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Saturday 6 August 2011
Asylum seekers: Australia will not grant exemptions to children
SWAP DEAL: Myanmar refugee Tial Za Eng Sung plays with her children and her young relative (right) in their flat in Kuala Lumpur. Malaysia is poised to receive the first batch of refugees under a swap deal with Australia aimed at helping both sides to tackle a rising influx of refugees. Under the agreement, Malaysia will receive 800 unprocessed asylum seekers from Australia which in return will accept 4,000 refugees whose claims have been approved for resettlement. — Reuters photo
MELBOURNE: The Australian government said it will stick to its plans to ship the latest asylum seeker arrivals to Malaysia, and will not grant exemptions to the large number of minors.
Immigration Minister Chris Bowen said those coming to Australia or who put their children on boats should work on the basis that they would be taken to Malaysia.
“No blanket exemptions. I’ll not have the situation where we provide a reward for people who put their children on a boat and undertake that dangerous journey,” he was quoted by the Australian Associated Press as saying.
The Australian Immigration Department yesterday confirmed there were 18 children among the latest boatload of asylum seekers.
The department said it had checked the ages of all asylum seekers who had claimed to be minors and found one to actually be an adult, bringing the number of children to 18, including 13 who were unaccompanied.
AAP said the high proportion of children on the vessel had been interpreted as a deliberate move by people smugglers to test Canberra’s resolve in implementing its Malaysian solution. — Bernama
Bowen said the government would adopt a case-by-case approach to any particular vulnerabilities among the asylum seekers.
“But I know, sure as night follows day, that if you’ve blanket exemptions people smugglers would exploit that loophole and put children on boats, and we’d be dealing with the dangerous situation of boatloads of children,” he said. — Bernama
Its been two days
Lol. Its been 2 days I haven't log in to The Whisperer. First of all to my readers I'm sorry if there ain't any new post at my blog. I've been busy for all this time. I want to share something to you guys. There's is an Operating Program/System called Linux and one of it is Ubuntu. Ubuntu is as same as Mac Software and Windows 7. Ubuntu is even greater than Windows 7 and has less effected by Viruses. Ubuntu has its own weakness that its has a slow reading on printers. But Ubuntu doesn't need to installs software from Google search because its has its own software center. You can search what you need in Ubuntu Software Center. Ubuntu version 11.04 is the newest and if you want to try it go to http://www.ubuntu.com. If you want Ubuntu you must save all of your important files in other computer because Ubuntu will remove all Windows 7 software and anything in your computer. Be careful if you don't want to lose your files.
Wednesday 3 August 2011
Much ado about Pluto
Recent discoveries of Pluto-like objects in the outer solar system have sparked debate about the nature of the tiniest "planet"
Feb 17, 1999: In 1979 the Solar System became a bit mixed up. That's when Pluto, which travels in a highly elliptical orbit, temporarily moved closer to the sun than Neptune. Every 248 years the two planets swap places and for about 20 years Pluto becomes the eighth planet and Neptune the ninth. This topsy-turvy situation was rectified last Thursday, Feb. 11, when Pluto crossed Neptune's orbit and became the ninth planet once again.
Right: Pluto is the only planet that has not been visited by a spacecraft. Even the Hubble Space Telescope can resolve only the largest features on its surface, shown in this image of one hemisphere. The brightness variations could be due to craters and basins, methane and nitrogen frosts, or even areas of primordial organic matter. No one knows, and the mystery may remain until some future spacecraft pays a visit to this distant planet.
Right: Pluto is the only planet that has not been visited by a spacecraft. Even the Hubble Space Telescope can resolve only the largest features on its surface, shown in this image of one hemisphere. The brightness variations could be due to craters and basins, methane and nitrogen frosts, or even areas of primordial organic matter. No one knows, and the mystery may remain until some future spacecraft pays a visit to this distant planet.
One of these things is not like the others
But is Pluto really a planet? That's what astronomers have been discussing since late last year when some members of the International Astronomical Union suggested that Pluto be given a minor planet designation. Why? For one thing Pluto is very small. It's 6 times smaller than Earth, and even smaller than seven of the solar system's moons (the Moon, Io, Europa, Ganymede, Callisto, Titan and Triton). Pluto's own moon, Charon, is larger in proportion to its planet than any other satellite in the solar system. Some astronomers consider the pair to be a double planet.
December 3: Mars Polar Lander nears touchdown December 2: What next, Leonids? November 30: Polar Lander Mission Overview November 30: Learning how to make a clean sweep in space |
Pluto's composition is unknown, but its density (about 2 gm/cm3) indicates that it is probably a mixture of rock and ice. All the other rocky planets -- Mercury, Venus, Earth and Mars -- are located in the inner solar system, close to the Sun. Except for Pluto, all of the outer planets -- Jupiter, Saturn, Uranus and Neptune -- are gaseous giants. Once again, Pluto is a misfit.
