A Geometric Determination of the Distance to the Galactic Center

  title={A Geometric Determination of the Distance to the Galactic Center},
  author={Frank Eisenhauer and Rainer Schoedel and Reinhard Genzel and Thomas Ott and Matthias Tecza and Roberto Abuter and Andreas Eckart and Tal Alexander},
  journal={The Astrophysical Journal Letters},
  pages={L121 - L124}
We report new astrometric and spectroscopic observations of the star S2 orbiting the massive black hole in the Galactic center that were taken at the ESO VLT with the adaptive optics-assisted, near-IR camera NAOS/CONICA and the near-IR integral field spectrometer SPIFFI. We use these data to determine all the orbital parameters of the star with high precision, including the Sun-Galactic center distance, which is a key parameter for calibrating stellar standard candles and an important rung in… 

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