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Dwarf star found orbiting closest to black hole

Researchers have found evidence of a white dwarf star orbiting a likely black hole at a distance of only 961,000 km at an astonishing speed

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star orbiting black hole, wikimedia

New York, March 14, 2017: Researchers have found evidence of a white dwarf star orbiting a likely black hole at a distance of only 961,000 km — just about 2.5 times the distance between the Earth and the Moon.

In a tightest orbital dance ever witnessed for a black hole and a companion star, the star whips around the black hole at an astonishing speed — about two orbits an hour, said the study published in the journal Monthly Notices of the Royal Astronomical Society.

“This white dwarf is so close to the black hole that material is being pulled away from the star and dumped onto a disk of matter around the black hole before falling in,” said study lead author Arash Bahramian, affiliated with the University of Alberta in Canada and Michigan State University in the US.

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“Luckily for this star, we don’t think it will follow this path into oblivion, but instead will stay in orbit,” Bahramian said.

Although the white dwarf does not appear to be in danger of falling in or being torn apart by the black hole, its fate is uncertain.

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The stellar system, known as X9, is located in the globular cluster 47 Tucanae, a dense cluster of stars in our galaxy about 14,800 light years away from the Earth.

“For a long time astronomers thought that black holes were rare or totally absent in globular star clusters,” study co-author Jay Strader from Michigan State University said.

“This discovery is additional evidence that, rather than being one of the worst places to look for black holes, globular clusters might be one of the best,” Strader added.

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For the study, the researchers used data from the Australia Telescope Compact Array as well as NASA’s Chandra X-ray Observatory and NuSTAR telescope. (IANS)

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Astronomers Discover New ‘Mid-size’ Black Hole 100,000 Times More Massive than the Sun

Scientists predict that nearly 100 million of these small black holes should exist in the Milky Way, however only about 60 have been found till now

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Black hole in milky way
A near-infrared image of a black hole at the center of the Milky Way galaxy as seen with Hubble Space Telescope/NICMOS. (NASA/STScI) (VOA)
  • Researches in Japan have discovered a super-massive black hole in Milky Way Galaxy
  • The black hole is believed to weigh as much as 400 suns
  • According to studies,  at least 100 million of these small black holes should exist in the Milky Way

Japan, September 5, 2017 : Astronomers have found new evidence for the existence of a mid-sized black hole, considered the missing link in the evolution of super-massive black holes.

Astronomers in Japan found the possible black hole in our own Milky Way galaxy, a long-theorized object which is bigger than the small black holes formed from a single star, but still much smaller than giant black holes such as the one at the center of the Milky Way.

Black holes are difficult to find because they do not emit any light. However, scientists can detect them by their influence on nearby objects.

The astronomers in Japan found new evidence of the so-called intermediate-mass black hole when they turned a powerful telescope in Chile’s Atacama desert on a gas cloud near the center of the Milky Way. The gases in the cloud move at unusual speeds, and the scientists believed they were being pulled by immense gravitational forces. They say the gravitational force is likely caused by a black hole measuring about 1.4 trillion kilometers across.

black hole in Milky way galaxy
Radio telescope antennas of the ALMA (Atacama Large Millimeter/submillimeter Array) project are seen in the Atacama desert, some 1500 km north of Santiago, Chile, VOA

The findings are published in the journal Nature Astronomy.

Theoretical studies predict at least 100 million of these small black holes should exist in the Milky Way, however only about 60 have been found.

The possible mid-sized black hole is much smaller than the super massive black hole that is located in the center of the galaxy, known as Sagittarius A, which weighs as much as 400 million suns.

“This is the first detection of an intermediate-mass black hole candidate in the Milky Way galaxy,” said the study’s leader, Tomoharu Oka from Keio University, Japan.

If confirmed, the intermediate-mass black hole could help explain how supermassive black holes operate. One theory is that supermassive black holes, which are at the center of most massive galaxies, are formed when smaller black holes steadily coalesce into larger ones. However, until now no definitive evidence has existed for intermediate-mass black holes that could indicate a middle step between the small and massive black holes already detected.

