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Here's the answer, for planet Earth. A "solar day" is the time between the Sun's successive highest points in the sky. Astronomers refer to these peaks as "culminations".
There is some natural variation in the length of this "day". However, clocks use the "mean solar day". This is an average of the solar day lengths during a year and is indeed exactly 24 hours.
A "sidereal day" is the period from when a particular star reaches its peak until the next night when the same star reaches its peak again. This is 23 hours 56 minutes (and a few seconds).
So, the gap is just less than 4 minutes.
The difference is caused by the fact that the Earth is continuing along in its orbit while it is spinning. After precisely one rotation, or one sidereal day, we find that the Sun is still a few minutes away from reaching its peak, and it takes the Earth another 4 minutes or so to turn enough so that the Sun is once again at
its highest point in the sky.
What else can I help you with?
Why do we use the mean solar day rather then the sidereal day to measure the time for one earth rotation?
We don't. The sidereal day IS used as the measure of the Earth's rotation. The mean solar day is used to regulate our daily lives because that's the average time for the Sun to complete its apparent daily journey round the sky. The difference is because the solar day takes into account the effect of the Earth's orbital motion which slightly alters the position of the Sun in the sky.
What is the length of a day for all of the planet to planet?
There are two main definitions of "day" for a planet:1) Sidereal day. That's the time taken to rotate once.2) Solar day. That's the time taken for the Sun to complete one apparent journeyaround the sky. Usually it's given as the "mean solar day", which is the average value.The solar day depends on the planet's orbital motion, as well as its rotation.Here are the details, with slight approximations:Mercury : sidereal day, 58.65 Earth dayssolar day, 175.94 Earth daysVenus: sidereal day, 243.02 Earth dayssolar day, 116.75 Earth daysEarth: sidereal day, 23.934 hourssolar day, 24.000 hoursMars: sidereal day, 24.623 hourssolar day, 24.660 hoursFor these planets both days are nearly the same length:Jupiter: 9.92 hoursSaturn: 10.66 hoursUranus: 17.24 hoursNeptune: 16.11 hours
Is a sidereal day longer or shorter than a solar day?
The Sun crosses the meridian (the imaginaryline in the sky from due north to due south and passing directly overhead) at solar noon. The period between two successive solar noons is a "solar day". When you reckon the period of time between two successive meridian transits of a distant star, or the vernal equinox, that is a "sidereal day". In simple terms the sidereal day is the rotation period of a planet.
How many earth days equal one sidereal day on venus?
The sidereal day is the time it takes for a planet to rotate once. For Venus that's about 243 of our Earth days.
What would cause the solar day to be shorter than the sidereal day?
The sidereal day of a planet is the time it takes to rotate once on it's axis. The solar day is the time from sunrise to sunset. To see why they are different, let's image a planet that rotates very slowly. Every time it goes around its star once, it also rotates once on its axis. Since it rotates once on its axis per year, there is one sidereal day per year. Now, in order for this to work, one side of the planet must be facing the star at all times. This means that there is no sunrise or sunset, so on this planet, there are zero solar days in a year. Now let's image a planet that rotates twice a year (has two sidereal days a year). At the beginning of the year, a side of that planet is facing the star. Halfway through that year, the planet has rotates once, but is on the other side of the star, so that side of the planet is now facing away from the star. At the end of the year, the planet is back where it started. There has been one sunrise and one sunset, so only one solar day. From this we can see that a planet (as long as it has at least one sidereal day per year) has one more sidereal day per year than solar day per year. There are 365.242 solar days in an Earth year, but there are 366.242 sidereal days in an Earth year.
The fact that the Earth has moved along its orbit in the time it took to rotate once is the reason for?
the difference between a solar day (based on the position of the Sun) and a sidereal day (based on the position of the stars). Because the Earth has moved in its orbit, it needs to rotate a little longer to bring the Sun back to the same position in the sky each day.
Why do we use the mean solar day rather then the sidereal day to measure the time for one earth rotation?
We don't. The sidereal day IS used as the measure of the Earth's rotation. The mean solar day is used to regulate our daily lives because that's the average time for the Sun to complete its apparent daily journey round the sky. The difference is because the solar day takes into account the effect of the Earth's orbital motion which slightly alters the position of the Sun in the sky.
What is equation of time?
the distance between the solar time i.e Mean time apparent solar time is stated as equation of time. M.t-A.t=equation of time
What is the length of a day for all of the planet to planet?
