A star in a 15.2-year orbit around the supermassive black hole at the centre of the Milky Way

  title={A star in a 15.2-year orbit around the supermassive black hole at the centre of the Milky Way},
  author={Rainer Sch{\"o}del and Thomas Ott and Reinhard Genzel and Reiner Hofmann and Matthew D. Lehnert and Andreas Eckart and Nelly Mouawad and Tal Alexander and Mark J. Reid and Rainer Lenzen and Markus Hartung and François Lacombe and Daniel Rouan and Eric Gendron and G'erard Rousset and Anne-Marie Lagrange and Wolfgang Brandner and Nancy Ageorges and Christopher E. Lidman and A. F. M. Moorwood and Jason Spyromilio and Norbert N. Hubin and Karl M. Menten},
Many galaxies are thought to have supermassive black holes at their centres—more than a million times the mass of the Sun. Measurements of stellar velocities and the discovery of variable X-ray emission have provided strong evidence in favour of such a black hole at the centre of the Milky Way, but have hitherto been unable to rule out conclusively the presence of alternative concentrations of mass. Here we report ten years of high-resolution astrometric imaging that allows us to trace two… 
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Stellar Disk in the Galactic Center: A Remnant of a Dense Accretion Disk?
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The S-star cluster at the center of the Milky Way - On the nature of diffuse NIR emission in the inner tenth of a parsec
Sagittarius A*, the super-massive black hole at the center of the Milky Way, is surrounded by a small cluster of high velocity stars, known as the S-stars. We aim to constrain the amount and nature
On the Nature of the Compact Dark Mass at the Galactic Center
We consider a model in which Sgr A*, the 3.7 × 106 M☉ supermassive black hole candidate at the Galactic center, is a compact object with a thermally emitting surface. For very compact surfaces within


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Measurements of the accelerations of three stars from the central radio source Sagittarius A* increase the inferred minimum mass density in the central region of the Galaxy by an order of magnitude relative to previous results, and localize the dark mass to within 0.05 ± 0.04 arcsec of the nominal position of Sgr A*.
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Observations of stellar proper motions near the Galactic Centre
EVIDENCE for a massive black hole at the centre of our Galaxy has been accumulating for the past two decades 1−7. Estimates of the mass of this region have hitherto been based on the spectroscopic
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After a discussion of the properties of degenerate fermion balls, we analyze the orbits of the stars S0-1 and S0-2, which have the smallest projected distances to Sgr A*, in the supermassive black
The distance to the center of the Galaxy
For nearly a century astronomers have expended considerable effort to determine the size of the Milky Way. This effort is worthwhile because any change in the value of the distance from the Sun to
The Proper Motion of Sagittarius A*. I. First VLBA Results
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