Hubble Makes Surprising Find in the Early Universe

[HubbleSite]

In Greek mythology the first deities born from the universe's origin in "the Chaos," created a race of Titans. The powerful Titans were eventually superseded by the gods of Olympus. In modern cosmology, the stellar equivalent of the legendary Titans are so-called Population III stars, that would have been the very first stars born after the big bang. These hypothetical stars are as elusive as the Titans. Unlike the stars of today—like our Sun (that contains heavier elements, such as oxygen, nitrogen, carbon and iron)—the Population III stars would have been solely made out of the few primordial elements first forged in the seething crucible of the big bang. Much more massive and brighter than our Sun, they would have defiantly blazed as lords over the inky void of the newborn universe.

A team of European researchers, led by Rachana Bhatawdekar of the European Space Agency, set out to find the elusive first-generation stars by probing from about 500 million to 1 billion years after the big bang. In their quest they used observations from Hubble, NASA's Spitzer Space Telescope, and the ground-based Very Large Telescope of the European Southern Observatory. They used the gravitational lensing power of a massive foreground galaxy cluster (that acts as a giant magnifying lens in space) to find brightened images of far more distant background galaxies 10 to 100 times fainter than any previously observed. Unfortunately, the team found no evidence of these first-generation Population III stars in this cosmic time interval they explored. These results are nevertheless important because they show that galaxies must have formed even earlier after the big bang than previously thought.

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