Why is the dynamic mass of spiral galaxies an order of magnitude greater than their mass determined by the luminosity of stars?

The data on the rotation of spiral galaxies indicate that in galaxies, in addition to visible stellar matter, there is matter invisible in any spectral range, the so-called hidden mass. One of the assumptions about the nature of this substance is that it consists of very weakly interacting with ordinary matter of elementary particles: light with a mass of 10-14 – 10-10 proton masses, and heavy, with a mass of 1 – 1000 proton masses.

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