The newly discovered gas cloud, known as G2t, shares an almost identical orbit with two previously identified clouds, indicating that they may have originated from a pair of massive stars situated near the Milky Way’s core.

This VLT image illustrates the stars and gas surrounding Sagittarius A*, the supermassive black hole at the center of the Milky Way. Image credit: ESO/D. Ribeiro, MPE GC Team.

“This is a dynamic environment where stars and gas clouds orbiting the black hole move at astonishing speeds,” remarked Dr. Stefan Gillessen from the Max Planck Institute for Extraterrestrial Physics.

“While the gas clouds G1 and G2 were previously known, their origins and compositions remained subjects of debate.”

“Specifically, questions arose about whether these clouds contained hidden stars or were purely gaseous.”

“With the identification of G2t, we are starting to unravel these mysteries.”

G2t was detected using the High-Resolution Imager and Spectrograph (ERIS) on the ESO’s Very Large Telescope (VLT).

“Thanks to the VLT, we successfully measured the 3D orbit of this gas cloud around the black hole,” the team explained.

“G2t traverses a remarkably small area within this expansive image of the center.”

“Interestingly, G1, G2, and G2t are found to have nearly identical orbits, albeit slightly tilted in relation to one another.”

“The odds of different stars maintaining such similar orbits are minimal, further suggesting that each cloud does not harbor a star at its core.”

“These orbital similarities indicate that all three clouds likely stem from the same source, most probably IRS16SW, a pair of massive stars that discharge substantial quantities of gas.”

“As IRS16SW moves around the black hole, each gas cloud is ejected on a slightly different trajectory, explaining the subtle variations observed among the ‘G-triplets.’

“This finding highlights that despite years of observing our galaxy’s center, fresh enigmas await discovery,” the researchers noted.

“What could be more thrilling than a mystery poised to be unraveled?”

For more about this discovery, refer to the paper published in the journal Astronomy and Astrophysics.

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S. Gillessen et al. 2026. Gas streamer G1-2-3 at the center of the galaxy. A&A 707, A79; doi: 10.1051/0004-6361/202555808