Discovered galaxies to collide

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In the past 50 years, ground and space telescopes have detected hundreds of gamma ray bursts very powerful, which are now found a new use astronomical. One of these explosions, called GRB 090323, was discovered by Fermi gamma-ray telescope for NASA. Once its position was observed in detail by the Very Large Telescope (VLT) that the European Southern Observatory (ESO) has in Chile.

The astronomers, led by Sandra Savaglio, Max Planck Institute in Germany, concluded that the light from the explosion had crossed the galaxy where it occurred and also another nearby galaxy. "When we study the explosion was a surprise to see how the cold gas of these two galaxies, which are in the early universe and had elements much heavier than we knew at that moment in cosmic history," said Savaglio.

the gamma ray burst served to know that nearly 12.000 billion years the universe was already highly developed chemistry: gas acted as a filter for gamma rays, absorbing part of light. Without such a blast, both galaxies would have been invisible from Earth.

It was thought that heavy elements in galaxies were younger, like the Milky Way. These elements are produced from the life and death of several generations of stars, a cycle that is enriched gas from galaxies. This enrichment is used to study the history of galaxies.

However, the VLT has revealed that they also have a similar composition galaxies with 2.000 million years after the Big Bang.

"We've been lucky enough to observe the GRB 090323 as it remains bright enough, so it is possible to obtain detailed observations with the VLT dramatically. The only gamma-ray bursts remain bright for a short period of time and get transcendent data becomes a challenging task.

We expect to see these galaxies again in the future when we have much more sensitive instruments, "Savaglio said. ADS HERE