Monday, June 24, 2013
The Majesty Of Space
Bright Young Supernova
While performing an extensive X-ray survey of our galaxy's central regions, NASA's Swift satellite has uncovered the previously unknown remains of a shattered star. Designated G306.3–0.9 after the coordinates of its sky position, the new object ranks among the youngest-known supernova remnants in our Milky Way galaxy.
"Astronomers have previously cataloged more than 300 supernova remnants in the galaxy," said lead scientist Mark Reynolds, a postdoctoral researcher at the University of Michigan in Ann Arbor. "Our analysis indicates that G306.3–0.9 is likely less than 2,500 years old, making it one of the 20 youngest remnants identified."
Astronomers estimate that a supernova explosion occurs once or twice a century in the Milky Way. The expanding blast wave and hot stellar debris slowly dissipate over hundreds of thousands of years, eventually mixing with and becoming indistinguishable from interstellar gas.
Like fresh evidence at a crime scene, young supernova remnants give astronomers the best opportunity for understanding the nature of the original star and the details of its demise. Supernova remnants emit energy across the electromagnetic spectrum, from radio to gamma rays, and important clues can be found in each energy band. X-ray observations figure prominently in revealing the motion of the expanding debris, its chemical content, and its interaction with the interstellar environment, but supernova remnants fade out in X-ray light after 10,000 years. Indeed, only half of those known in the Milky Way galaxy have been detected in X-rays at all.
Reynolds leads the Swift Galactic Plane Survey, a project to image a two-degree-wide strip along the Milky Way’s central plane at X-ray and ultraviolet energies at the same time. Imaging began in 2011 and is expected to complete this summer. "The Swift survey leverages infrared imaging previously compiled by NASA’s Spitzer Space Telescope and extends it into higher energies," said team member Michael Siegel, a research associate at the Swift Mission Operations Center (MOC) in State College, Pa., which is operated by Penn State University. "The infrared and X-ray surveys complement each other because light at these energies penetrates dust clouds in the galactic plane, while the ultraviolet is largely extinguished."
On Feb. 22, 2011, Swift imaged a survey field near the southern border of the constellation Centaurus. Although nothing unusual appeared in the ultraviolet exposure, the X-ray image revealed an extended, semi-circular source reminiscent of a supernova remnant. A search of archival data revealed counterparts in Spitzer infrared imagery and in radio data from the Molonglo Observatory Synthesis Telescope in Australia. To further investigate the object, the team followed up with an 83-minute exposure using NASA’s Chandra X-ray Observatory and additional radio observations from the Australia Telescope Compact Array (ATCA), located near the town of Narrabri in New South Wales.
"The fantastic sensitivity of ATCA has enabled us to image what, at radio wavelengths, turns out to be the dimmest remnant we have ever seen in our galaxy," said team member Cleo Loi, an undergraduate student at the University of Sydney who led the analysis of the radio observations.
Using an estimated distance of 26,000 light-years for G306.3–0.9, the scientists determined that the explosion’s shock wave is racing through space at about 1.5 million mph (2.4 million km/h). The Chandra observations reveal the presence of iron, neon, silicon and sulfur at temperatures exceeding 50 million degrees F (28 million C), a reminder not only of the energies involved but of the role supernovae play in seeding the galaxy with heavy elements produced in the hearts of massive stars. "We don’t yet have enough information to determine what type of supernova this was and therefore what type of star exploded, but we’ve planned a further Chandra observation to improve the picture,” said coauthor Jamie Kennea, also a researcher at the Swift MOC. "We see no compelling evidence that the explosion formed a neutron star, and this is something we hope can be determined one way or the other by future work."
Image: Credit: X-ray: NASA/CXC/Univ. of Michigan/M. Reynolds et al; Infrared: NASA/JPL-Caltech; Radio: CSIRO/ATNF/ATCA [high-resolution]
Caption: NASA
While performing an extensive X-ray survey of our galaxy's central regions, NASA's Swift satellite has uncovered the previously unknown remains of a shattered star. Designated G306.3–0.9 after the coordinates of its sky position, the new object ranks among the youngest-known supernova remnants in our Milky Way galaxy.
