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How far is Venus from Earth? Venus gets pretty close, actually. The minimum distance from Venus to Earth is 38.2 million km, or 23.7 million miles.

This is the minimum number, though, when Venus and Earth are at their closest point. When they're at their closest point, Venus is said to be in inferior conjunction (Sun – Venus – Earth). This is when the two planets are only 38.2 million km apart. And then when Earth and Venus are on opposite sides of the (Venus – Sun – Earth), Venus is in superior conjunction – the distance is 261 million km.

Because Venus gets so close to Earth, and it reflects back so much of the light that it receives from the Sun, Venus is the third brightest object in the sky (after the Moon and the Sun). But when Venus is close, we're actually seeing most of the planet in shadow. The bright side is facing towards the Sun. We see Venus as a crescent, similar to the Moon. But even then it's still brighter than anything else but the Moon and the Sun.

We have written many articles about Venus for Universe Today. Here's an article about how Venus might have once had oceans and continents, and here's an article about lightning storms seen on Venus.

If you'd like more info on Venus, check out NASA's World Book on Venus, and the NASA/JPL Solar System Exploration Guide to Venus.

We have also recorded an episode of Astronomy Cast all about Venus. Listen here, Episode 50: Venus.

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Venus Distance from the Sun is 108,208,930 km.

This number is an average, however. Venus follows an elliptical orbit as it travels around the Sun. At its closest point, which astronomers call perihelion, Venus is only 107 million km. And then when it's at its most distant point, called aphelion, Venus gets out to 109 million km. The orbital eccentricity of Venus is 0.0068.

Astronomers use another method of measuring distance in the Solar System called astronomical units. 1 astronomical unit is the average distance from the Earth to the Sun; approximately 150 million km. And so we can measure Venus' distance from the Sun in astronomical units. At its closest point, Venus is 0.718 AU, and then at its most distant point, it measures 0.728 AU from the Sun. Its average distance from the Sun is 0.723 AU.

We have written many articles about Venus for Universe Today. Here's an article about how we might colonize Venus with floating cities, and another on how life on Venus could have been blown to Earth.

If you'd like more information on Venus, check out NASA's World Book on Venus. There's also some great information on the Venus Express mission homepage, which is currently orbiting Venus.

We have also recorded an entire episode of Astronomy Cast just about Venus. Listen here, Episode 50: Venus.

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Venus orbits closer to the Sun than Earth, and so it takes less time to orbit the Sun. In fact, Venus takes only 224.7 days to orbit the Sun. Compare this with the Earth, which takes 365.25 days to orbit the Sun. This means that a year on Venus lasts only 62% the length of a year on Earth.

Unlike most of the planets in the Solar System, Venus has almost no axial tilt. Furthermore, its orbit is one of the most circular in the Solar System. This adds up to the fact that Venus doesn't have seasons like the rest of the planet. Instead, the temperature of Venus is always 461° C, at all times, everywhere on the planet. This also occurs because of the thick carbon dioxide atmosphere which traps the heat from the Sun building up global temperatures so hot they could melt lead.

One interesting thing about Venus is that it actually rotates backwards from the rest of the planets. While the other planets turn counter-clockwise on their axis seen from above the northern pole, Venus turns clockwise. It's as if the planet has been turned completely upside down on its axis. Astronomers aren't sure why this happens, but it's possible that Venus was struck by a large planetoid early in its history. Or it might just be through gravitational interactions with the Sun.

We have written many articles about Venus for Universe Today. Here's an article about the atmosphere of Venus. And here's an article about how Venus once had a wet volcanic past.

If you'd like more information on Venus, check out NASA's World Book on Venus. And you should also check out NASA's Solar System Exploration Guide on Venus.

We have also recorded an episode of Astronomy Cast just about Venus. Listen here, Episode 50: Venus.

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Want a Venus photo. Here, have 5 of the coolest Venus photos we could find and take your pick.

This is a photo of Venus seen in ultraviolet. The photo was taken by NASA's Pioneer spacecraft, and shows the cloud structure in Venus. Seen in normal light, Venus looks more hazy and cloudy. The clouds are made of sulfuric acid, and produce a truly acid rain.

This is a photo of Venus captured by NASA's Magellan spacecraft. It was launched on May 4, 1989 and arrived at Venus on August 10th. Unlike previous missions, Magellan was equipped with a radar system that allowed it to see beneath the thick clouds that normally obscure Venus from view. It revealed a dry landscape complete with volcanoes, mountains and impact craters.

