A gas cloud on its way towards the supermassive black hole at the Galactic Centre

@article{Gillessen2011AGC,
  title={A gas cloud on its way towards the supermassive black hole at the Galactic Centre},
  author={Stefan Gillessen and Reinhard Genzel and Tobias Fritz and Eliot Quataert and Christian Alig and Andreas Burkert and Jorge Cuadra and Frank Eisenhauer and Oliver Pfuhl and Katie Dodds-Eden and Charles F. Gammie and Thomas Ott},
  journal={Nature},
  year={2011},
  volume={481},
  pages={51-54}
}
Measurements of stellar orbits provide compelling evidence that the compact radio source Sagittarius A* at the Galactic Centre is a black hole four million times the mass of the Sun. With the exception of modest X-ray and infrared flares, Sgr A* is surprisingly faint, suggesting that the accretion rate and radiation efficiency near the event horizon are currently very low. Here we report the presence of a dense gas cloud approximately three times the mass of Earth that is falling into the… 

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