"Astronomers have previously cataloged more than 300 supernova remnants in the galaxy," said lead scientist Mark Reynolds, a postdoctoral researcher at the University of Michigan in Ann Arbor. "Our analysis indicates that G306.3–0.9 is likely less than 2,500 years old, making it one of the 20 youngest remnants identified."
Astronomers estimate that a supernova explosion occurs once or twice a century in the Milky Way. The expanding blast wave and hot stellar debris slowly dissipate over hundreds of thousands of years, eventually mixing with and becoming indistinguishable from interstellar gas.
Like fresh evidence at a crime scene, young supernova remnants give astronomers the best opportunity for understanding the nature of the original star and the details of its demise. Supernova remnants emit energy across the electromagnetic spectrum, from radio to gamma rays, and important clues can be found in each energy band. X-ray observations figure prominently in revealing the motion of the expanding debris, its chemical content, and its interaction with the interstellar environment, but supernova remnants fade out in X-ray light after 10,000 years. Indeed, only half of those known in the Milky Way galaxy have been detected in X-rays at all.
Reynolds leads the Swift Galactic Plane Survey, a project to image a two-degree-wide strip along the Milky Way’s central plane at X-ray and ultraviolet energies at the same time. Imaging began in 2011 and is expected to complete this summer. "The Swift survey leverages infrared imaging previously compiled by NASA’s Spitzer Space Telescope and extends it into higher energies," said team member Michael Siegel, a research associate at the Swift Mission Operations Center (MOC) in State College, Pa., which is operated by Penn State University. "The infrared and X-ray surveys complement each other because light at these energies penetrates dust clouds in the galactic plane, while the ultraviolet is largely extinguished."
On Feb. 22, 2011, Swift imaged a survey field near the southern border of the constellation Centaurus. Although nothing unusual appeared in the ultraviolet exposure, the X-ray image revealed an extended, semi-circular source reminiscent of a supernova remnant. A search of archival data revealed counterparts in Spitzer infrared imagery and in radio data from the Molonglo Observatory Synthesis Telescope in Australia. To further investigate the object, the team followed up with an 83-minute exposure using NASA’s Chandra X-ray Observatory and additional radio observations from the Australia Telescope Compact Array (ATCA), located near the town of Narrabri in New South Wales.
"The fantastic sensitivity of ATCA has enabled us to image what, at radio wavelengths, turns out to be the dimmest remnant we have ever seen in our galaxy," said team member Cleo Loi, an undergraduate student at the University of Sydney who led the analysis of the radio observations.
Using an estimated distance of 26,000 light-years for G306.3–0.9, the scientists determined that the explosion’s shock wave is racing through space at about 1.5 million mph (2.4 million km/h). The Chandra observations reveal the presence of iron, neon, silicon and sulfur at temperatures exceeding 50 million degrees F (28 million C), a reminder not only of the energies involved but of the role supernovae play in seeding the galaxy with heavy elements produced in the hearts of massive stars. "We don’t yet have enough information to determine what type of supernova this was and therefore what type of star exploded, but we’ve planned a further Chandra observation to improve the picture,” said coauthor Jamie Kennea, also a researcher at the Swift MOC. "We see no compelling evidence that the explosion formed a neutron star, and this is something we hope can be determined one way or the other by future work."
Image: Credit: X-ray: NASA/CXC/Univ. of Michigan/M. Reynolds et al; Infrared: NASA/JPL-Caltech; Radio: CSIRO/ATNF/ATCA [high-resolution]
Caption: NASA
Sunday, June 23, 2013
Blogs With Rule 5 Links
These Blogs Provide Links To Rule 5 Sites:
The Daley Gator has:
Your Sunday Night Salute to Great Blogs and Hooters Girls
The Woodsterman has:
The Woodsterman has:
Rule 5 Woodsterman Style
The Conservative Hideout 2.0 has:
Sunday Links:
The Classic Liberal has:
The Conservative Hideout 2.0 has:
Sunday Links:
The Classic Liberal has:
DID I MISS YOUR RULE 5 LINK AROUND?
