Earth rotates once in about 24 hours with respect to the sun and once every 23 hours, 56 minutes and 4 seconds with respect to the stars (see below). Earth 's rotation is slowing slightly with time; thus, a day was shorter in the past. This is due to the tidal effects the Moon has on Earth 's rotation. Atomic clocks show that a modern - day is longer by about 1.7 milliseconds than a century ago, slowly increasing the rate at which UTC is adjusted by leap seconds. Analysis of historical astronomical records shows a slowing trend of 2.3 milliseconds per century since the 8th century BCE.
time it takes for earth to rotate on its axis
about 24 hours with respect to the sun and once every 23 hours, 56 minutes and 4 seconds with respect to the stars