As a result, longer days and longer nights can be expected last much longer on the Red Planet. Something for future colonists to consider! Given the fact that it is the largest planet in the Solar System, one would expect that a day on Jupiter would last a long time. But as it turns out, a Jovian day is officially only 9 hours, 55 minutes and 30 seconds long, which means a single day is just over a third the length of an Earth day. This is due to the gas giant having a very rapid rotational speed, which is This rapid rotational speed is also one of the reasons the planet has such violent storms.
Note the use of the word officially. Since Jupiter is not a solid body, its upper atmosphere undergoes a different rate of rotation compared to its equator. Because of this, astronomers use three systems as frames of reference. System II applies at all latitudes north and south of these; its period is 9 hours, 55 minutes, and So if you could, theoretically, stand on the cloud tops of Jupiter or possibly on a floating platform in geosynchronous orbit , you would witness the sun rising an setting in the space of less than 10 hours from any latitude.
And in the space of a single Jovian year, the sun would rise and set a total of about 10, times. Despite its massive size, the planet has an estimated rotational velocity of 9. As such Saturn takes about 10 hours and 33 minutes to complete a single sidereal rotation, making a single day on Saturn less than half of what it is here on Earth.
And, also like Jupiter, Saturn takes its time orbiting the Sun. With an orbital period that is the equivalent of 10, System II covers all other Saturnian latitudes, excluding the north and south poles, and have been assigned a rotation period of 10 hr 38 min Using these various systems, scientists have obtained different data from Saturn over the years.
In , this was revised by researches at the Department of Earth, Planetary, and Space Sciences, UCLA, which resulted in the current estimate of 10 hours and 33 minutes. Much like with Jupiter, the problem of obtaining accurate measurements arises from the fact that, as a gas giant, parts of Saturn rotate faster than others.
If the magnetic field has any angle to the rotation pole, then the magnetic field sweeps around the planet like the beam of a lighthouse, and there's a pulsing to the radio emissions in time with the planet's rotation rate. Voyager precisely measured the day lengths of Jupiter 9h 55m When Cassini got to Saturn, it also measured Saturn's rotation rate from its radio emissions. That's Saturn didn't slow down between Voyager in and Cassini in ; there is no force in the solar system that could have made such a massive planet slow its rotation so much, so rapidly.
One -- or both -- of the measurements was wrong. Later on in the Cassini mission, the team realized that their data showed different rotation rates in the northern and southern hemispheres!
Clearly, the method of using radio emissions to measure Saturn's rotation rate did not work the way it did at other giant planets. They are measuring something rotating, but it's not the bulk rotation of the planet. The Cassini magnetometer and radio and plasma wave science teams spent the rest of the mission trying to find a signal in their data that accurately represented the rotation rate of Saturn.
They were working on lots of other science too, and were very successful, but they failed to solve the problem of its rotation rate. Not for lack of trying and they're still trying , but just because the universe just doesn't work the way we thought it did, and the apparently simple question about the length of Saturn's day remains to be answered with other methods.
It approaches Saturn's rotation rate in a very different way, using ring seismology. Some wave structures in Saturn's rings are sensitive to the gravity field of Saturn. Gravity is a powerful way to investigate the deep interior of a planet. Their number, 10 hours, I will try to explain ring seismology, but it's not easy. The particles in the rings, researchers surmised, would register those tiny changes in the tug of gravity as wave pattern, which could then be used to determine how quickly the planet rotates.
The rings held the answer. When the Voyager probes flew past Saturn in and , researchers used magnetic field readings to estimate a day length of 10 hours, 39 minutes and 23 seconds. Mercury is gravitationally locked with the Sun in such a way that it rotates three times on its axis for every two times it goes around the Sun. If people could live on Mercury, they'd experience one full day sunrise to sunrise every two Mercurian years. Planet Venus spins so slowly on its axis that one day on the planet lasts nearly Earth days.
Because it's closer to the Sun than Earth is, the planet has a day year. So, the day is actually longer than a year, which means that Venus residents would only get to see two sunrises per year. One more fact to remember: Venus spins "backward" on its axis compared to Earth, which means those two yearly sunrises take place in the west and sunsets occur in the east. At 24 hours and 37 minutes, the Mars day length is very similar to Earth's, which is one of the reasons that Mars is often thought of as something of a twin to Earth.
Because Mars is farther than Earth from the Sun, however, its year is longer than Earth's at Earth days. When it comes to gas giant worlds, "day length" is a more difficult thing to determine. The outer worlds don't have solid surfaces, although they do have solid cores covered with huge layers of clouds and layers of liquid metallic hydrogen and helium beneath the clouds.
On the gas giant planet Jupiter , the equatorial region of the cloud belts rotates at a rate of nine hours and 56 minutes, while the poles rotate quite a bit faster, at nine hours and 50 minutes.
The "canonical" that is, commonly accepted day length on Jupiter is determined by the rotation rate of its magnetic field, which is nine hours, 55 minutes long. Based on measurements of various parts of gas giant Saturn including its cloud layers and magnetic field by the Cassini spacecraft, planetary scientists determined that the official length of Saturn's day is ten hours and 33 minutes.
Uranus is a weird world in many ways. The most unusual thing about Uranus is that it's tipped over on its side, and "rolls" around the Sun on its side. That means one axis or the other is pointed at the Sun during part of its year orbit.
The planet does rotate on its axis once every 17 hours and 14 minutes.
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