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This hot 'stream' of star gas will collide with our galaxy sooner than we thought


Oct 22, 2019
The article reports, "The team found that the two dwarf galaxies have been orbiting each other for only about 3 billion years. By the time the two galaxies were captured by the Milky Way, the Small Magellanic Cloud was orbiting counterclockwise around the Large one, spewing gas behind it and forming the Magellanic Stream."

3 billion is a short timescale. 40 dwarf galaxies are reported as recent arrivals to the MW too, only about 2 billion years ago. Gaia reveals that most Milky Way companion galaxies are newcomers to our corner of space, https://phys.org/news/2021-11-gaia-reveals-milky-companion-galaxies.html, Reference paper, Gaia EDR3 Proper Motions of Milky Way Dwarfs. II Velocities, Total Energy, and Angular Momentum, https://iopscience.iop.org/article/10.3847/1538-4357/ac27a8, 24-Nov-2021.

My observation. A dating issue in this report. 40 dwarf galaxies orbiting the Milky Way are recent arrivals, as the abstract indicates most within 2 billion years ago. That is a very young age compared to globular cluster H-R diagram ages, the age of the Milky Way, and Hubble time or age of the universe using BB model, redshifts, and Hubble Law. This is also very young compared to the 1950s, age of the solar system fixed at 4.56 billion years ago using meteorites. Now we see the LMC and SMC interacting for only about 3 billion years.

Using dating methods like this, more than plenty of action in the MW took place after the Sun is postulated to evolve from the solar nebula, 4.6 billion years ago, and long after the MW is said to form some 10 or 11 billion years ago.
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