Earth became 25750 km/h faster and moved towards the supermassive black hole in 2000 light years

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The advice to look at yourself from the side is useful even in astronomy.
Earth just got 7 km/s (~25,750 km/h) faster and about 2,000 light-years closer to the supermassive black hole at the center of the Milky Way galaxy.

 

Earth just got 7 km/s (~25,750 km/h) faster and about 2,000 light-years closer to the supermassive black hole at the center of the Milky Way galaxy.

 

But don’t panic, this doesn’t mean we’re drifting towards a black abyss. These changes are the result of a better model of the Milky Way based on new observational data, which includes a catalog of objects observed by the Japanese radio astronomy project VERA for more than 15 years.

 

The VERA (VLBI Exploration of Radio Astrometry, and “VLBI” stands for Very Long Baseline Interferometry) project was launched in 2000 and is dedicated to the three-dimensional marking of velocities and positions of the spatial structures of the Milky Way. VERA’s interferometry technique combines data from radio telescopes located throughout the Japanese archipelago, achieving a resolution equivalent to a 2,300 km diameter telescope. This resolution provides an accuracy of 10 microseconds of arc – theoretically enough to see a 10-euro cent coin on the surface of the Moon.

 

Because Earth is inside the Milky Way galaxy, we can’t step back and see what our galaxy looks like from the side. Accurate measurement of the position and movement of objects – astrometry – plays a vital role in the general understanding of the structure of the Galaxy and our place in it. This year, the first VERA Astrometry Catalog was published, with data on 99 objects.

 

Based on new observations from the VERA Astrometry Catalog and other groups, astronomers have compiled a map of the objects’ positions and motions. Based on it, they calculated the center of the Galaxy – the point around which everything revolves.

According to this image, the galactic center and the supermassive black hole it contains are 25,800 light-years from Earth. This is closer than the official value of 27,700 light years adopted by the International Astronomical Union in 1985. According to the velocity component of the image, the Earth orbits the Galactic Center at a speed of 227 km/s. This is faster than the official value of 220 km/s.

 

VERA is now going to observe more objects, especially near the central supermassive black hole, to better characterize the structure and motion of the Galaxy. For this, VERA will participate in the EAVN (East Asian VLBI Network), a network of radio telescopes in Japan, South Korea and China. By increasing the number of telescopes and the distances between them, EAVN can achieve even greater precision.

 

VERA et al. sandabi’s “The First VERA Astrometry Catalog” appeared in the August 2020 Publications of the Astronomical Society of Japan.