Researchers say they will continue to study the intermediate-mass black hole candidate in the hope of confirming its existence. (VOA)

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Landmark Achievement: 6 Astronomers from India Discover Giant Radio Galaxies (GRGs)

A team of 6 astronomers from India have reportedly discovered Giant Radio Galaxies (GRGs) which are the largest known galaxies in the universe

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Giant Radio Galaxies
Out of total known galaxies, only 300 have been classifies as Giant Radio Galaxies. Wikimedia
  • Six astronomers from India have recently discovered the largest galaxies known to the universe, called Giant Radio Galaxies (GRGs)
  • Only 300 out of total number of galaxies are classified as Giang Radio Galaxies
  • The research was successful taking into account the research of last 6 decades of radio astronomy

July 06, 2017: A team of six astronomers from India has made a landmark discovery. Using the research from last six decades of radio astronomy and a 20-year-old survey, the team has detected the existence of Giant Radio Galaxies (GRGs).

Giant Radio Galaxies are known to be the largest galaxies in the universe. The reason for their large size is unknown as of now. As one of the lead researcher, Pratik Dabhade from Inter-University Centre for Astronomy and Astrophysics (IUCAA), explains in the study, “The huge size of GRGs has defied any theoretical explanation so far. Our work will help in understanding how these galaxies grow to be so large.”

The other researchers also involved include Joydeep Bagchi (IUCAA), Mamta Pommier (CNRS Observatoire de Lyon), Madhuri Gaikwad (Max Planck Institute Bonn), Shishir Sankhyayan (IISER Pune) and Somak Raychaudhary (IUCAA).

Also Read: “Do not Stand and Drink Water”: Here is Why it is often said so

Their research has been published in Journal Monthly Notices of the Royal Astronomical Society. The Giant Radio Galaxies are found co-existing with a supermassive black hole at the core of center of the nucleus. High energy particles are discharged at the speed of light which emerges into two giant radio lobes.

The Giant Radio Galaxies are known to be the last stage of evolution of galaxies, mainly because of their massive size. However, these galaxies are visible only through radio telescopes.

– by Saksham Narula of NewsGram. Twitter: @Saksham2394

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Can Flourishing Islamic State (ISIS) be Stopped in Afghanistan?

The truth about IS and Afghanistan is definitely no picnic

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Taliban fighters react to a speech by their senior leader in the Shindand district of Herat province, Afghanistan, May 27, 2016.
Taliban fighters react to a speech by their senior leader in the Shindand district of Herat province, Afghanistan, May 27, 2016. The rise of IS in Afghanistan has become such a priority that U.S. and Afghan forces sometimes support the Taliban while battling IS, VOA
  • Depending on the location, the proliferation of IS has drawn varied resistance from the Afghan military, U.S. air support and ground troops, local militias, Taliban forces and other militant groups
  • Afghan army planes on Wednesday night accidentally air dropped vital supplies of food and water to IS militants in the Darzab district of northern Jouzjan province instead of to their own besieged troops
  • In the Tora Bora area, where IS has made a strong stand in recent days, local villagers and militias joined with Taliban to rout IS

June 25, 2017: The Islamic State group is rapidly expanding in parts of Afghanistan, advancing militarily into areas where it once had a weak presence and strengthening its forces in core regions, according to Afghan and U.S. officials.

Depending on the location, the proliferation of IS has drawn varied resistance from the Afghan military, U.S. air support and ground troops, local militias, Taliban forces and other militant groups.

Attacking IS has become such a priority in the country, that disparate forces sometimes join together in the ad-hoc fight, with Afghan and U.S. forces finding themselves inadvertently supporting the enemy Taliban in battling IS.

Confusion leads to mistakes

All too often, officials say, mistakes are made due to confusion on the ground.

Afghan army planes on Wednesday night accidentally air dropped vital supplies of food and water to IS militants in the Darzab district of northern Jouzjan province instead of to their own besieged troops, provincial police chief, Rahmatullah Turkistani told VOA. The supplies were meant to help Afghan forces that are countering twin attacks by IS and Taliban militants but were used instead by IS.

“It’s not getting better in Afghanistan in terms of IS,” U.S. Chief Pentagon Spokeswoman Dana White told VOA this week. “We have a problem, and we have to defeat them and we have to be focused on that problem.”

