Why do astronomers rule out dim stars as the most important component of dark matter?

Answer 1

Dim stars are still visible. Scientists know how dim stars work. Dark matter works in a different way.

Take a paper plate and make a diagram of the planets in their proper order with the sun in the middle of the plate. Take the earth and draw a circle completely around the plate. Take Mars and draw a circle 1/2 way around the plate. Take Jupiter and draw a circle 1/12 around the plate. Take Saturn and draw a circle 1/30 around the circle.

Take a second paper plate. Right in the center put a big black dot for a black hole. Then go a little out, a little larger than a quarter and make it white for the central bulge. Now we will use half the diameter of the plate filling in groups of stars. Put in a group here and a group there. Now draw lines showing that every group goes at the same speed as it orbits the center of the galaxy.

It does not act like the planets of the solar system. So the dark matter must be out beyond the edge of the stars to make the galaxy spin like it does. It does not bend light as it should if it consisted of dim stars. It is flat like your paper plate otherwise it would make this galaxy spherical. Still, it makes the galaxy act like a drawing on a paper plate.

Answer 2

Stars emit light. By definition, "dark" matter does not. Thus, dark matter can not be stars.