Pluto behind the 8 ball
Despite its well-known peculiarities, Pluto's official status as a planet was never in jeopardy until 1992 when David Jewitt and J. Luu discovered a curious object called 1992 QB1. QB1 is a small icy body, similar in size to an asteroid, orbiting 1.5 times further from the sun than Neptune. QB1 was the first hint that there might be more than just Pluto in the distant reaches of the solar system.
Right: Kuiper Belt object 1995 WY2 observed UT 1995 Nov 18 using the Keck 10 meter telescope by D. Jewitt (University of Hawaii) and J. Luu (University of California, Berkeley). These are the discovery images. Each is a 900 second integration. The images are separated by about 18 minutes, during which time the object moves 1 arc per second. Stationary background galaxies are also evident in this short movie. The apparent magnitude is V = 24.2.
Since then nearly 100 objects like QB1 have been found. They are thought to be similar to Pluto in composition and, like Pluto, many orbit the sun in a 3:2 resonance with Neptune. This swarm of Pluto-like objects beyond Neptune is known as the Kuiper Belt, after Gerard Kuiper, who first proposed that such a belt existed and served as a source of short period comets. Astronomers estimate that there are at least 35,000 Kuiper Belt objects greater than 100 km in diameter, which is several hundred times the number (and mass) of similar sized objects in the main asteroid belt.
Right: Kuiper Belt object 1995 WY2 observed UT 1995 Nov 18 using the Keck 10 meter telescope by D. Jewitt (University of Hawaii) and J. Luu (University of California, Berkeley). These are the discovery images. Each is a 900 second integration. The images are separated by about 18 minutes, during which time the object moves 1 arc per second. Stationary background galaxies are also evident in this short movie. The apparent magnitude is V = 24.2.
Since then nearly 100 objects like QB1 have been found. They are thought to be similar to Pluto in composition and, like Pluto, many orbit the sun in a 3:2 resonance with Neptune. This swarm of Pluto-like objects beyond Neptune is known as the Kuiper Belt, after Gerard Kuiper, who first proposed that such a belt existed and served as a source of short period comets. Astronomers estimate that there are at least 35,000 Kuiper Belt objects greater than 100 km in diameter, which is several hundred times the number (and mass) of similar sized objects in the main asteroid belt.
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Other than its relatively large size, Pluto is practically indistinguishable from the Kuiper Belt objects (KBOs) and short period comets. The main difference is Pluto's reflectivity, which is much higher than that of known KBOs. "Pluto has a higher albedo (60%) than we suspect for the other KBOs," explains Dr. David Jewitt of the University of Hawaii. "But this is an artifact of size - Pluto has enough mass & gravity to retain a tenuous atmosphere from which bright surface frosts may be deposited on the surface."
David Jewitt and his colleagues at the Institute for Astronomy are leaders in the search for new members of the Kuiper Belt. They are presently scanning a 50 sq. degree area of the sky for KBO's using the University of Hawaii's 8192 x 8192 pixel CCD camera, and are experimenting with an even larger 12,000 x 8,000 pixel camera for faster searches. So far their efforts have met with considerable success. They have discovered over 40 KBO's in recent years, some of which are comparable in size to Pluto.
"We've already found objects 1/3rd the diameter of Pluto," says David Jewitt," even though we have examined only a tiny fraction of the sky. An example is 1996 TO66, which is 800 km diameter. It would be incredible in its own right if Pluto proved to be the only 2000 km object. I think we'll have Pluto II, Pluto III....within a few years."
Right: Artist's conception of the Pluto-Kuiper Express, a spacecraft that NASA planners hope will visit Pluto and Charon around 2010. Pluto is the only planet in our Solar System not yet viewed close-up by spacecraft. As a result many basic questions about Pluto remain unanswered. For example, what are the mysterious dark patches revealed in Hubble images of Pluto? Could they be due to photochemical reactions caused by cosmic rays, or perhaps areas of primordial organic matter? Does Charon, like Pluto, have dark spots and an atmosphere? Or is it a very different kind of body? Mission planners hope to answer these questions and many more. Depending on the success of the Pluto-Charon encounter, the space probe could go on to visit objects in the Kuiper Belt.
Nine's a charm
Dr. Jewitt raises the interesting possibility that Kupier Belt objects might one day be discovered that are even larger than our ninth planet. If that happens, what does it mean for Pluto? Should it be stripped of planetary status and reclassified as a member of the Kuiper Belt? Or should newly discovered "Plutos" be classified as planets as well?
