Dwarf spheroidal galaxies

Dwarf spheroidal galaxies - a fascinating topic for a first course in philosophy of science.

The options that remain open as of January 2013 are remarkable : dark matter, revised Newtonian laws, …

Related : the galactic rotation problem; formation of barred-spiral galaxies

Web astronomy of related interest : the Sloan digital survey's colliding galaxies as categorized by the GalaxyZoo social astronomy image project.

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