Here's a photo of Venus with the new moon. This is the kind of thing that you might see with your own eyes. That's because Venus is the 3rd brightest object in the sky after the Sun and the Moon. It's easy to spot, and you might think it's a really bright star if you didn't know what you were looking for.

You might be surprised to know that robotic spacecraft have actually landed on the surface of Venus. This is a photo captured by the Soviet Venera spacecraft. It survived descent through the atmosphere and survived on the surface of Venus long enough to send back a few images. With temperatures hot enough to melt lead, nothing can really last for long there.

This is an artist's impression of a volcano erupting on the surface of Venus. Scientists have discovered lots of regions with past volcanism on Venus, but they're not sure if there are still active volcanoes on Venus.

We have written many articles about Venus on Universe Today. Here's an article about how Venus might have had a wet volcanic past, and here's an article about the rotation of Venus.

If you want more information on Venus, or want another Venus photo, check out these sites from NASA. The first you should check out is NASA's World Book on Venus. And you should also check out the NASA/JPL Solar System Exploration Guide.

We have also recorded an entire episode of Astronomy Cast just about Venus. Listen here, Episode 50: Venus.

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Here are some Venus photos.

The first photo of Venus shows what the planet looks like below its thick clouds. NASA's Magellan spacecraft was equipped with a radar instrument that let it look right through the clouds on Venus to build up a detailed contour map of the planet's surface. In these maps, scientists uncovered volcanoes, impact craters, and evidence of ancient eruptions.

And if you could look at Venus with your own eyes, this is about what you'd see. The surface of Venus is obscured by thick clouds of sulfuric acid. And down beneath these clouds, the carbon dioxide atmosphere gets as thick as almost 100 times the pressure here on Earth.

And so you might be amazed to know that a series of probes from the Soviet Union actually reached the surface of Venus and sent photos back to Earth. The temperatures at the surface of Venus are hot enough to melt lead, so the spacecraft didn't survive for very long, but they showed a hellish world, with rocks and lava plains as far as the "eye" can see.

Here's a photo of an occultation of Venus. This is when the planet passes behind another object in space; in this case Venus went behind the Moon.

And if Venus didn't look hellish enough, here's an artist illustration of the surface of Venus. It shows the sulfuric acid clouds, the dim sunlight that actually reaches down to the planet, and the rock-strewn landscape. It would certainly be a hostile place to visit.

We have written many articles about Venus for Universe Today. Here's an article about Venus might have had oceans and continents in the past. And here's an article about whether Venus is the hottest planet.

If you'd like some more information on Venus, as well as some great Venus photos, check out these resources from NASA. The first is called the NASA World Book: Venus, and the second is the NASA/JPL Solar System Exploration Guide.

We have also recorded an entire episode of Astronomy Cast just about Venus. Listen to it here, Episode 50: Venus.

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Here are some amazing Venus images.

This image shows Venus as a bright star next to a nearly new moon. Venus is actually the 3rd brightest object in the sky (after the Sun and the Moon), so it's easy to see with the unaided eye. Just look to the West after sunset, or to the East before sunrise. If you see a really bright object with a steady light, that's probably Venus.

Seen from here on Earth, the planet Venus seems to go through phases like the Moon. When Galileo first pointed his rudimentary telescope at Venus, he used this fact to help confirm the Copernicus theory that the Earth and the rest of the planets orbit around the Sun.

Weather on Venus

This is an image of Venus taken in the ultraviolet spectrum. This reveals the thick clouds that obscure the surface of Venus. Astronomers used to think that the surface of Venus was tropical, with steady rains from the clouds. We now know that the clouds are made of sulfuric acid, and the temperatures on the surface of Venus are hot enough to melt lead.

This is an image of the surface of Venus taken by NASA's Magellan spacecraft. Magellan used its radar instruments to peer through the Venus cloud tops, to build up a radar map of the surface of Venus. Using these images, astronomers have discovered volcanoes, mountain ranges and impact craters on the surface of Venus.

This is an artist's illustration of how the atmosphere of Venus interacts with the Sun's solar wind. Astronomers think that the hydrogen in Venus' atmosphere was blown away by the solar wind. This is why Venus is so hot and dry.

We have written many articles about Venus for Universe Today. Here's an article about the atmosphere of Venus, and here's an article about how Venus might have been wet in the ancient past.

If you'd like more information on Venus, check out two sites from NASA. There's the NASA World Book on Venus, and the NASA/JPL Solar System Exploration Guide. They've got some great Venus images too.