Left: A Hubble telescope image of Pluto and its satellite Charon.
These are difficult questions that await the astronomical community. For now, however, Pluto's status as a planet seems secure. In a press release dated Feb. 3, 1999 the International Astronomical Union stated that "No proposal to change the status of Pluto as the ninth planet in the solar system has been made by any Division, Commission or Working Group of the IAU responsible for solar system science. Lately, a substantial number of smaller objects have been discovered in the outer solar system, beyond Neptune, with orbits and possibly other properties similar to those of Pluto. It has been proposed to assign Pluto a number in a technical catalogue or list of such Trans-Neptunian Objects (TNOs) so that observations and computations concerning these objects can be conveniently collated. This process was explicitly designed to not change Pluto's status as a planet."
Mistaken reports that the IAU intended to strip Pluto of its planetary status caused an uproar among astronomers and in the popular press. It seems that Pluto is a sentimental favorite to remain a planet among both scientists and the public. However, if more trans-Neptunian objects are discovered that are even larger than Pluto, the debate could begin anew.
Left: A Hubble telescope image of Pluto and its satellite Charon.
These are difficult questions that await the astronomical community. For now, however, Pluto's status as a planet seems secure. In a press release dated Feb. 3, 1999 the International Astronomical Union stated that "No proposal to change the status of Pluto as the ninth planet in the solar system has been made by any Division, Commission or Working Group of the IAU responsible for solar system science. Lately, a substantial number of smaller objects have been discovered in the outer solar system, beyond Neptune, with orbits and possibly other properties similar to those of Pluto. It has been proposed to assign Pluto a number in a technical catalogue or list of such Trans-Neptunian Objects (TNOs) so that observations and computations concerning these objects can be conveniently collated. This process was explicitly designed to not change Pluto's status as a planet."
Mistaken reports that the IAU intended to strip Pluto of its planetary status caused an uproar among astronomers and in the popular press. It seems that Pluto is a sentimental favorite to remain a planet among both scientists and the public. However, if more trans-Neptunian objects are discovered that are even larger than Pluto, the debate could begin anew.
10th Planet Discovered
Astronomers have found a new planet in the outer reaches of the solar system.
July 29, 2005: "It's definitely bigger than Pluto." So says Dr. Mike Brown of the California Institute of Technology who announced today the discovery of a new planet in the outer solar system.
The planet, which hasn't been officially named yet, was found by Brown and colleagues using the Samuel Oschin Telescope at Palomar Observatory near San Diego. It is currently about 97 times farther from the sun than Earth, or 97 Astronomical Units (AU). For comparison, Pluto is 40 AU from the sun.
Right: An artist's concept of the new planet.
This places the new planet more or less in the Kuiper Belt, a dark realm beyond Neptune where thousands of small icy bodies orbit the sun. The planet appears to be typical of Kuiper Belt objects--only much bigger. Its sheer size in relation to the nine known planets means that it can only be classified as a planet itself, Brown says.
Backyard astronomers with large telescopes can see the new planet. But don't expect to be impressed: It looks like a dim speck of light, visual magnitude 19, moving very slowly against the starry background. "It is currently almost directly overhead in the early-morning eastern sky in the constellation Cetus," notes Brown.
The planet was discovered by, in addition to Brown, Chad Trujillo, of the Gemini Observatory in Mauna Kea, Hawaii, and David Rabinowitz, of Yale University, New Haven, Connecticut. They first photographed the new planet with the 48-inch Samuel Oschin Telescope on October 31, 2003. The object was so far away, however, that its motion was not detected until they reanalyzed the data in January of this year. In the last seven months, the scientists have been studying the planet to better estimate its size and its motions.
"We are 100 percent confident that this is the first object bigger than Pluto ever found in the outer solar system," Brown adds.
Right: The new planet, circled in white, moves across a field of stars on Oct. 21, 2003. The three photos were taken about 90 minutes apart. Image credit: Samuel Oschin Telescope, Palomar Observatory.
Telescopes have not yet revealed the planet's disk. To estimate how big it is, the astronomers must rely on measurements of the planet's brightness. Like all planets, this new one presumably shines by reflecting sunlight. The bigger the planet, generally speaking, the bigger the reflection. The reflectance, the fraction of light that bounces off the planet, is not yet known. Nevertheless, it is possible to set limits on the planet's diameter:
"Even if it reflected 100 percent of the light reaching it, it would still be as big as Pluto," says Brown. Pluto is 1400 miles (2300 km) wide. "I'd say it's probably [about] one and a half times the size of Pluto, but we're not sure."
The planet's temporary name is 2003 UB313. A permanent name has been proposed by the discoverers to the International Astronomical Union, and they are awaiting the decision of this body before announcing the name. Stay tuned!
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