solar time

Scientific  

1. Time based on the rotation of the Earth with respect to the Sun. Solar time units are slightly longer than sidereal units due to the continuous movement of the Earth along its orbital path. For example, by the time the Earth has completed one full rotation on its axis with respect to the fixed stars, it has also moved a short distance in its orbit and is oriented slightly differently to the Sun, so that it must turn slightly more on its axis to complete a full rotation with respect to the Sun.

2. ◆ The time it takes the Earth to rotate fully with respect to the Sun is called a solar day. The length of a solar day varies throughout the year due to variations in the Earth's orbital speed and other factors.

3. ◆ The average value of all solar days in the solar year is called a mean solar day; it is 24 hours long and by convention is measured from midnight to midnight.

4. ◆ A solar year is the period of time required for the Earth to make a complete orbit with respect to the Sun as measured from one vernal equinox to the next; it is equal to 365 days, 5 hours, 48 minutes, 45.51 seconds. A solar year is also called an astronomical year and a tropical year.

5. ◆ A solar month is one twelfth of a solar year, totaling 30 days, 10 hours, 29 minutes, 3.8 seconds.

6. Compare sidereal time

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Example Sentences

Human sleep patterns prefer to be in sync with “solar time,” he said, and standard time is closer to true solar time.

From Seattle Times

A: At the Ingenuity site on Mars, which is within an ancient crater named Jezero, it will be the middle of the day, about 12:30 p.m. local Mars solar time.

From Seattle Times

Calculating prayer times requires inputting the longitude and date into a formula called the equation of time, which determines solar time, according to Omar Al-Ejel, a computer science major at the University of Michigan who built a prayer time app in 2015 that he continues to update.

From Los Angeles Times

While we may need them to function in a global society, even time zones cause some people to live on a different time than “solar time,” the time of day calculated from the sun’s position in the sky.

From Salon

A particular time zone’s clock time is set most closely to the eastern edge of the time zone’s solar time.

From Salon