Friday, August 20, 2010

The universe 'will expand forever',
new Nasa study on 'dark energy' concludes

The universe will continue to expand forever, Nasa scientists concluded in a new study that sheds light on one of the greatest astronomical puzzles, “dark energy”.

The universe 'will expand forever', new Nasa study on 'dark energy' concludes

The massive gravitational force of the dark matter (shown in blue) in giant galaxy cluster Abell 1689 bends the light from distant background galaxies, giving astronomers clues to the nature of dark energy. Photo: NASA/ JPL

Space agency researchers used the Hubble Space Telescope to “narrow in” on what they believe comprises the energy, which pushes our universe apart at ever-increasing speed.
Discovered it in 1998, astronomers have been unable to say what the mysterious force is, except that it is invisible and makes up a “large chunk of our universe”, or 72 per cent of its size.

Almost a quarter, 24 per cent, is thought to be "dark matter", which is also mysterious but easier to study than dark energy because of its “gravitational influence”.
The rest of the universe, a mere four per cent, is made of “the stuff that makes up people, planets, stars and everything made up of atoms”.
By using the huge “galactic magnifying lens” the international team of scientists, led by Nasa's Jet Propulsion Laboratory in Pasadena, California, concluded the distribution of dark energy would mean the universe would never stop growing.

The study, published in the journal Science on Thursday, also found it would eventually become a dead and cold wasteland.
The scientists used Hubble and European Space Observatory's Very Large Telescope to observe how light from distant stars became distorted around a nearby cluster of galaxies called Abell 1689.
The galaxies, found in the constellation of Virgo, is one of the biggest galactic clusters known to science.
Due to its huge mass, scientists say it “acts as a cosmic magnifying glass”, causing light to bend around it.
"We have to tackle the dark energy problem from all sides," said Prof Eric Jullo, a JPL scientist who led the international study.

"It's important to have several methods, and now we've got a new, very powerful one.
"What I like about our new method is that it's very visual. You can literally see gravitation and dark energy bend the images of the background galaxies into arcs.”

He said the study’s conclusion meant scientists could say for the first time that the expansion of the universe “will continue to accelerate and the universe will expand forever”.
Priya Natarajan, a cosmologist at Yale University, who was part of the team, added: “We can now apply our technique to other gravitational lenses.
SourceRelated Posts with Thumbnails
Bookmark and Share


Post a Comment

Thank you very much for your opinion

Related Posts Plugin for WordPress, Blogger...


View My Stats