Revealed the secret of cosmic dust


12/04/2012

Scientists have unraveled the long fired their minds the mystery of how dying stars eject material from which arise in the future new world.

It is known that the stars, including our sun, in the final phase of its existence, throw in a few years most of my weight to the outside. But only now able to understand how this happens.

Scientists reported in the journal Nature, which for this study they needed to use extraordinary methods.

They found that the size of emitted particles are about a million meters. Such a large size allows them pushed by light dying star.

A team of astronomers from the Australian and European universities, studied three red giant, which once were the same as our Sun is now. Once they have run out of stock hydrogen they grew to large sizes.

In the process, similar to the solar wind of our star, only much more intense, these stars spit out most of its mass in the form of gas and particles of mineral materials, turning into a white dwarf.

The lead author of the study, Barnaby Norris from the University of Sydney, said that these stars are "great utilizers matter galaxies" - the stuff they throw away, "is to create the next generation of stars and planets."

Up until now, remained a mystery to scientists how the process of release of the material. Computer model of the process showed that the particles emitted by stars are so small that they have a strongly adsorb light and heat, remaining in place.

To observe the cosmic dust around three red giants, Norris and colleagues used the Very Large Telescope in Chile, using a technique called interferometry Polarimetric.

This allowed to distinguish between objects, separated by just 15 billionths of a degree of the sky.

"This is equivalent to being in Sydney to make out a cup of coffee in Melbourne and determine its size," - said Norris.

The team saw that the scope of the dust surrounding the red dwarf, is smaller than many of the models shown - about two radii of the star itself.

After analyzing what he saw, the team determined the average size of the particles, which is just over half a million meters.

This is much more than previously thought. As explained by Norris, this size allows us to explain these mysterious particles ejected out: "Dust particles can be compared with small sails, the wind picks up, or, in this case, the light of a star."

"The mechanism of mass transfer from the stars, is one of the biggest questions of stellar astronomy, the answer to which depends on our understanding of the distribution of heavy elements in the galaxy. Our study has little to bring the answer to this global puzzle."

Original: Bbc


Dragon Spacecraft to the ISS cmozhete deliver ice cream
Mars rover "Opportunity" get out of Victoria Crater
NASA released images of asteroid 2012 DA14
Astronomers have discovered a factory for the production of supernovae
Residents of Colorado observed a mysterious UFO phenomenon