Convert Second (s) to Month (Synodic) (month (synodic)) instantly.
About these units
Second (s)
The second is the fundamental SI unit of time and the basis for nearly every modern timing system, from everyday clocks to astronomical calculations and quantum physics. Historically, the second was defined as 1/86,400 of a mean solar day—reflecting Earth's rotation. But because Earth's rotation is not perfectly constant, this definition proved insufficient for scientific precision. Today, the second is defined by the vibration frequency of the cesium-133 atom, specifically 9,192,631,770 oscillations of its hyperfine transition. This atomic definition gives the second extraordinary accuracy and stability, enabling technologies like GPS, satellite communications, deep-space navigation, and particle physics experiments. The second sits at the intersection of human history and cutting-edge physics: once tied to the apparent motion of the Sun, it is now anchored to a universal atomic constant, making it one of the most precisely defined units in science.
Month (Synodic) (month (synodic))
A synodic month is the time the Moon takes to complete a full cycle of phases—from new moon to new moon—lasting about 29.53059 days. Unlike the simple geometric orbit of the Moon, the synodic period aligns with the Sun–Earth–Moon relationship, making it tied to how humans perceive the Moon's illumination cycle. This is the month that shaped nearly all ancient calendars, from Babylonian to Hebrew, Islamic, and Chinese systems. Religious festivals, agricultural cycles, and early navigation practices all relied on the regularity of the synodic month. Even today, while civil calendars use fixed months, astronomical calculations and lunar calendars still depend on synodic months to track tides, eclipse cycles, and the dynamics of Earth's only natural satellite. The synodic month illustrates how natural celestial rhythms guided early human civilization.