Guardian: On 15 August 1977, a powerful blast of radio waves lasting 72 seconds was detected coming from a group of stars called Chi Sagittarii by astronomer Jerry Ehman of the Ohio State University. Long thought to indicate the existence of an extraterrestrial intelligence, the so-called Wow! signal has not been observed since. Now Antonio Paris of St. Petersburg College in Florida may have a more mundane explanation. Paris found that two comets—266P/Christensen and 335P/Gibbs—were both near Chi Sagittarii the day the Wow! signal was detected. Comets are surrounded by clouds of hydrogen gas and can emit radio frequencies similar to those detected by Ehman. To test his hypothesis, Paris hopes to observe the next passage of the two comets past Chi Sagittarii in 2017 and 2018 and has launched a crowdfunding campaign to raise the $13 000 needed to buy a radio telescope to do so.
The finding that the Saturnian moon may host layers of icy slush instead of a global ocean could change how planetary scientists think about other icy moons as well.
Modeling the shapes of tree branches, neurons, and blood vessels is a thorny problem, but researchers have just discovered that much of the math has already been done.
January 29, 2026 12:52 PM
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