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The dynamical density of matter in the solar vicinity can be estimated using vertical oscillations of stars around the galactic plane. Öpik (1915) found that the summed contribution of all known stellar populations and interstellar gas is sufficient to explain the vertical oscillations of stars - in other words, there is no need to assume the existence of a dark population. Similar analyses were made by Kapteyn (1922) and Jeans (1922), who used the term "Dark Matter" to denote the invisible matter. Kapteyn found for the dynamical density of matter near the Sun 0.099 Modot / pc3, Jeans got 0.143 in the same units.

Oort (1932) analysis suggested that the total density is about 0.092 Modot / pc3, and the density of stars, including expected number of white dwarfs, is approximately equal to the dynamical density. He concluded that the total mass of nebulous or meteoric dark matter near the Sun is very small.

Kuzmin (1952, 1955) and his students Eelsalu (1959) and Jõeveer (1972, 1974) confirmed the earlier results by Öpik, Kapteyn and Oort. A number of other astronomers, including more recently Oort (1960) and Bahcall (1984, 1987), found results in agreement with the Jeans result. Their results mean that the amount of invisible matter in the solar vicinity should be approximately equal to a half of the amount of visible matter.

Modern data by Kuijken & Gilmore (1989), Gilmore et al. (1989) have confirmed the results by Kapteyn (1922), Oort (1932), Kuzmin (1952, 1955) and his collaborators. Thus we come to the conclusion that there is no evidence for the presence of large amounts of dark matter in the disk of the Galaxy. If there is some invisible matter near the galactic plane, then its amount is small, of the order of 15 percent of the total mass density.