WHICH FORMULA OF SPECIAL THEORY OF RELATIVITY IS TRUE?

The paper considers three formulas for calculating the observed time interval according to the readings of a clock moving towards the observer. The first formula follows from the Lorentz transformations of the special theory of relativity (STR), the second - from the STR relation for the Doppler effect, the third formula is given in an article published in the scientific journal "Uspekhi Fizicheskikh Nauk". It is shown that under the same conditions, with the speed of movement towards the observer equal to 0.99 of the speed of light, the formulas give different results, differing from each other by 100 and 709 times. The question is raised about the choice of the true formula. The relevance of the work is due to the fact that SRT is used in applied sciences, in particular in the development of global satellite navigation systems, rocket and space technology. It is shown that the use of SRT formulas can lead to errors in determining the observed time interval of clocks of satellite navigation systems of the order 1∙10^-05. Such an error in determining the time can lead to an error in determining the distance to the navigation satellite equal to 3000 m. The error in determining the location of GLONASS navigation receivers in the horizontal plane should not exceed 12 m, therefore, the errors in calculating the time intervals that SRT formulas lead to are certainly unacceptable. The use of erroneous formulas can lead not only to the erroneous operation of aviation and space technology in which these formulas are used, but also to catastrophic consequences.