Infant Solar System with T Tauri Star May Have Windy Space Weather

Weather doesn't just occur here on Earth; it also occurs in space. Astronomers have used the ALMA telescope to spot what may be the first-ever signs of windy weather around a T Tauri star, which could explain why similar stars have disks that glow weirdly in infrared light while others shin in a more expected fashion.

T Tauri stars are young stars similar to our sun. They're relatively normal, medium-size stars that are surrounded by the raw materials to build both rocky and gaseous planets. While they're nearly invisible in optical light, the stars' disks shin in infrared and millimeter-wavelength light.

"The material in the disk of a T Tauri star usually, but not always, emits infrared radiation with a predictable energy distribution," said Colette Salyk, lead author of the new study, in a news release. "Some T Tauri stars, however, like to act up by emitting infrared radiation in unexpected ways."

While winds have been predicted by astronomers in the past, before now they've never clearly been detected. That's why researchers looked for evidence of a possible wind in AS 205 N, a T Tauri star located about 407 light-years away. Using ALMA, the researchers found that it exhibited a strange infrared signature and studied the distribution of carbon monoxide around the star.

So what did they find? It turns out that there was indeed gas leaving the disk's surface, which is what would be expected if a wind were present. Yet the properties of the wind didn't quite match expectations; this could be because the star may be part of a multiple star system.

"We are hoping these new ALMA observations help us better understand winds, but they have also left us with a new mystery," said Salyk. "Are we seeing winds, or interactions with the companion star?"

Currently, the scientists plant to continue their research with more ALMA observations. By targeting other T Tauri stars, they hope to get to the bottom of the mystery.

The findings are published in the Astrophysical Journal.