle before they likely were knocked unconscious as Columbia broke apart around them.
The report also found that while crew members were wearing their pressurized suits, one astronaut did not have on a helmet, three were not wearing gloves and none lowered the visors before the module lost cabin pressure. One astronaut also was not seated.
"In this accident, none of those actions would have ultimately made any difference," said former shuttle program manager Wayne Hale, now a deputy NASA administrator.
The graphic, 400-page investigative report relied on video, recovered debris and medical findings, supplemented with computer modeling and analyses. It also includes many recommendations to make space travel safer for future astronauts.
A shuttle-program source told CNN the families of the astronauts who died were brought in specifically to look at the report and even in some cases to help with its preparation. The report took more than five years to complete.
"The members of this team have done an outstanding job under difficult and personal circumstances," said Johnson Space Center director Michael L. Coats. "Their work will ensure that the legacy of Columbia and her heroic crew continues to be the improved safety of future human spaceflights worldwide."
Columbia broke apart some 200,000 feet over Texas -- just minutes before it was to have touched down in Florida. The shuttle's wing was damaged on takeoff when a large piece of heat-reflecting foam ripped off and gouged a hole in it.
During re-entry, the hole allowed atmospheric gases to burn the wing and destroy the spacecraft. The oldest orbiter in the fleet, Columbia had just completed a 16-day science mission.
Killed were commander Rick Husband, pilot Willie McCool, payload commander Michael Anderson and mission specialists David Brown, Kalpana Chawla, Laurel Clark and Ilan Ramon, an Israeli Air Force colonel who was Israel's first astronaut.
luni, 20 iunie 2011
Facebook fraud a 'major issue'
Hacking of Facebook accounts to scam people out of money has become a "major issue" for the social networking site, its head of European public policy, Lord Richard Allan, has told the Guardian.
As a result the site is implementing new ways of detecting when its users' accounts have been hacked, and is adding warnings if it is accessed from unusual locations or by different methods than usual.
Allan said that hacking was a problem that would be countered by sophisticated methods of tracking unusual user behaviour.
"The latest thing you'll see that is a major issue is people hacking into accounts. Now, if you're logging in from an unusual location you'll get extra security questions and if you want to login by a new device [Facebook] notifies you by SMS or email," Allan said, adding that the company's "site integrity" project – which aims to track suspicious activity – is developing new ways to protect its 500 million users.
Ronald K Noble, secretary general of law enforcement agency Interpol, last week revealed that his Facebook identity was recently targeted by individuals seeking access to highly sensitive information on wanted criminals. On the most high-profile case of Facebook identity hacking to date, Noble said: "Just recently Interpol's information security incident response team discovered two Facebook profiles attempting to assume my identity as Interpol's secretary general. One of the impersonators was using this profile to obtain information on fugitives targeted during our recent Operation Infra Red."
Among the new security methods being employed by Facebook are "name verification" – where someone logging on from a new location is shown a number of photos of their friends and is asked to verify their names. Though that is simple for the real user, it is almost impossible for anyone else.
Malicious hacking continues to generate headlines for Facebook, which has 26 million monthly unique users in the UK, despite the company putting in place numerous methods of prevention. In a case recently noted in by the Sunday Times, Abigail Pickett, a British student travelling in Columbia, found that her account had been hacked and was being used to send requests for money to friends on the pretext that she was "stranded" in another country. Facebook told her that the account was in fact being accessed from Nigeria.
A Facebook spokeswoman told the Guardian that the site has "complex automated systems that work behind the scenes to detect and flag Facebook accounts that are likely to be compromised", adding that once "phony" messages are detected then all instances of that message are deleted.
Fraudsters have been hacking into the accounts of Facebook users and duping their friends out of relatively large sums of money, a trick about which the FBI and other authorities had previously raised concerns. The site's international law enforcement efforts are overseen by a former FBI agent who worked on cyber-crime before joining Facebook in 2005.
"It is unfortunate that some people use the internet to maliciously target people either via scams or by compromising accounts on Facebook, over email or on fake websites," the spokeswoman said. "However, unlike other websites, or email, or even the phone, we provide our users with robust reporting tools to report any content they are unsure of and anything which violates our terms, will be removed quickly."
• Facebook has declined to say when its location-sharing service Places will be rolled out to the rest of Europe. Although it was announced in the US last month and launched in the UK last week, Michael Sharon, product manager for Places, would only say: "We are taking it slow to make sure we have a high-quality experience [in all localities]."
The impact of technology on privacy is currently at the fore of public debate in Germany, with calls for regulation intensifying around Google's planned Street View rollout in the country. Despite this, Allan told the Guardian that the privacy settings on Facebook Places will "stay the same across all of our major markets", adding: "We follow all developments on privacy across Europe and we're confident that [Places] suits the requirements of all the major markets we operate in.
"Places is comparable to being able to mention people in status updates. The critical thing to note is that Places is about individual users. Everything is done by the users, nothing is done without the user's knowledge. So while we're sensitive to the privacy debate around Europe we believe our products fit the requirements of the countries we operate in."
Facebook has an ongoing relationship with child safety organisations and NGOs, as well as having a safety advisory board to compose its privacy settings which at one point ran into the hundreds for individual users. Allan said: "We're trusting the common sense of our users and finding [Facebook products] are valuable and useful in everyday lives."
Abonați-vă la:
Postări (Atom)