We have also recorded an episode of Astronomy Cast just about Venus. Listen here, Episode 50: Venus.

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Everyone liked our last set of pictures of planet Venus, so here are some more Venus pictures.

This Venus picture shows the planet's cloud structure in ultraviolet wavelengths. In this picture, Venus is seen from below its southern pole. The oval feature at the southern pole is called the south polar vortex, and it stretches about 2000 km across, and it's about 30 Kelvin warmer than its surroundings.

Here's a beautiful image of the new moon and Venus. Venus is the brightest object in the sky (after the Moon and the Sun), and it's easy to spot with the unaided eye. Just look West after sunset, or East before sunrise, and you should be able to see it.

This is a real picture, taken from the surface of Venus by the Soviet Venera probe. During the space race, the Soviets sent a series of probes to land on the surface of Venus. Almost all of them were destroyed during decent, but a few actually landed and survived long enough to send back some images.

The next Venus picture was taken by NASA's Pioneer spacecraft. It went into orbit around Venus in 1978, returning many images of the planet shrouded in clouds.

This Venus picture was taken by NASA's Magellan spacecraft. It shows the surface of the Venus beneath the planet's thick clouds. Magellan used a radar system to penetrate through the clouds and build up a surface map of the planet.

We have written many articles about Venus for Universe Today. Here's an article about a possible mission to Venus, and how NASA's MESSENGER spacecraft flew past Venus.

And if you want more information about the planet, as well as some great Venus pictures, check out two sites from NASA: World Book Venus, and the Solar System Exploration Guide.

We have also recorded an entire episode of Astronomy Cast just about Venus. Listen here, Episode 50: Venus.

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Here are some nice images of Venus.

This first image of Venus was taken during a recent occultation of Venus behind the Moon. This is a time when the planet passed behind the Moon from our vantage point here on Earth. Venus appeared to disappear behind the Moon, and then reappeared a few hours later.

This is an image that shows what the surface of Venus looks like. The colors have been created on computer to distinguish between the different elevation levels. The clouds of Venus are so thick they obscure any view of the surface of the planet. Spacecraft, like NASA's Magellan mission, use radar to pierce through the clouds and "see" the ground below.

And if you could get down to the surface of Venus, this is what you would probably see. This image is an artist's impression of the Venus surface. You can see how there are thick clouds of sulfuric acid. Temperatures on the surface of Venus are hot enough to melt lead.

This is an image of Venus that shows the planet going across the surface of the Sun. This event is called a transit, and it only happens once every century or so. It actually happens in pairs, separated by 8 years. The last transit was in 2004, and the next one will be in 2012. And then there won't be any others for more than a century.

And this Venus image shows the planet in ultraviolet. With this wavelength, scientists are able to distinguish different features in the cloud structure.

We have written many articles about Venus here on Universe Today. Here's an article about how life on Venus could have been blown to Earth a long time ago, and in this story, Venus glows in the dark.

If you'd like more images of Venus, and some really good information, check out these sources from NASA. There's the NASA Worldbook on Venus, and the Solar System Exploration Guide.

We have also recorded an entire episode of Astronomy Cast just about Venus. Listen to it here, Episode 50: Venus.

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Here are some pictures of Venus.

The first picture of Venus shows how the planet is always shrouded in clouds. Astronomers used to think that Venus might have been a hot tropical world with rain. We now know that the thick atmosphere is made of carbon dioxide, and conditions on the surface are hellish, with temperatures hot enough to melt lead.

This is one of the few pictures ever taken of the surface of Venus. It was captured by one of the Soviet Venera probes. During the space race, the Soviet Union sent a series of spacecraft to take images of the surface of Venus. Most were destroyed as they entered the thick atmosphere, but a few successful missions did make it to the ground and returned pictures of Venus like this.

Aside from the Sun and the Moon, Venus is the brightest object in the sky. You can easily see Venus if it's up during the night. If you see an incredibly bright star towards the West after sunset, or to the East before sunrise, that's probably Venus. This image, captured by James W. Young shows Venus together with the new moon.

This is an artist's impression of what the surface of Venus might look like during a volcanic eruption. You can see the thick clouds and volcanic material pouring out of active vents. Science missions to Venus have identified hundreds of extinct and dormant volcanoes, so it's likely the planet still has active volcanism.

