Earthquakes can permanently shorten the length of the Earth’s day. If a strong enough Earthquake occurs, it can move the spin of the Earth’s axis. The 2011 Earthquake in Japan knocked 1.8 microseconds off our days according to researchers.
100 Mind-Blowing Axis Facts
We always see the same side of the moon. Although the moon has phases, we will only ever see one side of it. It rotates on its axis at the same time it orbits the Earth.
Venus is the only planet that rotates clockwise. Most planets rotate on their axis in an anti-clockwise motion. However, Venus rotates clockwise in retrograde once every 243 Earth days.
The tilt on the axis of Mars is 25 degrees which means that the planet experiences seasons like we do on Earth as different parts of the planet are closer to the sun at different times of its orbit.
Our days are getting longer. Earth’s spin speed is slowing: every year, it takes our planet a little longer to complete one full revolution on its axis. The change is miniscule, however. Every century, Earth slows by 1/500th of a second; 1,000 years from now, one day will be two-hundredths of a second longer than today.
Jupiter is the fastest-spinning planet in the solar system (it only takes about 10 hours to complete a full rotation on its axis).
Days on Venus are longer than years. Due to its slow axis rotation, it takes 243 Earth days to spin once; but it only takes 225 Earth days to go around the sun.
Science has several different ways of defining time. To cover just a couple: There’s astronomical time, which is measured by how long it takes Earth to rotate on its axis. In astronomical time, a second is 1/60th of a minute. And then there’s atomic time, which dictates the numbers that you’ll see on a clock. According to atomic time, one second equals 9,192,631,770 oscillations of a cesium-133 atom. Measuring the vibration of an atom—which, in simple terms, is the gist of what oscillation is—is the most accurate way to track time.
There are two ways to think of the length of a day on Earth. Though you probably learned that one day on Earth is 24 hours, it takes the planet 23 hours, 56 minutes, and 4.0916 seconds to rotate on its axis. This is the difference between a solar day and a sidereal day—a solar day is 24 hours, whereas a sidereal day is roughly four minutes shorter. We measure solar time based on the sun’s position in the sky; a sidereal day is measured based on the location of the “fixed” stars. In other words, a sidereal day is the time it takes for a distant star or constellation to appear on the same meridian.