There are two main definitions of "day" for a planet:1) Sidereal day. That's the time taken to rotate once.2) Solar day. That's the time taken for the Sun to complete one apparent journeyaround the sky. Usually it's given as the "mean solar day", which is the average value.The solar day depends on the planet's orbital motion, as well as its rotation.Here are the details, with slight approximations:Mercury : sidereal day, 58.65 Earth dayssolar day, 175.94 Earth daysVenus: sidereal day, 243.02 Earth dayssolar day, 116.75 Earth daysEarth: sidereal day, 23.934 hourssolar day, 24.000 hoursMars: sidereal day, 24.623 hourssolar day, 24.660 hoursFor these planets both days are nearly the same length:Jupiter: 9.92 hoursSaturn: 10.66 hoursUranus: 17.24 hoursNeptune: 16.11 hours
Is a sidereal day longer or shorter than a solar day?
The Sun crosses the meridian (the imaginaryline in the sky from due north to due south and passing directly overhead) at solar noon. The period between two successive solar noons is a "solar day". When you reckon the period of time between two successive meridian transits of a distant star, or the vernal equinox, that is a "sidereal day". In simple terms the sidereal day is the rotation period of a planet.
What is the relationship between apparent solar time and mean solar time?
The Earth "day" of exactly 24 hours is the "mean solar day""Mean" is basically a scientific way of saying "average". It's called a "solar day " because it's based on the position of the Sun in the sky.There are natural variations in the length of the solar day because of the Earth's elliptical orbit and axial tilt.The "mean solar day" averages out the variations that happen during the year.This makes things much more convenient for everyday life."Mean solar time" is based on the "mean solar day".The "apparent solar day" is the what we actually observe, and its length varies from day to day.A sundial measures "apparent solar time". We can convert this time to mean solar time by using something called "the equation of time".Actually, the sundial shows "local apparent solar time".That's because the time shown by a sundial depends on its exact longitude.For convenience, mean solar time has time zones (based on longitude).So, longitude also affects the relationship between these twomeasures of time.
Why is length of a sidereal day and a solar day on venus so different?
The sidereal day is about 243 Earth days. That is the time for the planet to rotate once . The solar day is 117 Earth days,roughly. That is a big difference. On Earth the difference between these two days is only about 4 minutes. The reason for the big difference on Venus is that Venus rotates very slowly. The solar day depends on the rotation of a planet AND its orbital motion. The slow rotation makes the effect of the orbital motion much greater on the length of the solar day. Incidentally Venus rotates in the opposite direction to Earth. That's why the solar day is shorter than the sidereal day. On Earth it's the other way round.
How many earth days equal one sidereal day on venus?
The sidereal day is the time it takes for a planet to rotate once. For Venus that's about 243 of our Earth days.
What would cause the solar day to be shorter than the sidereal day?
The sidereal day of a planet is the time it takes to rotate once on it's axis. The solar day is the time from sunrise to sunset. To see why they are different, let's image a planet that rotates very slowly. Every time it goes around its star once, it also rotates once on its axis. Since it rotates once on its axis per year, there is one sidereal day per year. Now, in order for this to work, one side of the planet must be facing the star at all times. This means that there is no sunrise or sunset, so on this planet, there are zero solar days in a year. Now let's image a planet that rotates twice a year (has two sidereal days a year). At the beginning of the year, a side of that planet is facing the star. Halfway through that year, the planet has rotates once, but is on the other side of the star, so that side of the planet is now facing away from the star. At the end of the year, the planet is back where it started. There has been one sunrise and one sunset, so only one solar day. From this we can see that a planet (as long as it has at least one sidereal day per year) has one more sidereal day per year than solar day per year. There are 365.242 solar days in an Earth year, but there are 366.242 sidereal days in an Earth year.
What is the difference between a sidereal month and and a synodic month?
A sidereal month is the time it takes the moon to complete one orbit of earth. A synodic month is longer than a sidereal month because it takes longer for the moon to go through it's phases
What is mean solar time called on the prime meridian?
Mean solar time on the prime meridian is known as Greenwich Mean Time (GMT).
What is the difference between a Sidereal month and lunar month?
A sidereal month is the time it takes the moon to circle the Earth with respect to the stars (27 days), A lunar month is the time it takes from full moon to full moon (29 days).
