Barack Obama in Kenya

Barack Obama with his grandmother in Kenya

The Stellar Accretion History of the Milky Way Through SEGUE Observations of Halo Substructure

We identify 20 (17 for the first time kinematically cold streams in the inner halo of the Milky Way. Our result is based on the observed spatial and radial velocity distribution of metal-poor main sequence turn-off (MPMSTO) stars in 117 Sloan Extension for Galactic Understanding (SEGUE) lines-of-sight. We show that the observed distribution is consistent with a smooth stellar component of the Milky Way's halo at large scales, but disagrees significantly at the radial velocities that correspond to our detections. We prove that all of our detections are significant to more than 10-sigma and that we expect only one of our detections to be a false-positive. These cold streams represent the observable stellar populations of those dark matter halos that merged to form the Milky Way, and we use our detections and estimates of our completeness to predict that approximately 3000 streams are present in the entire inner halo. We compare our detections with the very high resolution dark matter-only Via Lactea simulation to constrain the mapping of dark matter halos to their stellar content. Finally, we consider the implications of our detections in the context of the formation of Milky Way.

Kevin C. Schlaufman (Astronomy and Astrophysics Department, University of California, Santa Cruz)

Ministry confirms Safir satellite-carrier rocket launch

Ministry of Defense and Armed Forces Logistics said Friday that in presence of President Mahmoud Ahmadinejad, Iran's `Safir' (Messenger) satellite-carrier rocket, carrying Iran's first `Omid' (Hope) Satellite, was successfully launched into the space tentatively on Sunday.

The Ministry statement, a copy of which was made available to IRNA on Sunday, said the launch thus paved the way for placing the first Iranian satellite in orbit.

It said the rocket had been built by Iranian experts and fired tentatively on the auspicious birthday anniversary of Hazrat Mahdi (May God Hasten His Reappearance).

Iran successfully fires rocket carrying its 1st satellite

Joint Chief of Staff on Sunday congratulated Supreme Leader of Islamic Revolution Ayatollah Seyed Ali Khamenei and brave Iranian nation on successful launching of the rocket carrying the country's first satellite.

In a message issued on Sunday, the Joint Chief of Staff said the rocket carrying the country's first satellite, the `Hope' Satellite, was successfully fired on the birth Anniversary of the last Imam of Shiites, Hazrat Mahdi (May God Hasten His Reappearance), thus illustrating the auspicious name of the Imam in the space.

The message said the launching marks the second instance of successful tentative firing of such rockets.

Beijing advocates safe sex during Olympics

To advocate safe sex and AIDS prevention, Beijing's health bureau distributed 400,000 free condoms to 119 contract hotels of the Olympic Games, as well as other hotels in the city, said an official with the bureau on Friday.

Jin Dapeng, the bureau's Party chief, said the condoms had been put in more than 90,000 rooms of 424 hotels rated three stars and above.

The bureau also distributed 250,000 free pamphlets on AIDS prevention and control in contract and other hotels.

He said the authorities had trained thousands of Olympic volunteers to advocate AIDS prevention during the Games.

The Chinese organizers had worked with United Nations Program on HIV/AIDS (UNAIDS) and the International Olympic Committee to distribute information about AIDS to participants in this year's Games.

In the clinic at the Olympic Village, some 100,000 high-quality condoms were available for distribution along with information on HIV prevention in English, French and Chinese.

"Now 180 college students and 500 community volunteers are ready to publicize AIDS-related knowledge. We have opened 40 clinics in Beijing's 18 districts and counties to offer free HIV tests and AIDS counseling," Jin said.

Jin said the Games were a good opportunity to amplify the AIDS prevention message globally as it brought an enormous influx of visitors to Beijing.

Texas district will let teachers carry guns

A tiny Texas school district will allow teachers and staff members to carry concealed firearms to protect against school shootings, provided the gun-toting employees follow certain requirements.

The small community of Harrold in north Texas is a 30-minute drive from the Wilbarger County Sheriff's Office, leaving students and teachers without protection, said David Thweatt, superintendent of the Harrold Independent School District. The lone campus of the 110-student district sits near a heavily traveled highway, which could make it a target, he argued.

"When the federal government started making schools gun-free zones, that's when all of these shootings started. Why would you put it out there that a group of people can't defend themselves? That's like saying 'sic 'em' to a dog," Thweatt said in a story published Friday on the Fort Worth Star-Telegram's Web site.

Barbara Williams, a spokeswoman for the Texas Association of School Boards, said her organization did not know of another district with such a policy. Ken Trump, a Cleveland, Ohio-based school security expert who advises districts nationwide, said Harrold is the first district with such a policy.

Trustees approved the policy change last year, and it takes effect when classes begin this month. For employees to carry a pistol, they must have a Texas license to carry a concealed handgun, must be authorized to carry by the district, must receive training in crisis management and hostile situations and must use ammunition designed to minimize the risk of ricocheting bullets.

Officials researched the policy and considered other options for about a year before approving the policy change, Thweatt said. The district also has other measures in place to prevent a school shooting, he said.

"The naysayers think [a shooting] won't happen here. If something were to happen here, I'd much rather be calling a parent to tell them that their child is OK because we were able to protect them," Thweatt said.

Texas law outlaws firearms at schools unless specific institutions allow them.

It isn't clear how many of the 50 or so teachers and staff members will be armed this fall, because Thweatt did not disclose that information, to keep it from students or potential attackers.

Military wants to study mind-reading

Here's a mind-bending idea: The U.S. military is paying scientists to study ways to read people's thoughts.

The hope is that the research could someday lead to a gadget capable of translating the thoughts of soldiers who suffered brain injuries in combat or even stroke patients in hospitals. But the research also raises concerns that such mind-reading technology could be used to interrogate the enemy.

Armed with a $4 million grant from the Army, scientists are studying brain signals to try to decipher what a person is thinking and to whom the person wants to direct the message.

The project is a collaboration among researchers at the University of California, Irvine; Carnegie Mellon University; and the University of Maryland.

The scientists use brain wave-reading technology known as electroencephalography, or EEG, which measures the brain's electrical activity through electrodes placed on the scalp.

It works like this: Volunteers wear an electrode cap and are asked to think of a word chosen by the researchers, who then analyze the brain activity.

In the future, scientists hope to develop thought-recognition software that would allow a computer to speak or type out a person's thought.

"To have a person think in a free manner and then figure out what that is, we're years away from that," said lead researcher Michael D'Zmura, who heads UC Irvine's cognitive sciences department.

D'Zmura said such a system would require extensive training by people trying to send a message and dismisses the notion that thoughts can be forced out.

"This will never be used in a way without somebody's real, active cooperation," he said.

John Pike, director of GlobalSecurity.org, a Virginia-based defense research firm, said the technology is still too nascent to be of practical use for the military.

"They're still in the proof of principle stage," Pike said.

A message left with the Army was not immediately returned Friday.