Princip setrvačníku je znám několik tisíc let. Velmi dlouho se setrvačník využívá ke stabilizaci otáček nejrůznějších točivých strojů, včetně automobilů. V poslední době objev vysokoteplotní supravodivosti umožnil konstrukci setrvačníků s levitačním závěsem, které slibují využití pro stabilizaci parametrů rozvodných elektrických sítí nebo k akumulaci elektrické energie., The principles of gyroscope have been known for thousands years. For a long time gyroscopes have been employed for stabilization of revolution speed in various rotational machines, including automobiles. Recently, the discovery of high temperature superconductivity enabled the construction of flywheels (gyroscopes with a levitation suspension) that promise a wide use in stabilization of a number of parameters of the electric energy distribution network and in electric energy accumulation., Miloš Jirsa., and Obsahuje bibliografii
The dust production rates of all the known periodic comets, calibrated by the measurements from the 1986 apparition of comet Halley, are ušed to compute their dust input into the region inside the earth orbit, and the resulting dust fluxes at R = 1 AU. The spatial distribution of tho fresh ejecta and the teraporal variations of their accumulation are reconstructed. Tho visible release of dust is evidently insufficient to maintain the zodiacal cloud in equilibrium.
It is suggested that the progressive decay of the dark matter, including extinct cometary nuclei, their fragments, and products of asteroidal collisions, represents the dominant source of
replenishmont of the interplanetary dust complex.