EMAIL YOUR LINK AROUND TO: 90NINETYMILES THIS WOULD BE AT GMAIL.
PROGRESSIVES WILL NEVER BE ABLE TO FIGURE THIS OUT.
Hooters Girls of Orange County
The first Hooters opened October 4, 1983, in Clearwater, Florida.
I was working weekends at a hardware store called Scotty's to support my College habit. I delivered the lumber for the first Hooters I ever saw or heard of in my Florida City....
See Them Here:
Hooters Girls of Orange County
I was working weekends at a hardware store called Scotty's to support my College habit. I delivered the lumber for the first Hooters I ever saw or heard of in my Florida City....
Hooters Girls of Orange County
NSA controversy boosts interest in ‘private’ Internet search engines like DuckDuckGo
While Google’s market share has not seen a noticeable dent, privacy search engines like US-based DuckDuckGo and European-based Ixquick have seen jumps in traffic from users seeking to limit their online tracks.
“I think people are seeking out privacy alternatives,” said Gabriel Weinberg, founder of DuckDuckGo, an engine created in 2007, which does not store IP addresses or create profiles of users.
The stored data has become a concern following revelations of a massive surveillance program run by the secretive National Security Agency, with access to data from Google, Yahoo! and other Internet firms.
US officials say the information gathered is vital in the fight against global terrorism.
The same data and profiles can be used by the search engine to deliver ads and sold to outside marketers as well.
“What people type in their search engines is their most personal things,” Weinberg said. “It’s a little creepy that a search engine can know so much about you.”
DuckDuckGo had been growing slowly in recent years, but its traffic charts showed a surge after the first news broke June 6 of the government’s PRISM surveillance program. By June 20, traffic had hit nearly three million queries, double the level of a year earlier.
More than half of DuckDuckGo traffic comes from outside the United States, Weinberg said.
“This NSA story played into the trend of people’s fears” about online tracking, said Weinberg.
Weinberg said another factor is that Google results are being gamed by search engine spammers and other companies trying to rank their results higher.”
Dutch-based Ixquick, which also uses the name StartPage, said it too has seen a dramatic jump in usage after news of the PRISM data sharing program.
Last week, the two meta-search engines — which use the results of Google and other search sites and strip out identifying information — served as many as 3.6 million queries.
“This growth has been sustained, it shows no signs of slowing down,” said spokeswoman Katherine Albrecht.
The revelations about PRISM “really have woken people up,” she said.
“People had heard the message of privacy but hadn’t been able to nail it down to how it relates to them.”
The company proclaims it “has never turned over user data to any government entity anywhere on earth” and is “not directly subject to US jurisdiction.”
Another search engine, California-based Blekko, allows users to select privacy settings and keeps no data if the user selects “do not track.”
“Even if you are not a criminal, you probably make searches that you don’t want your minister, boss, or spouse to know about,” said Blekko’s Greg Lindahl.
Weinberg said DuckDuckGo’s model allows it to make money through “keyword” advertising, without stored profiles. So if someone is searching for a “mortgage,” they might see ads for banks.
This differs from search engines that track the pages people visit and then deliver related ads, a practice known as “retargeting.”
“Retargeting is effective only for a small amount of people, the rest are just annoyed by it,” he said.
Danny Sullivan, editor in chief at the specialized website Search Engine Land, said these kinds of search engines were “interesting” but unlikely to have a major market impact.
“It’s extremely unlikely in the next three to five years that any player will come along and take a sizeable share away from Google,” he said.
A survey of the US market by the research firm comScore showed Google with a 66.5 percent market share, with 13.3 billion search queries in a month, followed by Microsoft (17.3 percent, 3.5 billion) and Yahoo! (12 percent, 2.4 billion).
