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Wednesday, July 8, 2009

Faraway supernovae shatter distance record Astronomers say stellar blasts occurred 11 billion years ago

"The remnants of two massive stars that exploded about 11 billion years ago have shattered the record for the most distant supernovae in the known universe.

The faraway explosive remnants, found using a new method, could help researchers learn more about the evolution of the universe, how the elements in it formed and how they were distributed in later generations of stars and planets.

"When stars explode, they spew matter into space. Eventually, gravity collapses the matter into a new star, which could have planets such as Earth around it," said study leader Jeff Cooke of the University of California at Irvine.
Before the discovery of these supernovae, which belong to a category known as Type IIn, the most distant known supernovae of the same type were 6 billion light-years away, and the most distant of any supernova type were 9 billion light-years away.

A supernova occurs when a massive star (more than eight times the mass of the sun) dies in a powerful explosion. Type IIn supernovae result from the explosive death of stars that are 50 to 100 times the mass of the sun. These stars shed most of their material before they die, and when they finally explode the remaining material is spewed out into space, plowing through the previously expelled gas. The collisions between the gas clouds make the entire stellar remnant gleam brightly for several years after the star's demise.

To find supernovae, astronomers compare images of the same area of the sky taken at different times. A new pinprick of light that appears in one image and seems to fade over time can indicate the temporary brightening and dimming of the stellar explosion.
Cooke and his colleagues used a variation on this traditional method: They examined combined data from the Canada-France-Hawaii Telescope Legacy Survey for the same patch of sky for four different years. By comparing the images, Cooke's team identified four very distant objects that appeared to brighten and fade over time.

The data showed that the light from the supernovae had traveled nearly 11 billion light-years to reach Earth. That means the explosions happened 11 billion years ago, and the light is just now reaching us.

"The universe is about 13.7 billion years old, so really we are seeing some of the first stars ever formed," Cooke said.
Cooke's technique is "powerful and reliable," said astronomer Alicia Soderberg of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. Soderberg was not involved in the new study, which is detailed in Thursday's issue of the journal Nature.

The new method should make it possible to identify even more distant supernovae, possibly even some of the very first stars that blew apart. Other efforts already planned, such as the Large Synoptic Survey Telescope, could identify thousands of candidate supernovae.

"This new method could not have been published at a better time," Soderberg said."


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Thoughts worth thinking about

"Our subconscious minds have no sense of humor, play no jokes and cannot tell the difference between reality and an imagined thought or image. What we continually think about eventually will manifest in our lives."-Sidney Madwed

Laws alone can not secure freedom of expression; in order that every woman and man present their views without penalty, there must be spirit of tolerance in the entire population.- Albert Einstein Too often we underestimate the power of a touch, a smile, a kind word, a listening ear, an honest compliment, or the smallest act of caring, all of which have the potential to turn a life around. - Leo Buscaglia

A person's true wealth is the good he or she does in the world. - Mohammed

Our task must be to free ourselves... by widening our circle of compassion to embrace all living creatures and the whole of nature and its beauty. -Albert Einstein

The best way to find yourself, is to lose yourself in the service of others. - Ghandi

The unselfish effort to bring cheer to others will be the beginning of a happier life for ourselves. - Helen Keller

Aim for success, not perfection. Never give up your right to be wrong, because then you will lose the ability to learn new things and move forward with your life. Remember that fear always lurks behind perfectionism. Confronting your fears and allowing yourself the right to be human can, paradoxically, make yourself a happier and more productive person. - Dr. David M. Burns

Life is as dear to a mute creature as it is to man. Just as one wants happiness and fears pain, just as one wants to live and not die, so do other creatures. -His Holiness The Dalai Lama

Mankind's true moral test, its fundamental test (which lies deeply buried from view), consists of its attitude towards those who are at its mercy: animals. And in this respect mankind has suffered a fundamental debacle, a debacle so fundamental that all others stem from it. -

Milan Kundera, The Unbearable Lightness of Being

The worst sin towards our fellow creatures is not to hate them, but to be indifferent to them. That's the essence of inhumanity. -George Bernard Shaw

Ego's trick is to make us lose sight of our interdependence. That kind of ego-thought gives us a perfect justification to look out only for ourselves. But that is far from the truth. In reality we all depend on each other and we have to help each other. The husband has to help his wife, the wife has to help the husband, the mother has to help her children, and the children are supposed to help the parents too, whether they want to or not.-Gehlek Rinpoche Source: "The Best Buddhist Writing 2005 pg. 165

The hostile attitude of conquering nature ignores the basic interdependence of all things and events---that the world beyond the skin is actually an extension of our own bodies---and will end in destroying the very environment from which we emerge and upon which our whole life depends.