By Moni Basu, CNN
(CNN) -- Imagine a star so luminous that it would burn the Earth up if it were anywhere near, a star that outshines the sun as much as the sun outshines the moon. A monster even in the abyss of space.
The star is not some scientist's celestial dream. Astronomers used a Very Large Telescope -- the instrument's official name -- to detect the most massive star discovered to date. In scientific lingo, it's a "hypergiant."
Led by Paul Crowther, professor of astrophysics at England's University of Sheffield, the team of astronomers studied two young clusters of stars, NGC 3603 and RMC 136a.
R136a1, found in the RMC 136a cluster, is 10 million times brighter than the sun and is the heaviest star ever found, Crowther said Wednesday, with a mass that is roughly 265 times more than the sun. It was born even heavier, with a solar mass of 320. Astronomers previously thought 150 to be the upper limit.
Several of the stars studied had surface temperatures of 40,000 degrees, more than seven times hotter than the sun.
R136a1 is rare and resides in another galaxy called the Large Magellanic Cloud. Its home is more than 165,000 light years away from Earth's Milky Way galaxy. As such, said Crowther, it is not visible to the naked eye, nor with a rooftop telescope.
"Owing to the rarity of these monsters, I think it is unlikely that this new record will be broken any time soon," Crowther said.
Crowther's team used the sophisticated infrared equipment on the Very Large Telescope in a European Southern Observatory facility in Chile as well as data collected from the Hubble Space Telescope to detect the colossal star. The telescope is considered the world's "biggest eye on the sky" and is 8 meters (26 feet) in diameter.
The research was published in the current issue of the British scientific journal The Monthly Notices of the Royal Astronomical Society.
"Unlike people, these kind of stars are massive when they are babies," Crowther told CNN. "They lose weight as they get older."
At over a million years old, the star is already middle-aged, Crowther said, and could easily be a poster child for WeightWatchers, having shed a fifth of its initial mass over time because of powerful winds.
In another million years -- a brief life span compared to the sun's 5 billion years of existence -- the giant star will probably explode as a supernova. It won't be noticeable on Earth because it's so far away.
Crowther, excited about the new find, had to find simple terminology to describe it to his 6-year-old son Billy. Billy, in turn, wanted dad to name the monster star after him.
That might have sounded a whole lot better than R136a1, but nonetheless, a star is born.
Source: CNN.com
Wednesday, July 21, 2010
Without rain, Angat may have only 40-days supply of water
If the rains do not come yet, the Angat Dam reservoir, which provides 97 percent of the water needs of the national capital region, may not have enough water to supply Metro Manila and other provinces after 40 days, the National Power Corporation said Wednesday.
Angat Dam is a multi-purpose facility that supplies potable drinking water to Metro Manila and nearby provinces. It also irrigates farmlands in nearby provinces and augments power supply for the Luzon Grid.
Napocor president Froilan Tampinco said the water at the dam will not last for 40 days if the rains will not yet come and the water level remains at 158.2 meters above sea level (MASL), way below the critical level of 180 MASL.
“Kung walang ulan, remember we are releasing through the low level outlet, kung bumaba yun doon, kahit gusto natin maglabas ng tubig, walang lalabas (If there is no rain, remember that we are releasing through the low level outlet, even if we want to release water, nothing will come out)," Tampinco said.
“We need more rainfall but not the kind that would cause destruction. We just need heavy rainfall," he said. The rainfall should be at least 50 milliliters per day for one month to reach the 180 MASL level.
Tampinco said the Angat dam water level is expected to reach 180 MASL by September, noting that the Metropolitan Waterworks and Sewerage System (MWSS) and the water concessionaires rely on the data from the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA).
He said the decrease of water from the dam is not due to evaporation but more on the lack of inflow.
“Hindi nadadagdagan, nagbababawas lang tayo ng tubig (There's no new supply; we are just decreasing the current supply of water)," Tampinco said.
Tampinco also clarified that the water shortage is largely due to lack of rainfall and not because of the alleged overspilling from the dam from December 1 to 15 last year.
“What we are realizing now as a situation is to our analysis, largely due the weather, which was caused by the lack of proper inflow of water into the dam. It is not because of the releases that we have made," he said.
“It is best for the agencies concerned to sit down and talk things over and look for solutions. I don’t think it will be productive for us to pinpoint and blame anybody," Tampinco said.
Tampinco said cloud seeding can help increase the water level but it also carries risks.
