More than 20,000 radio antennas will soon connect over the Internet to scan largely unexplored radio frequencies, hunting for the first stars and galaxies and potentially signals of extraterrestrial intelligence.

The Low Frequency Array (LOFAR) will consist of banks of antennas in 48 stations in the Netherlands and elsewhere in Europe, all hooked up by fiber optic cables. Signals from these stations will be combined using a supercomputer, transforming the array into "perhaps the most complex and versatile radio telescope ever attempted," said Heino Falcke, chairman of the board for the International LOFAR Telescope.

Currently 16,000 of LOFAR's antennas and 41 of its stations are up, and the array will be completed by the middle of this year. All told, LOFAR will have a resolution equivalent to a telescope 620 miles (1,000 kilometers) in diameter. In addition, "it's an expandable design — we can always come along later and add additional stations," said Michael Wise at ASTRON, the Netherlands Institute for Radio Astronomy.

Since LOFAR is so large, it can scan large parts of the heavens — its first all-sky survey, which started Jan. 9, can sweep across "the entire northern sky twice in just 45 days," said George Heald of ASTRON.

LOFAR is also very fast, capable of measuring events only five-billionths of a second long. In addition, the fact that LOFAR is essentially many different radio telescopes knit together means it can run, say, three different science projects simultaneously, Wise said.

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