A TRIGONOMETRIC PARALLAX OF Sgr B2

Journal Article · Tue Nov 10 04:00:00 EST 2009 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/705/2/1548· OSTI ID:21378259

Reid, M J ^[1]; Menten, K M; Brunthaler, A ^[2]; Zheng, X W ^[3]; Xu, Y ^[4]

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1. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)
2. Max-Planck-Institut fuer Radioastronomie, Auf dem Huegel 69, 53121 Bonn (Germany)
3. Department of Astronomy, Nanjing University, Nanjing 210093 (China)
4. Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008 (China)

We have measured the positions of H{sub 2}O masers in Sgr B2, a massive star-forming region in the Galactic center, relative to an extragalactic radio source with the Very Long Baseline Array. The positions measured at 12 epochs over a time span of one year yield the trigonometric parallax of Sgr B2 and hence a distance to the Galactic center of R {sub 0} = 7.9{sup +0.8} {sub -0.7} kpc. The proper motion of Sgr B2 relative to Sgr A* suggests that Sgr B2 is approx0.13 kpc nearer than the Galactic center, assuming a low-eccentricity Galactic orbit.

• OSTI ID: 21378259
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 705; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
AMPLIFIERS
DISTANCE
ELECTRONIC EQUIPMENT
EQUIPMENT
GALAXIES
HYDROGEN COMPOUNDS
MASERS
MICROWAVE AMPLIFIERS
MICROWAVE EQUIPMENT
MOTION
ORBITS
OXYGEN COMPOUNDS
PROPER MOTION
STARS
WATER