The physics of how gas accretes onto supermassive black holes is hugely important in astrophysics. It is a difficult topic of research however, involving three-dimensional, hot, magnetic plasmas. In a 2017 study, we used the G1 and G2 gas clouds in the Galactic center as probes of the accretion flow around SgrA*. As they plunge through the background gas, their orbits change due to dynamical friction. By analyzing these changes, we showed that the rotation axis of the accretion flow points along that of the Galaxy and of a putative jet! We also found that the pericenter passage date of G2 was delayed, due to precession of its eccentricity vector. It likely occured in August 2014, several months after the G2 observing campaign ended. Interestingly, this coincided with an increase in both the rate and luminosity of X-ray flares from SgrA*.
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