We use the currently most complete collection of reliable Cepheid positions (565 stars) out to ∼ 5 kpc based mostly on our photometric data to outline the spiral pattern of our Galaxy. We find the pitch-angle to be equal to 9-10 o with the most accurate estimate (i =9.5 ±0.1 o ) obtained assuming that the spiral pattern has a four-armed structure, and the solar phase angle in the spiral pattern to be χ ⊙ = 121 o ± 3 o . The pattern speed is found to be Ω sp = 25.2 ± 0.5 km/s/kpc based on a comparison of the positions of the spiral arms delineated by Cepheids and maser sources and the age difference between these objects.
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