The distance between our solar system and Sagittarius A *, the 4 million-solar-mass black hole in the center of our Milky Way galaxy, is about 25,800 light-years, closer to 1,900 light-years than previously estimated, according to a Japanese VLBI (very long baseline interferometer). Data analysis of Project VERA (VLBI Exploration of Radio Astrometry).
Location and velocity map of the Milky Way galaxy; Shows arrow position and velocity data for 224 for objects used in the Galaxy model; The solid black lines show the position of the spiral arm of the galaxy; Colors indicate groups of objects with similar hands. Image Credit: NAOJ.
Dr. Tom, an astronomer at the National Astronomical Observatory of Japan and the Mizusawa VLBI Observatory. “Because Earth is located inside the galaxy, we can’t move backwards and see what our galaxy looks like from the outside,” said Tomoya Hirota. Department of Astronomy at Sokendai, and its colleagues in collaboration with Vera.
“Astrology is an important tool for accurately measuring the position and motion of objects, the overall structure of the galaxy and our place in it.”
“The tax was introduced by Japan’s National Astronomical Observatory in the 2000s.”
“The project was created to be dedicated to VLBI astronomical observations, revealing 3D velocity and spatial structures in the galaxy.”
“It includes four 20-meter radio telescopes in Japan: at Mizusawa, Iriki, Ogasawara and Ishigaki-Jima stations.”
Using data from the first Vera Astrometry catalog, astronomers designed galaxies to estimate basic parameters such as the distance toward the center of the galaxy and the velocity of the Sun around it.
“Our results suggest that the center of the galaxy, and the supermassive black hole that resides there, is located 25,800 light-years from Earth.”
“This is closer to the official value of 27,700 light years adopted by the International Astronomical Union in 1985.”
“The velocity component of the map indicates that the sun is traveling 227 km / cm around the center of the galaxy. This is faster than the official value of 220 km / sec. “
VIRA researchers now plan to observe more objects objects, especially those close to Sagittarius A *, to better adapt to the formation and motion of the galaxy.
“As part of this effort, Vera will participate in EAVN (East Asian VLBI Network), which has radio telescopes based in Japan, South Korea and China,” he said.
“With the increase in the number of telescopes and the maximum separation between telescopes, EAVNs can achieve even greater accuracy.”
The VERA catalog was recently published Publications of the Astronomical Society of Japan.
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Tomoya Hirota Et al. (VERA Collaboration). 2020. First Vera Astrometry Catalog. Publications of the Astronomical Society of Japan 72 (4): 50; doi: 10.1093 / pasj / psaa018
