# MEASURING DISTANCE AND PROPERTIES OF THE MILKY WAY'S CENTRAL SUPERMASSIVE BLACK HOLE WITH STELLAR ORBITS

@article{Ghez2008MEASURINGDA,
title={MEASURING DISTANCE AND PROPERTIES OF THE MILKY WAY'S CENTRAL SUPERMASSIVE BLACK HOLE WITH STELLAR ORBITS},
author={Andrea M. Ghez and Samir Salim and Nevin N. Weinberg and J. R. Lu and Tuan Do and J. K. Dunn and Keith Y. Matthews and Mark R. Morris and Sylvana Yelda and Eric Edward Becklin and Ted Kremenek and Milos Milosavljevic and Jill Naiman},
journal={The Astrophysical Journal},
year={2008},
volume={689},
pages={1044-1062}
}
• Published 21 August 2008
• Physics
• The Astrophysical Journal
We report new precision measurements of the properties of our Galaxy's supermassive black hole. Based on astrometric (1995-2007) and radial velocity (RV; 2000-2007) measurements from the W. M. Keck 10m telescopes, a fully unconstrained Keplerian orbit for the short-period star S0-2 provides values for the distance (R_0) of 8.0±0.6 kpc, the enclosed mass (M_(bh)) of 4.1±0.6x10^6 M☉ and the black hole's RV, which is consistent with zero with 30 km/s uncertainty. If the black hole is assumed to be…
1,134 Citations

## Figures and Tables from this paper

The Galactic Center: Improved Relative Astrometry for Velocities, Accelerations, and Orbits near the Supermassive Black Hole
• Physics, Geology
The Astrophysical Journal
• 2019
We present improved relative astrometry for stars within the central half parsec of our Galactic Center based on data obtained with the 10 m W. M. Keck Observatory from 1995 to 2017. The new methods
The Milky Way's circular velocity curve between 4 and 14 kpc from APOGEE data
• Physics
• 2012
We measure the Milky Way's rotation curve over the Galactocentric range 4 kpc R 14 kpc from the first year of data from the Apache Point Observatory Galactic Evolution Experiment. We model the
STELLAR POPULATIONS IN THE CENTRAL 0.5 pc OF THE GALAXY. I. A NEW METHOD FOR CONSTRUCTING LUMINOSITY FUNCTIONS AND SURFACE-DENSITY PROFILES
• Physics
• 2013
We present new high angular resolution near-infrared spectroscopic observations of the nuclear star cluster surrounding the Milky Way's central supermassive black hole. Using the integral-field
KECK OBSERVATIONS OF THE GALACTIC CENTER SOURCE G2: GAS CLOUD OR STAR?
• Physics
• 2013
We present new observations and analysis of G2—the intriguing red emission-line object which is quickly approaching the Galaxy's central black hole. The observations were obtained with the laser
Investigating the Relativistic Motion of the Stars Near the Supermassive Black Hole in the Galactic Center
• Physics
• 2017
The S-star cluster in the Galactic center allows us to study the physics close to a supermassive black hole, including distinctive dynamical tests of general relativity. Our best estimates for the
Investigating the Binarity of S0-2: Implications for its Origins and Robustness as a Probe of the Laws of Gravity around a Supermassive Black Hole
• Physics, Geology
• 2017
The star S0-2, which orbits the supermassive black hole (SMBH) in our Galaxy with a period of 16 years, provides the strongest constraint on both the mass of the SMBH and the distance to the Galactic
KINEMATICS OF THE STELLAR HALO AND THE MASS DISTRIBUTION OF THE MILKY WAY USING BLUE HORIZONTAL BRANCH STARS
• Physics
• 2012
Here we present a kinematic study of the Galactic halo out to a radius of ∼ 60 kpc, using 4664 blue horizontal branch (BHB) stars selected from the SDSS/SEGUE survey, to determine key dynamical
WISDOM Project – II. Molecular gas measurement of the supermassive black hole mass in NGC 4697
• Physics
• 2017
As part of the mm-Wave Interferometric Survey of Dark Object Masses (WISDOM) project, we present an estimate of the mass of the supermassive black hole (SMBH) in the nearby fast-rotating early-type
The Bar and Spiral Structure Legacy (BeSSeL) survey: Mapping the Milky Way with VLBI astrometry†
• Physics, Chemistry
• 2011
Astrometric Very Long Baseline Interferometry (VLBI) observations of maser sources in the Milky Way are used to map the spiral structure of our galaxy and to determine fundamental parameters such as
THE POWER SPECTRUM OF THE MILKY WAY: VELOCITY FLUCTUATIONS IN THE GALACTIC DISK
• Physics
• 2014
We investigate the kinematics of stars in the mid-plane of the Milky Way (MW) on scales between 25 pc and 10 kpc with data from the Apache Point Observatory Galactic Evolution Experiment (APOGEE),

## References

SHOWING 1-10 OF 87 REFERENCES
The accelerations of stars orbiting the Milky Way's central black hole
• Physics
Nature
• 2000
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*.
A Relationship between Nuclear Black Hole Mass and Galaxy Velocity Dispersion
• Physics
• 2000
We describe a correlation between the mass Mbh of a galaxy's central black hole and the luminosity-weighted line-of-sight velocity dispersion σe within the half-light radius. The result is based on a
High Proper-Motion Stars in the Vicinity of Sagittarius A*: Evidence for a Supermassive Black Hole at the Center of Our Galaxy
• Physics
• 1998
Over a 2 year period we have conducted a di†raction-limited imaging study at 2.2 km of the inner 6A ) 6A of the central stellar cluster of the Galaxy using the W. M. Keck 10 m telescope. The K-band
The Supermassive Black Hole at the Center of the Milky Way
• Physics
• 2004
We report the detection of a variable point source, imaged at L' (3.8 μm) with the Keck II 10 m telescope's adaptive optics system, that is coincident to within 18 mas (1 σ) of the Galaxy's central
Sagittarius A* “Visual Binaries”: A Direct Measurement of the Galactocentric Distance
• Physics
• 1999
We present a new geometrical method for measuring the distance to the Galactic center (R0) by solving for the Keplerian orbit of individual stars bound to the black hole associated with Sgr A* from
The First Measurement of Spectral Lines in a Short-Period Star Bound to the Galaxy’s Central Black Hole: A Paradox of Youth
• Physics
• 2003
We have obtained the first detection of spectral absorption lines in one of the high-velocity stars in the vicinity of the Galaxy's central supermassive black hole. Both Brγ (2.1661 μm) and He I
A star in a 15.2-year orbit around the supermassive black hole at the centre of the Milky Way
• Physics
Nature
• 2002
Ten years of high-resolution astrometric imaging allow us to trace two-thirds of the orbit of the star currently closest to the compact radio source (and massive black-hole candidate) Sagittarius A* and show that the star is on a bound, highly elliptical keplerian orbit around Sgr A*.
Periastron shifts of stellar orbits near the Galactic Center
• Physics, Geology
• 2001
The presence of a $2.9\pm0.4$ million solar mass object in the central stellar cluster of the Milky Way has recently been demonstrated via measurements of the stellar proper motions and radial
Luminous and dark matter in the Milky Way
• Physics
• 2001
Axisymmetric models of the Milky Way exhibit strong interrelations between the Galactic constants [the Sun's distance to the Galactic Centre (R0), and the local rotation speed (θ0)], the local
Stellar proper motions in the central 0.1 PC of the galaxy
• Physics
• 1997
We report the first results of a programme to measure proper motions of stars in the innermost core of the Galaxy. From high-resolution near-infrared imaging over the last four years we have