Talk:Galaxy formation and evolution
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Almost all galaxies have an extrememly large black hole at their center, or many tightly-packed neutron stars formed from collapsing supernovas over billions of years. All of the stars in the galaxy rotate around this massive center.
It has been suggested that the universe will end with neutrons as well, when all stars have collapsed into neutron stars and planets have been pulled into black holes. However, this may not happen for many billions of years.
- Maybe true, but it doesn't belong in Galaxy formation and evolution, and is not very well formulated.
What is better formulated are terms as top-down and bottom-up process models, Zel'dovich's pancake (originally crepe paper). Do someone have enow (an 'old' enough) time to define them better? After all 'at least' our Galaxy must have 'developed' from somewhere.
XJam [2002.03.26] 2 Tuesday (0)
The article currently claims that M31 has a lower mass than the Milky Way; I was fairly sure that it's the other way round, with M31 being about twice the MW's mass. Does anyone know for sure? Will check up on this when I get a chance. --Bth 01:28 Oct 1, 2002 (UTC)
M31 = Andromeda Galaxy ( >4.1 E11 solar masses), Milky Way (5 E11 solar masses) [1] (http://nedwww.ipac.caltech.edu/level5/ANDROMEDA_Atlas/Hodge_intro.html) & [2] (http://spiff.rit.edu/classes/phys240/lectures/local_group/local_group.html) --mav
The masses seem to be comparable, I really don't know how much effect a 20% diff or so can have, so I eliminated sentence about M31 being affected the most, for precaution. If somebody is familiar with simulations and is really sure of it, you are welcome to put the sentence back.--AN