Scientists Intrigued by Radio Signals Coming From Comet

"Each time it's come by for a visit, scientists have observed it giving off multiple outbursts of brightness and radio signals. The mechanism behind these flareups remains mysterious, but in the radio signals observed by Tianma last year, the team detected a spike in the spectral line associated with hydroxyl, a free radical made up of a hydrogen and oxygen atom, which is the result of water vapor being broken down by the Sun's radiation."

"During its 2024 approach, 12P became extremely bright as it neared the Sun. Using the Tianma to examine L-band and K-band radio waves, the researchers found that at a distance of one astronomical unit, or the average distance between the Earth and Sun, it released more than five tons of water vapor, which is far more material than other short- and long-period comets."

Comet 12P/Pons-Brooks was discovered in 1812 and returns roughly every 71 years as a Halley-type comet with orbital period between 20 and 200 years. Its prior close pass before 2024 occurred in 1954. The comet has produced multiple brightness and radio outbursts on previous visits. Radio observations with the Tianma Radio Telescope during the 2024 approach detected a spike in the hydroxyl spectral line, indicating water vapor photodissociation. Simulations of sunlight interaction with the surface modeled changing water production rates across outbursts and show far higher activity than other Halley-type comets. At 1 AU it released over five tons of water vapor.

Read at Futurism