English conversation 1
By Jonathan Amos
Science reporter, BBC News
Science reporter, BBC News
A colossal new ring has been identified around Saturn.
The dusty hoop lies some 13 million km (eight million miles) from the planet, about 50 times more distant than the other rings and in a different plane.
Scientists tell the journal Nature that the tenuous ring is probably made up of debris kicked off Saturn's moon Phoebe by small impacts.
They think this dust then migrates towards the planet where it is picked up by another Saturnian moon, Iapetus.
 |   The particles smack Iapetus like bugs on a windshield  Dr Anne Verbiscer, University of Virginia |
The discovery would appear to resolve a longstanding mystery in planetary science: why the walnut-shaped Iapetus has a two-tone complexion, with one side of the moon significantly darker than the other.
"It has essentially a head-on collision. The particles smack Iapetus like bugs on a windshield," said Anne Verbiscer from the University of Virginia, US.
Observations of the material coating the dark face of Iapetus indicate it has a similar composition to the surface material on Phoebe.
The scale of the new ring feature is astonishing. Nothing like it has been seen elsewhere in the Solar System.
The more easily visible outlier in Saturn's famous bands of ice and dust is its E-ring, which encompasses the orbit of the moon Enceladus. This circles the planet at a distance of just 240,000km.
The newly identified torus is not only much broader and further out, it is also tilted at an angle of 27 degrees to the plane on which the more traditional rings sit.
This in itself strongly links the ring's origin to Phoebe, which also takes a highly inclined path around Saturn.
Scientists suspected the ring might be present and had the perfect tool in the Spitzer space telescope to confirm it.
The US space agency observatory is well suited to picking up the infrared signal expected from cold grains of dust about 10 microns (millionths of a metre) in size.
|  Impacts on the moon Phoebe are probably supplying the ring  |
The ring would probably have a range of particle sizes - some bigger than this, and some smaller.
Modelling indicates the pressure of sunlight would push the smallest of these grains towards the orbit of Iapetus, which is circling Saturn at a distance of 3.5 million km.
"The particles are very, very tiny, so the ring is very, very tenuous; and actually if you were standing in the ring itself, you wouldn't even know it," Dr Verbiscer told BBC News.
"In a cubic km of space, there are all of 10-20 particles."
Indeed, so feeble is the ring that scientists have calculated that if all the material were gathered up, it would fill a crater on Phoebe no more than a kilometre across.
The moon is certainly a credible source for the dust. It is heavily pockmarked. It is clear that throughout its history, Phoebe has been hit many, many times by space rocks and clumps of ice.
![[insert caption here]](http://www.voanews.com/khmer/images/090303-cambodian-police-225.jpg) |
| Original report from Washington 06 October 2009 |
Cambodian police working with the US Federal Bureau of Investigation arrested seven people and seized 16 kilograms of heroin, following three months of investigation, officials said Monday. Police also found counterfeit US dollars in the Oct. 2 raid.
“In the operation, we did an investigation and tracked [the suspects] down for almost three months, with the support of the FBI representative in Cambodia,” said Chhay Sinarith, chief of the Interior Ministry’s security department.
Suspects were arrested in Phnom Penh and Stung Treng province. The raid included the arrest of Lam Sokha, a suspected trafficker who has been arrested and released in recent years, police and court officials said.
The seven suspects were sent to Phnom Penh Municipal Court on Monday and would be questioned by prosecutors this week, officials said.
Police said the heroin moved through neighboring countries through Stung Treng, which borders Laos.
The discovery of heroin, crystal methamphetamine, or “ice,” drug production and counterfeit money made the raid a major case, Chhay Sinarith said.
The US State Department praised Cambodia for its anti-drug efforts in 2009, but said the country faces increasing problems of consumption, trafficking and the production of dangerous drugs.
The State Department warned that crackdowns on trafficking in Thailand and China had made Cambodia an attractive route for traffickers, while internally, use of amphetamines, including ice, was escalating.
| 07 October 2009 |
U.S. President Barack Obama says he will not reduce U.S. troops in Afghanistan and focus solely on counterterrorism.
Administration officials say President Obama made the comment to congressional leaders Tuesday, during a 90-minute White House meeting on Afghanistan. Mr. Obama meets with senior military and political advisors for a strategy session on Pakistan and Afghanistan Wednesday, eight years after the war started.
(L-R), House Maj. Leader Hoyer, Sen. McCain, Senate Min. Leader McConnell , House Minority Leader Boehner at the White House, 06 Oct 2009
A senior administration official said the president assured the bipartisan group of lawmakers the policy review will be rigorous and deliberate, and move forward with a sense of urgency.
The U.S. commander in Afghanistan, Army General Stanley McChrystal, has warned the U.S. could lose the conflict if more troops are not deployed to Afghanistan. He is expected to ask for as many as 40,000 additional troops.
Mr. Obama is said to be leaning toward a more modest buildup of U.S. military forces. Republican Senator John McCain told reporters after the meeting that he worries the president will employ "half-measures" in prosecuting the war.
McCain said defeating the Taliban is essential to the goal of eliminating the al-Qaida terrorist network.
Senate Minority Leader Mitch McConnell and other Republican lawmakers are urging Mr. Obama to heed the recommendations of his military commanders.
But many of Mr. Obama's fellow Democrats oppose deploying more U.S. forces. The speaker of the House of Representatives, Nancy Pelosi, told reporters that many issues need to be addressed before the president decides how to proceed.
But Senate Majority Leader Harry Reid, a Democrat, said lawmakers assured Mr. Obama they would support him, regardless of his decision.
U.S. casualties in Afghanistan have risen sharply in recent months, as forces pursue more aggressive operations against the Taliban and other militant groups.
Recent public opinion polls have shown support for the war is steadily declining. White House spokesman Robert Gibbs said Tuesday politics will not play a role in Mr. Obama's final decision.
Happy Khmer New Year 2009!!-RMH Vol.146#10
Happy Khmer New Year 2009!!-SD vol.81#8
