To travel once around Earth’s orbit in a path around the Sun is a journey of 940 million kilometers. The extra 3 million kilometers that Earth travels through space, per day, ensures that rotating by 360 degrees on our axis won’t restore the Sun to the same relative position in the sky from day to day. This is why our day is longer than 23 hours and 56 minutes and 4.09 seconds, which is the time required for the spheroidal Earth to spin a full 360 degrees. Similarly, a “year” is not the time it takes for Earth to make a full 360 degree revolution around the Sun, but is determined by the return of its axis to the same position relative to the Sun to the year before.
To travel once around Earth’s orbit in a path around the Sun is a journey of 940 million kilometers. The extra 3 million kilometers that Earth travels through space, per day, ensures that rotating by 360 degrees on our axis won’t restore the Sun to the same relative position in the sky from day to day. This is why our day is longer than 23 hours and 56 minutes and 4.09 seconds, which is the time required for the spheroidal Earth to spin a full 360 degrees. Similarly, a “year” is not the time it takes for Earth to make a full 360 degree revolution around the Sun, but is determined by the return of its axis to the same position relative to the Sun to the year before.