Newfound 'Kraken merger' may have been the biggest collision in Milky Way's history

The article reported "Using artificial intelligence (AI) to match distinct clusters of stars by their ages, motions and chemical compositions, the team found evidence of five large-scale galactic mergers (each involving 100 million stars or more) dating back more than 10 billion years — including one ancient collision that has never been described before."

The article also reported "Using data obtained by the Gaia space probe (which has given us the most complete map of the Milky Way), the algorithm analyzed the ages, movements and chemical compositions of known globular clusters in our galaxy in order to recreate the cosmic mergers that landed them there. The team's analysis accurately predicted four known mergers in the Milky Way's past — including the so-called Gaia sausage merger, which added several billion stars to our galaxy's bulge about 9 billion years ago — as well as the previously unknown Kraken merger."

Interesting reconstructions of collisions dating back some 9 to 11 billion years ago. There is a new speed now for the Sun and Earth moving in the galaxy, 227 km/s. https://phys.org/news/2020-11-earth-faster-closer-black-hole.html, and "The First VERA Astrometry Catalog, https://academic.oup.com/pasj/article-abstract/72/4/50/5824859?redirectedFrom=fulltext, "Abstract We present the first astrometry catalog from the Japanese VLBI (very long baseline interferometer) project VERA (VLBI Exploration of Radio Astrometry)..." and the Sun is only about 25800 LY distance from Sgr A*, the black hole beast :)

Using the new velocity of motion for the Sun around our galaxy, semi-major axis of 7.92 kpc (from Sgr A*), eccentricity = 0.6, we have ~ 214 million year orbital period. It is good that the Sun was not moving around the galaxy during these collisions reported.

In 1E+9 years, the Sun completes 4.67 revolutions about the galactic center. In 4.5E+9 years, the Sun completes 21 galactic revolutions. None of this orbital *history* of the Sun can be verified by astrometry, stellar parallax changes or constellation changes.
 
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