“What we can cite is what experienced recently, and we had an increase of about 0.6 meters. The water level in Angat actually increased, because of the rains that we have been experiencing. Of course, it’s not enough but still significant, and if this trend goes on, we may be able to reach a level when things are comfortable and normal," he said.
Napocor said in a separate statement that the agency tried to implement measures to ensure that Angat dam will have enough water, in anticipation of an El Nino period as forecast by the PAGASA, the state weather forecasting agency.
Expecting an extended summer as predicted by PAGASA, Napocor maintained the water in the dam above the normal operational level by more than two meters to 212 MASL from 210 MASL as of December 2009.
"Our total outflows were only almost 93 million cubic meters (MCM) from December 1 to 15, 2009; which is even lower than the more than 108 MCM – the requirement of both the National Irrigation Administration and MWSS for the same period," Napocor said.
It added that all the water releases during that period were within dam operation protocols and regulatory requirements.
“There are no releases made for that period that are outside the allocations given by the National Water Resources Board (NWRB). There were no extra releases, contrary to the allegations," Napocor said.
"However, dam water release is not an exact science. There will always be discrepancies, because of the nature of water itself. Its not like you can measure the volume as it flows down exactly to the last drop. What is important is that we were able to maintain the level of water released, on the average, as required by the NWRB," Napocor said. –VVP/JV, GMANews.TV
Angat Dam is a multi-purpose facility that supplies potable drinking water to Metro Manila and nearby provinces. It also irrigates farmlands in nearby provinces and augments power supply for the Luzon Grid.
Napocor president Froilan Tampinco said the water at the dam will not last for 40 days if the rains will not yet come and the water level remains at 158.2 meters above sea level (MASL), way below the critical level of 180 MASL.
“Kung walang ulan, remember we are releasing through the low level outlet, kung bumaba yun doon, kahit gusto natin maglabas ng tubig, walang lalabas (If there is no rain, remember that we are releasing through the low level outlet, even if we want to release water, nothing will come out)," Tampinco said.
“We need more rainfall but not the kind that would cause destruction. We just need heavy rainfall," he said. The rainfall should be at least 50 milliliters per day for one month to reach the 180 MASL level.
Tampinco said the Angat dam water level is expected to reach 180 MASL by September, noting that the Metropolitan Waterworks and Sewerage System (MWSS) and the water concessionaires rely on the data from the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA).
He said the decrease of water from the dam is not due to evaporation but more on the lack of inflow.
“Hindi nadadagdagan, nagbababawas lang tayo ng tubig (There's no new supply; we are just decreasing the current supply of water)," Tampinco said.
Tampinco also clarified that the water shortage is largely due to lack of rainfall and not because of the alleged overspilling from the dam from December 1 to 15 last year.
“What we are realizing now as a situation is to our analysis, largely due the weather, which was caused by the lack of proper inflow of water into the dam. It is not because of the releases that we have made," he said.
“It is best for the agencies concerned to sit down and talk things over and look for solutions. I don’t think it will be productive for us to pinpoint and blame anybody," Tampinco said.
Tampinco said cloud seeding can help increase the water level but it also carries risks.
“What we can cite is what experienced recently, and we had an increase of about 0.6 meters. The water level in Angat actually increased, because of the rains that we have been experiencing. Of course, it’s not enough but still significant, and if this trend goes on, we may be able to reach a level when things are comfortable and normal," he said.
Napocor said in a separate statement that the agency tried to implement measures to ensure that Angat dam will have enough water, in anticipation of an El Nino period as forecast by the PAGASA, the state weather forecasting agency.
Expecting an extended summer as predicted by PAGASA, Napocor maintained the water in the dam above the normal operational level by more than two meters to 212 MASL from 210 MASL as of December 2009.
"Our total outflows were only almost 93 million cubic meters (MCM) from December 1 to 15, 2009; which is even lower than the more than 108 MCM – the requirement of both the National Irrigation Administration and MWSS for the same period," Napocor said.
It added that all the water releases during that period were within dam operation protocols and regulatory requirements.
“There are no releases made for that period that are outside the allocations given by the National Water Resources Board (NWRB). There were no extra releases, contrary to the allegations," Napocor said.
"However, dam water release is not an exact science. There will always be discrepancies, because of the nature of water itself. Its not like you can measure the volume as it flows down exactly to the last drop. What is important is that we were able to maintain the level of water released, on the average, as required by the NWRB," Napocor said. –VVP/JV, GMANews.TV
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