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Article: With a twinkle, pulsating stars could deliver signals from ET: neutrino beams may turn Cepheids into messengers.(STORY ONE)
- Article from:
- Science News
- Article date:
- October 11, 2008
- Author:
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Searching for signals from extraterrestrials can be a ticklish business. Astronomer John Learned thinks tickling certain stars in just the right way might be a good strategy for ET to phone Earth.
Those stars, known as Cepheid variables, brighten and dim on a regular schedule. In 1908, after analyzing stars on photographic plates at Harvard College Observatory, Henrietta Swan Leavitt reported that a Cepheid's maximum brightness depends on the timing of its bright-dim cycle. The longer the period, the brighter the star. Other astronomers soon realized that they could use the period-brightness relationship to measure distances to remote galaxies.
A century ...