Sullivan said the news over NSA surveillance “so far doesn’t seem to be spooking” the public.
He said Google does not force people to create a profile that can be used to connect with its other services.
“You can go to Google, and you can do a search without being logged in, and you still get very good results,” Sullivan said.
“If you do log in and connect to these services, Google blows DuckDuckGo out of the water. When it has access to your calendar and search history, Google can predict your answers before you even ask them.”
www.rawstory.com/rs/2013/06/22/nsa-controversy-boosts-interest-in-private-internet-search-engines/
Buzz Aldrin calls for humans to colonise the Red Planet
By Theo LeggettBusiness reporter, BBC News
Buzz Aldrin was the second person to walk on the Moon in 1969On 20 July 1969, when Neil Armstrong and Buzz Aldrin first set foot on the surface of the Moon, it appeared as though mankind was on the verge of a new age of space exploration. After all, if the moon could be conquered, what could prevent us travelling to other planets, even to other solar systems?
It's in human nature to explore, to find a location to begin a settlement. And it is in reach”
Nearly half a century later, the dreams that once seemed so tangible now look more remote than ever. The last man to walk on the Moon was Eugene Cernan, who made the long trip home in December 1972. Since then, humans have been content to orbit the earth, in the realms occupied by satellites and the International Space Station. But we have never again broken free.
Now, one of the original lunar pioneers believes the time has come to make another great leap for mankind. Buzz Aldrin thinks that manned missions to Mars should take place sooner rather than later - within the next quarter of a century. And we shouldn't stop there. He thinks we should begin planning a permanent colony on the Red Planet.
Buzz Aldrin was the second person to walk on the Moon in 1969On 20 July 1969, when Neil Armstrong and Buzz Aldrin first set foot on the surface of the Moon, it appeared as though mankind was on the verge of a new age of space exploration. After all, if the moon could be conquered, what could prevent us travelling to other planets, even to other solar systems?It's in human nature to explore, to find a location to begin a settlement. And it is in reach”
Nearly half a century later, the dreams that once seemed so tangible now look more remote than ever. The last man to walk on the Moon was Eugene Cernan, who made the long trip home in December 1972. Since then, humans have been content to orbit the earth, in the realms occupied by satellites and the International Space Station. But we have never again broken free.
Now, one of the original lunar pioneers believes the time has come to make another great leap for mankind. Buzz Aldrin thinks that manned missions to Mars should take place sooner rather than later - within the next quarter of a century. And we shouldn't stop there. He thinks we should begin planning a permanent colony on the Red Planet.
I caught up with him on a visit to the Paris Air Show, where he has been publicising his new book, "Mission to Mars: My Vision for Space Exploration". A relatively sprightly 83-year-old, he has a reputation for tetchiness - and he certainly dealt rather brusquely with onlookers' requests for autographs. But when I asked him about Mars, he became engaging and animated, showing a boyish enthusiasm for the subject.So why does he think we should be sending astronauts to the red planet?
"Why did the the pilgrims on the Mayflower set out to open up the New World?" he asks.
Colleagues at Nasa's Jet Propulsion Lab celebrate the Mars Curiosity Rover's successful landing in 2012
"Because it's in human nature to explore, to find a location to begin a settlement. And it is in reach."
The simple answer then, appears to be "because it's there". But there is also a more pragmatic reason. He believes that efforts to explore the surface of Mars to date have taken far too long, because the current generation of Mars rovers have to be controlled remotely from Earth - and it takes about 20 minutes for radio signals to be passed each way."One programme manager, who was in charge of doing that with two robots for five years has said we could have accomplished just as much in a single week, if we had had human intelligence controlling them from nearby - from an orbit around Mars itself", he says.
But a mission to Mars would have to overcome huge technological challenges, and would certainly be phenomenally expensive. So who would pay for it all?
"The nation that decides that it is worth doing," he says, "and I believe that is the United States. The United States will commit to doing that."
