4/13/11

Master of News

Astronomers spy oldest known star

Paris - The first galaxies formed earlier than expected. The stars of a newly discovered galaxy formed only 200 million years after the Big Bang. These conclusions astronomers of the American and European space agencies, NASA and ESA data from the space telescope Hubble. The stars thus formed 13.5 billion years ago.
Only in January, Hubble discovered a galaxy that is about 13.2 billion years old. And in October, scientists had announced the discovery of a galaxy is 13 billion years old. Astronomers released the sensational new discoveries: "The first galaxies must be there much longer than we initially thought," said Dan Stark from the international research team.

The previously unknown, distant galaxy was the only scientist with a cosmic magnifying glass to see a so-called gravitational lensing. The star system is located behind a galaxy cluster called Abell 383, with the force of its mass - gravity - and thus deflects light beams strengthened. Even the largest telescopes available today were not following the experts detail the faint galaxy without the gravitational lens effect can perceive.

Dark Age

The astronomers studied the light spectrum of the galaxy and could thus determine its distance and age of their stars. The farther a galaxy away by the expansion of the universe, the farther its light in the red band is shifted. Although the redshift was measured only with 6, which corresponds to an age of about 12.8 billion years. But the study of faint stars have shown that the star system have already begun about 750 million years earlier must to take shape.

The study was the first galaxies, the scientists hope to solve the puzzle of how to spread after the Big Bang ultraviolet light in the dark space. Before that - in the so-called cosmic Dark Ages - swallowed a diffuse nebula of hydrogen gas almost any light. The astronomers have suggested that the first star systems with their radiation ionizes the gas and thus cleared the fog. Final statements they expect the technology of the Hubble's successor, "James Webb," to be placed earlier than 2014 into space.