Reinforcements for the IS cause reportedly are streaming into isolated areas of the country from far and wide. There are reports of fighters from varied nationalities joining the ranks, including militants from Pakistan, India, Iran, Iraq, Syria, Russia and Central Asian neighbors.

Confusing scenarios

Still, the Islamic State-Khorasan (ISK) as IS is known in Afghanistan remains a fragmented group composed of differing regional forces with different agendas in different parts of the country.

“IS-K is still conducting low-level recruiting and distribution of propaganda in various provinces across Afghanistan, but it does not have the ability or authority to conduct multiple operations across the country,” a recent Pentagon report said. But where it operates, IS is inflicting chaos and casualties and causing confusing scenarios for disparate opponents.

In the Tora Bora area, where IS has made a strong stand in recent days, local villagers and militias joined with Taliban to rout IS. IS regained ground after a few days, leading to U.S. military air attacks on IS positions in conjunction with Afghan intelligence instructions and army operations.

IS fighters reportedly have fled from mountain caves of Tora Bora, where al-Qaida’s leader Osama bin Laden hid from U.S. attack in 2001.

Families displaced

IS fighters were also reportedly advancing in neighboring Khogyani district, displacing hundreds of families, according to district officials. It is one of several areas in Nangarhar province, near the Pakistani border, where IS has been active for over two years.

Fierce clashes in the Chaparhar district of Nangarhar last month left 21 Taliban fighters and seven IS militants dead, according to a provincial spokesman. At least three civilians who were caught in the crossfire were killed and five others wounded.

“IS has overpowered Taliban in some parts of Nangarhar because the Taliban dispatched its elite commando force called Sara Qeta (Red Brigade) to other parts of the country, including some northern provinces to contain the growing influence of IS there,” Wahid Muzhda, a Taliban expert in Kabul, told VOA.

ALSO READ: Flashback to Terror: 1993 Mumbai Blasts Judgement to Hail on June 27 After 24 Years

Recruiting unemployed youths

IS has also expanded in neighboring Kunar province, where, according to provincial police chief, it has a presence in at least eight districts and runs a training base, where foreign members of IS, train new recruits.

Hundreds of miles from Nangarhar, IS is attempting to establish a persistent presence in several northern provinces where it has found a fertile ground for attracting militants and recruiting unemployed youths, mostly between the age of 13 and 20.

IS has been able to draw its members from the Pakistani Taliban fighters, former Afghan Taliban, and other militants who “believe that associating with or pledging allegiance” to IS will further their interests, according to the Pentagon report.

Hundreds of militants have joined IS ranks in northern Jouzjan and Sar-e-Pul province where local militant commanders lead IS-affiliate groups in several districts.

Darzab district

Qari Hekmat, an ethnic Uzbek and former Taliban militant who joined IS a year ago, claims to have up to 500 members, including around 50 Uzbek nationals who are affiliated with the Islamic Movement of Uzbekistan (IMU) — previously associated with al-Qaida and Taliban in Afghanistan.

IS and Taliban are reportedly fighting over the control of Darzab district in Jouzjan which they stormed this week from two different directions and besieged scores of government forces. The Taliban has reportedly captured the center of the district while IS militants control the city outskirts.

Afghanistan faces a continuing threat from as many as 20 insurgent and terrorist networks present or operating in the Afghanistan-Pakistan region, including IS, the Pentagon said.

“In areas where the government has limited influence and control, IS attempts to emerge and expand there,” Ateequllah Amarkhail, an analysts and former Army general in Kabul told VOA.

Hit-and-hide strategy

IS has also claimed responsibility for several recent attacks in urban areas, however, with a hit-and-hide strategy that is proving effective. And it is engaging too in more skirmishes with U.S. forces that initially were sent to the country to help Afghan forces halt the spread of Taliban.

Three American service members based in eastern Afghanistan were killed in April during operations targeting IS militants, according to the Pentagon.

“ISIS-K remains a threat to Afghan and regional security, a threat to U.S. and coalition forces, and it retains the ability to conduct high-profile attacks in urban centers,” the Pentagon said. (VOA)