Trigonometric Parallax of Sgr B 2
نویسندگان
چکیده
We have measured the positions of H2O 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, R0, of R0 = 7.9 +0.8 −0.7 kpc. The proper motion of Sgr B2 relative to Sgr A* suggests that Sgr B2 is ≈ 0.13 kpc nearer than the Galactic center, assuming a a low-eccentricity Galactic orbit. Subject headings: Galaxy: fundamental parameters, structure, kinematics and dynamics, halo — stars: formation — astrometry
منابع مشابه
o - ph . G A ] 2 6 A ug 2 00 9 A Trigonometric Parallax of Sgr B 2
We have measured the positions of H2O 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 R0 = 7.9 +0.8 −0.7 kpc. The proper motion of Sgr B2 rel...
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