This picture of Venus is based on radar data captured by NASA's Magellan spacecraft. It used a radar that could penetrate the thick clouds surrounding Venus and reveal the planet beneath. This shows what the terrain on Venus looks like.

We have written many articles about Venus for Universe Today. Here's an article about how Venus might have had a wet past, and even continents and oceans.

If you'd like more information on Venus, as well as some great pictures of Venus, visit NASA's World Book on Venus, and the NASA/JPL Solar System Exploration Guide.

We have also recorded an entire episode of Astronomy Cast just about Venus. Listen here, Episode 50: Venus.

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Determining how many planets are in our Solar System can be a difficult task because of the traditionally ambiguous definition of a planet. Mercury, Mars, Venus, Jupiter, and Saturn can be seen with the naked eye so they have been known to exist for thousands of years. Uranus, Neptune, and Pluto were discovered in the 18th, 19th, and 20th centuries respectively. They were quickly accepted as planets. However, technology began to become more advanced in the latter half of the 20th century and scientists began discovering many more celestial objects. In 2005, an object – Eris – was discovered that would spark a controversy concerning what exactly constituted a planet. The International Astronomical Union issued a decision in 2006 on the definition of a planet. Pluto was then reduced to the status of a dwarf planet, which was a newly created classification.

Currently, we have eight planets in our Solar System: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.  Mercury is the closest planet to the Sun. Named after the Roman messenger of the gods, it is the quickest planet to orbit the Sun.

Venus is a paradox of sorts. A shining planet, it has been associated with love and beauty by many different cultures throughout history. However, this beautiful morning and evening star is also deadly. The same clouds in the atmosphere that cause it to shimmer are composed of toxic gases.

Earth is in the habitable zone, a hypothetical zone where the conditions are supposed to be conducive to life. Our planet is also the densest one in the Solar System due to its core, which is comprised mostly of iron.

Mars is famous in science fiction lore. This Red Planet, as it is also known, has been the center of the search for life on other planets. Mars is actually only about half the size of the Earth with 15% of the Earth's volume.

Jupiter is the largest and most massive planet in our Solar System by far. The gas giant can fit over 1300 Earths inside. Jupiter has 63 moons that have been discovered so far.

Saturn is a gas giant with the lowest density of all the planets in the Solar System. It was named after the Roman god of agriculture most likely because it is the color of wheat.

Like the other gas giants, Uranus does not have a solid surface. Because the planet actually rotates on its side, it spends 42 years in darkness and 42 years in light – at least the poles do, but the equator actually experiences a short day and night cycle – before repeating the cycle.

Neptune is the final planet in our Solar System; its name after the Roman god of the sea, probably due to the planet's blue color caused by the methane in its atmosphere.

Universe Today has many articles on the planets including planets in the Solar System and 8 planets.

For more information, you should take a look at planets and all about the planets.

Astronomy Cast has episodes on each planet including Venus.

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Venus is also known as the evening star. It was given that name by ancient civilizations, such as the Greeks and Egyptians, who saw it in the sky. The planet was eventually named after the Roman goddess of love because of its beauty. Many ancient cultures have his planet with love and womanhood. Venus has been an important object in a number of different cultures including to the Babylonians and Mayans. The Mayans even used the movement of the planet to help create their complex calendar.

Venus is close to the Earth as well as the Sun. As soon as the Sun sets and it gets dark enough, Venus can often be seen in the sky. Because it seems In addition to being known as the evening star, Venus was also called the morning star because it could be seen for a few hours before the Sun grew too bright. The planet actually becomes brightest before the Sun rises or just after sunset. The ancient civilizations thought that the morning star and the evening star were separate celestial bodies. Pythagoras, the famous Greek mathematician, is believed to be the first person to realize that the morning and evening stars were actually the same object – Venus.

The Egyptians had two names for the planets because they thought it was actually two stars. The morning star was called Tioumoutri, and the evening star was known as Ouaiti. The Greeks called the evenings star Hesperos, the “star of the evening.” The Greeks called the morning star, Phosphoros “the Bringer of Light,” or Eosphoros, “the Bringer of Dawn.”

 Besides the Sun and Earth’s Moon, Venus is the brightest object in our Solar System. Its brightness is caused in part by the clouds of toxic gases that comprise its atmosphere. The sulfur dioxide and other elements in these clouds reflect light from the Sun causing the planet to shine.

