The star that's ten million times brighter than the Sun!!!


Whoa!


The heaviest and brightest star known to exist – with a mass some 300 times as big as our own Sun – has been discovered by British astronomers who said yesterday that its existence defies current views on the maximum size of stellar objects.



The researchers found the star, known as R136a1, in a region of a neighbouring galaxy that is known to be a "cosmic factory". It exists inside the Tarantula Nebula of the Large Magellanic Cloud, more than 165,000 light years away from Earth, in an area where stars are being born from extensive clouds of gas and dust.

It is the biggest of a number of extremely rare "super heavyweight" stars that form in clusters so dense and bright that until now it has been impossible to distinguish between many of the individual objects. 

R136a1 is so bright that it would outshine the Sun by as much as the Sun outshines the Moon – a luminosity close to 10 million times greater than our own star.

"This is probably the most luminous star as well as the most massive star ever found. There are bigger stars in terms of physical size, it's just that this is the heaviest. It weighs about 300 million times more than the Earth," said Professor Paul Crowther, of Sheffield University, who led the study published in the journal Monthly Notices of the Royal Astronomical Society.

"These stars are born heavy and lose weight as they age. Being a little over a million years old, the most extreme star R136a1 is already 'middle-aged' and has undergone an intense weight-loss programme, shedding a fifth of its initial mass over the time, or more than 50 solar masses," Professor Crowther said.

The star is so massive that its gravitational attraction would easily outweigh that of our own star. If it could be swapped for the Sun, R136a1 would dramatically speed up the rate at which the Earth made its annual orbit around its star, according to Raphael Hirschi of Keele University. "Its high mass would reduce the length of the Earth's year to three weeks, and it would bathe the Earth in incredibly intense ultraviolet radiation, rendering life on our planet impossible," Dr Hirschi said. 

Using the European Southern Observatory's Very Large Telescope in Chile, Professor Crowther and his colleagues were able to distinguish between the super heavyweight stars in two different stellar clusters, known as R136, where the brightest and heaviest star is located, and NGC3603, which is about 22,000 light years from Earth.

Within the R136 cluster, the scientists estimate that only four stars weigh more than 150 times the mass of the Sun but even though there are about 100,000 stars within the cluster, these four heaviest objects account for nearly half of all the solar wind and radiation emitted from the cluster.

The new findings support the idea that there are lower size limits for stars. "The smallest stars [must be] more than 80 times the mass of Jupiter," said Olivier Schnurr, from the Astrophysics Institute in Potsdam, Germany. "Below that they are failed stars or brown dwarfs. Our new finding supports the previous view that there is also an upper limit to how big stars can get, but raises the limit by a factor of two, to about 300 solar masses."

In numbers
165,000 The distance in light years between R136a1 and the Earth
300 Number of Suns needed to equal the mass of the star. It is more than 300,000 times bigger than Earth
3 The length, in weeks, of a year on Earth if R136a1 was swapped with our own Sun. The huge gravitational pull would speed up the Earth's orbit and intense radiation would make life impossible
10,000,000 Number of Suns required to equal the brightness of the star. It outshines the Sun by as much as the Sun outshines the Moon

Courtesy: http://www.independent.co.uk/news/science/the-star-thats-ten-million-times-brighter-than-the-sun-2032215.html

AND DON'T FORGET TO CHECK OUT THIS VIDEO !!!
http://www.youtube.com/watch?v=WRYioSId2_E&feature=player_embedded 

The Everest is losing its cool!



Comparative photos of Mount Everest 'confirm ice loss'

The 1921 photo (left) and the photo taken from the same position 
in 2010  
Experts say comparing the 1921 photo (left) with the photo of 2010 proves that the ice mass is disappearing 
Photos taken by a mountaineer on Everest from the same spot where similar pictures were taken in 1921 have revealed an "alarming" ice loss.
The Asia Society (AS) arranged for the pictures to be taken in exactly the same place where British climber George Mallory took photos in 1921.
"The photographs reveal a startling truth: the ice of the Himalaya is disappearing," an AS statement said.


"They reveal an alarming loss in ice mass over an 89-year period."
Shrunken and withered The photos taken by Mallory from the north face of Everest reveal a powerful, white, S-shaped sweep of ice.
The 1921 image is in the foreground  
Experts say that the evidence is incontrovertible 
Images taken from the same spot in 2010 by mountaineer David Breashears show that the main Rongbuk Glacier is shrunken and withered.
"Returning to the exact same vantage points, Breashears has meticulously recreated their shots, pixel for pixel," the AS statement said.
"The photographs illustrate the severity of the loss of ice mass among the glaciers surrounding Mount Everest."
The AS says that the findings are "vitally important" because the Himalaya is home to the world's largest sub-polar ice reserves.
"The melt waters of these high altitude glaciers supply crucial seasonal flows to the Ganges, Brahmaputra, Salween, Irrawaddy, Mekong, Yangtze and Yellow rivers, which hundreds of millions of people downstream depend on for their livelihoods," the statement said.
"If the present rate of melting continues, many of these glaciers will be severely diminished by the middle of this century."
Mr Breashears retraced the steps of the 1921 British Mount Everest Reconnaissance Expedition Team, using photos taken then by surveyor and photographer Maj Edward Wheeler and amateur photographer George Mallory, who later died attempting to reach the Everest summit in 1924.
"The melt rate in this region of central and eastern Himalaya is extreme and is devastating," Mr Breashears told an AS meeting in New York on Wednesday.
He has not only followed in the footsteps of Mallory but also those of Italian photographer Vittorio Sella, whose work spanned the 19th and 20th Centuries.
The result is a then-and-now series of photographs from Tibet, Nepal and near K2 in Pakistan - all of which show glaciers in retreat.
"If this isn't evidence of the glaciers in serious decline, I don't know what is," Mr Breashears told the AFP news agency.
The issue of melting glaciers in the Himalaya is controversial following a recent claim in a UN report by an Indian glaciologist - who later said that he had been misquoted - that they could all disappear by 2035.

Courtesy:  http://www.bbc.co.uk/news/world-south-asia-10660130