Two big Black Holes found together

Posted on March 5, 2009 by Rashid Faridi

Two colossal black holes appear to be orbiting one another in sort of a cosmic minuet at the center of a faraway galaxy formed when two separate galaxies collided, U.S. astronomers said on Wednesday. These two so-called supermassive black holes, which are celestial objects with enormous gravitational pull, are locked in orbit about 5 billion light years away from Earth, the scientists said. A light year is about 6 trillion miles (10 trillion km), or the distance light travels in a year. Data from Apache Point Observatory in New Mexico provided the best evidence to date of two black holes orbiting each other, according to astronomer Todd Boroson of the National Optical Astronomy Observatory in Tucson, Arizona. This is known as a binary system. Scientists believe all or most galaxies have supermassive black holes at their center. For example, our Milky Way galaxy has a black hole at its center that is about 3 million times the mass of the sun. When galaxies collide and merge, as they do relatively often, the black holes at their center may gravitate toward one another because of their great mass, entering into orbit as these two appear to be doing. Boroson said orbiting black holes eventually may merge into an even larger single black hole. While scientists think binary black holes may be relatively common, they have been elusive. Boroson and fellow National Optical Astronomy Observatory astronomer Tod Lauer detected these two by spotting the radiation emitted by objects apparently being sucked into the black holes by their gravitational pull. “You don’t see the black holes. You only see the effects of the black holes,” Boroson said in a telephone interview. The smaller of the black holes is about 20 million times the mass of our sun, while the larger one is a billion times the sun’s mass, the scientists wrote in the journal Nature. “We’ve discovered that there’s a pretty good correlation between the size of a black hole and the size of the galaxy that it’s in. This could be a case where a big galaxy ate a smaller galaxy,” Boroson said. These two black holes take about a hundred years to orbit each other and are located about three-tenths of a light year from each other, Boroson said.

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Chinaese Lunar Probe Ends Mission

Posted on March 4, 2009 by Rashid Faridi

China’s lunar probe has ended its 16-month life with a planned crash into the moon.Named for a moon goddess, the Chang’e-1 rammed into the lunar surface  after orbiting the moon thousandafters of times to map its surface.The probe was the first step in plans to land a vehicle on the moon in 2012. Before the moon-lander, China will send Chang’e-2 satellite to fulfill another mission.Last autumn China also launched its third manned space mission, with live-to-air footage of its first spacewalk captivating the nation.Beijing officials have said the country is looking to eventually put astronauts on the moon, but the government has not announced any schedule for that task.

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Saltwater solution to save crops

Posted on March 3, 2009 by Rashid Faridi

Technology under development at the University of New South Wales could offer new hope to farmers in drought-affected and marginal areas by enabling crops to grow using salty groundwater.

Associate Professor Greg Leslie, a chemical engineer at UNSW’s UNESCO Centre for Membrane Science and Technology, is working with the University of Sydney on technology which uses reverse-osmosis membranes to turn previously useless, brackish groundwater into a valuable agricultural resource.

“We are looking at ways to grow plants on very salty water without damaging soil,” Professor Leslie said.

“We’re incorporating a reverse osmosis membrane into a sub-surface drip irrigation system.”

The irrigation system relies on the roots of the plant drawing salty groundwater through the membrane — in doing so removing the salt which would otherwise degrade the soil and make continued cropping unsustainable.

Desalination such as this requires a pressure gradient to draw clean water through the membrane. Professor Leslie has demonstrated that, by running irrigation lines under the ground beneath the plants, the root systems of the plants provide enough of a pressure gradient to draw up water without the high energy consumption usually required for desalination.

“We’re going to provide agriculture with a tool to grow crops in drought years when there is limited access to run-off and surface water,” he said.

The membrane technology, developed by Professor Leslie and the University of Sydney’s Professor Bruce Sutton, has been patented by UNSW’s commercial arm, NewSouth Innovations.

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Posted in BIODIVERSITY, Environment, food security, water | 1 Comment

Mumbai, India Civic Body to take up Aerial Mapping

Posted on March 2, 2009 by Rashid Faridi

The BMC will no longer rely on archaic maps while drawing up plans against natural disasters such as floods. Claimed to be a first of its kind initiative (first municipal corporation in Asia), civic officials will travel on a private helicopter on Thursday to capture vital locations and flood-prone areas on a camera. The flight will cross the city over a period of one month to complete the process. The permission to carry out low-lying aerial photography required for contour mapping in the city came from the Ministry of Defence (MoD) last month. Contour mapping is a significant aspect of the flood modelling system which is practised worldwide. After the deluge in June 2005, the Madhav Chitale Committee had emphasised the need for a fool-proof flood system to guide civic authorities during rescue efforts. The committee had recommended that a contour map survey be conducted, recording the contours at intervals of 5 metres. The BMC has appointed two private firms – MWH from Mumbai and ORG from Gurgaon – to carry out the exercise.

Source : http://timesofindia.indiatimes.com

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