Yet, at the moment governments around the world are attempting to cut back their spending, and Washington is no exception. In the current climate, it seems almost inconceivable that a government could commit untold billions to fund interplanetary exploration.The Mars Curiosity Rover has been taking images of the planet since August 2012
On the other hand, private firms are showing an interest - companies such as Mars One, a not-for-profit Dutch foundation, which says it plans to establish a colony on Mars by 2023. It wants to use technology developed by the American firm Space X, a business fronted by the maverick entrepreneur Elon Musk.Mr Aldrin points to these firms as evidence that there is enthusiasm for exploring Mars - yet he still believes that governments will have to lead the way.
"Private enterprise usually enters into activities seeking a return on investment," he says.
"That's why we didn't go to the moon in the '60s and '70s just relying on private investment. It was a national investment is science, in development and to assist in the commercialisation of space."
In other words, the commercial benefits may be there - but the rewards are too uncertain to attract enough private backing.
"Why did the the pilgrims on the Mayflower set out to open up the New World?" he asks.
Colleagues at Nasa's Jet Propulsion Lab celebrate the Mars Curiosity Rover's successful landing in 2012"Because it's in human nature to explore, to find a location to begin a settlement. And it is in reach."
The simple answer then, appears to be "because it's there". But there is also a more pragmatic reason. He believes that efforts to explore the surface of Mars to date have taken far too long, because the current generation of Mars rovers have to be controlled remotely from Earth - and it takes about 20 minutes for radio signals to be passed each way."One programme manager, who was in charge of doing that with two robots for five years has said we could have accomplished just as much in a single week, if we had had human intelligence controlling them from nearby - from an orbit around Mars itself", he says.
But a mission to Mars would have to overcome huge technological challenges, and would certainly be phenomenally expensive. So who would pay for it all?
"The nation that decides that it is worth doing," he says, "and I believe that is the United States. The United States will commit to doing that."
Yet, at the moment governments around the world are attempting to cut back their spending, and Washington is no exception. In the current climate, it seems almost inconceivable that a government could commit untold billions to fund interplanetary exploration.The Mars Curiosity Rover has been taking images of the planet since August 2012
On the other hand, private firms are showing an interest - companies such as Mars One, a not-for-profit Dutch foundation, which says it plans to establish a colony on Mars by 2023. It wants to use technology developed by the American firm Space X, a business fronted by the maverick entrepreneur Elon Musk.Mr Aldrin points to these firms as evidence that there is enthusiasm for exploring Mars - yet he still believes that governments will have to lead the way.
"Private enterprise usually enters into activities seeking a return on investment," he says.
"That's why we didn't go to the moon in the '60s and '70s just relying on private investment. It was a national investment is science, in development and to assist in the commercialisation of space."
In other words, the commercial benefits may be there - but the rewards are too uncertain to attract enough private backing.
Buzz Aldrin believes we should colonise Mars over the next 25 yearsMr Aldrin's vision involves astronauts being trained on the Moon for a life on Mars, and ultimately for new colonists to be brought to the new settlement on a routine basis. He thinks this could be done using "interplanetary cyclers", spacecraft that are permanently moving between Mars and Earth.
But such a plan needs willing volunteers, who must be prepared to travel across space with little prospect of ever returning home. A return journey may in fact become physically impossible after much time spent in the weaker gravity of Mars.
Yet he thinks there will be no shortage of volunteers, and the response to the Mars One initiative suggests he is right. Since announcing its plans in April, it has received tens of thousands of applications from would-be Martian explorers."I think that the people who go there will be remembered in history as pioneers," he says, "and the world leader who makes a commitment to establishing a permanent presence on another planet will also be remembered in history as a pioneer."
In fact, as befits one of the very few men ever to have set foot on another world, "pioneer" seems to be Buzz Aldrin's favourite word. It's a term that has rather fallen out of fashion on our well-mapped planet.
But he believes the time has come time to broaden our horizons - and rediscover once again the spirit of exploration.
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