Earth orbits the sun approximately 365 days, 5 hours, 48 minutes, and 46 seconds, which we call a solar year. Which typically rounds the number of days in a calendar year to 365.

A solar year takes time for the Sun to travel from and return to the vernal equinox.

A sidereal year is 365 days, 6 hours, 9 minutes, and 10 seconds.

What’s the difference between a solar year and a sidereal year?

A solar year is the time it takes for the Earth to go around the Sun once, and a sidereal year is a time it takes for the Earth to go around once concerning the background stars. The sidereal year is slightly longer than the solar year because of the Earth’s elliptical orbit and the precession of the equinoxes.

What does a sidereal year measure?

There are two types of years- tropical and sidereal years.

The time it takes for the tilt of the Earth’s axis to return to the same angle relative to the sun is called a tropical year. Or the time before we come back and see the same stars rising behind the sun is called a sidereal year.

The equinox moves slowly in the opposite direction from Earth’s orbit around the sun, so the tropical year is 20.4 minutes shorter.

The Earth’s orbit

Our planet, Earth, travels in a slightly flattened circular path called an orbit around the Sun. It takes one year (365¼ days) for the Earth to complete one orbit. The Earth completes one orbit every 365.242199 mean solar days, which goes a long way toward explaining why we need an extra day, or leap year, every 4 years.

On Earth, we’re fairly close to the Sun, at some 150 million km (93 million miles). Earth’s orbit around the Sun takes us about 225 million km away from the Sun at our farthest point (known as aphelion) and about 147 million km at our closest (perihelion).

Source: skyatnightmagazine

Why does it take 365.24 days to go around the sun?

It takes 365.24 days to go around the sun because the Earth’s orbit around the Sun is 365.24 days. A ‘day’ is the Earth spinning once on its axis. An Earth year is 365.24 days, or 8,765 hours, or 526,000 minutes, or 31.6 million seconds. This means that every 365-day year, we gain ¼ of a day (6 hrs), so every 4th year, we add an extra day.

This is because the Earth’s elliptical orbit is not a perfect circle. The time it takes for the Earth to go around the sun varies depending on where it is in orbit. It’s fastest when it’s closest to the sun (perihelion) and slowest when it’s farthest away (aphelion).

What are Leap years

The Earth takes 365 and 1/4 days to orbit the sun. That is why we have a leap year every 4 years when a day is added to February. The answer, as precisely as we can figure for 2016, is 365.242188931 days.

If we just had 365 days in the year every year, we’d be off by nearly 1/4 of a day. It takes Earth 365.242190 days to orbit the Sun, or 365 days 5 hours, 48 minutes, and 56 seconds. This “sidereal” year is slightly longer than the calendar year. We keep our calendar synchronized with the seasons by adding one extra day every four years.