Gas cloud G2 in galactic center may be part of extensive gas streamer

The astronomers have recently discovered that the orbit of gas cloud G2 in galactic center matches that of another gas cloud detected a decade ago, which might mean that it is part of a much more extensive gas streamer.

This would also match some of the proposed scenarios that try to explain the presence of G2. One such model was that G2 was originating from the wind from a massive star.

The gas cloud G2 was originally detected by Stefan Gillessen and his colleagues at the Max Planck Institute for Extraterrestrial Physics (MPE) in 2011.

It is on a highly eccentric orbit around the galactic center and observations in 2013 have shown that part of the gas cloud is already past its closest approach to the black hole, at a distance of roughly 20 light-hours.

The new, deep infrared observations with the SINFONI instrument at the VLT track the ongoing tidal disruption of the gas cloud by the powerful gravitational field. While the shape and path of the gas cloud agrees well with predictions from the models, so far there has been no significant enhanced high-energy emission, as one might have expected from the associated shock front.

Moreover, the gas streamer picture could also help to explain the missing X-ray emission from the gas cloud near the black hole, although the non-detection of such emission is not yet understood.