In his first work “On the structure of atoms and molecules” (1913), Niels Bohr, as one of the proofs of the validity of the theory he developed, pointed to the fact that no more than 12 lines of the Balmer series are observed in the gas discharge tube, and in the celestial spectra bodies you can see 33 lines. Bohr explained this by saying that the diameter of a hydrogen atom cannot exceed the average distance between atoms, which depends on pressure. Based on these considerations, estimate the concentration of atoms, pressure and density of hydrogen in the gas-discharge tube and in the celestial body.

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