Long after astronomers discovered that Venus was no longer the evening or morning star it has captivated the imagination of many. The swirling clouds that hid the surface of this shining planet from view were thought to shield a tropical paradise. Ironically, what many considered to be the most beautiful planet turned out to be a burning wasteland – the hottest planet in our Solar System. Another one of Venus’ many names is Earth’s twin because it is similar in size and mass to our own planet.

Universe Today has articles on the morning and evening star and the history of Venus.

For more information, you should take a look at Venus and an introduction to Venus.

Astronomy Cast has an episode on Venus.

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Many children dream of being astronauts or are simply fascinated by outer space. The planets are not just for scientists and other adults. If you have a little astronaut or are looking for resources, try some of these.

Mercury is the closest planet to the Sun and the smallest planet in our Solar System. If you are looking for more information, check out Mercury at Kids Astronomy and facts about Mercury.

Venus is the hottest planet in our Solar System and was named after the Roman goddess of love and beauty. Try Venus information for kids and Venus.

Earth is the densest planet in our Solar System. Find more fun facts about Earth at Geo Kids and Solar Views.

Jupiter is the largest planet in the Solar System and it also has the fastest rotation. If you want to learn more about Jupiter, try Kids Astronomy and the Lunar Outpost.

Saturn is the second largest planet in our Solar System, but it is most well known for its incredible planetary ring system. Check out Saturn and Saturn at Kids Astronomy.

Uranus  is the only planet to rotate on its side. You can find more information about Uranus at the World Almanac for kids and Uranus.

Neptune has the fastest winds of any planet in our Solar System. If you want to learn more about this planet, try the Lunar Outpost and the planet Neptune.

Universe Today has articles on the Solar System for kids and the Sun for kids.

If you are looking for more information, try an overview of the planets and NASA for students

Astronomy Cast has episodes on each planet, so check out Jupiter.

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A year on Earth is 365 days – unless it is a leap year – but the actual definition of a year is the time it takes a planet to orbit the Sun. Mercury orbits the Sun in 88 Earth days, which is the shortest orbit of any of the planets. This makes sense considering it is the closest object to the Sun. In comparison, a year on Mercury is about a quarter of a year on Earth. Mercury moves at different speeds depending on where it is in its orbit. When it is near its perihelion – the closest point to the Sun in an object’s orbit – it moves faster. It moves slower when it is near its aphelion – the farthest point from the Sun in an object’s orbit.

A year on Venus lasts 224.7 Earth days, which is 0.62 the length of a year on Earth. The odd thing about Venus is that a day on Venus is 243 days, so Venus’ day is longer than its year.

Earth’s year is actually 365.25 days long, not the 365 days that we round it to. Because an Earth year is not exactly 365 days, we have a leap year – a year with 366 days – every four years. That extra day is added to the month of February so in a leap year it has 29 days instead of 28. The next leap year is in 2012.

A year on Mars is 687 Earth days. You may have noticed by now that the length of the planet’s year increases the further the planet is from the Sun, which is only common sense because the further out planets have to make a bigger orbit around the Sun. Because two years on Earth is only a little more than a year on Mars, the two planets are close together every two years, which is when astronomers sends probes to Mars.

While it only takes about 10 hours for Jupiter to rotate, it takes 11.9 Earth years to orbit the Sun. Although this seems like a long time, it is actually much less than some of the other planets.

Saturn’s year is 29.7 Earth years long. Our planet rotates 30 times in the time it takes Saturn to rotate once.

A year on Uranus lasts 84.3 Earth years. One of the odd things about Uranus is that its axial tilt is so radical (97.8°) that it actually rotates on its side. This results in extreme seasonal changes.

Since Pluto lost its status as a planet, Neptune has the longest year. It takes the planet 164.8 Earth years to orbit the Sun. Our planet orbits the Sun almost 165 times before Neptune orbits it once, and we have not even seen an entire orbit since the planet was discovered.

Universe Today has articles on how long a year on Pluto is and orbits of the planets.

If you are looking for more information, try an overview of the planets and the planets.

Astronomy Cast has episodes on all the planets including Venus.

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One of the International Astronomical Union’s (IAU) requirements for a celestial body to be classified as a planet (or a dwarf planet) is that it orbits the Sun. All of the planets have different orbits, which affect many of the planets' other characteristics. Since Pluto became a dwarf planet, Mercury is the planet with the most eccentric orbit. The eccentricity of an orbit is the measurement of how different the orbit is from a circular shape. If an orbit is a perfect circle, its eccentricity is zero. As the orbit becomes more elliptical, the eccentricity increases. Mercury’s orbit ranges from 46 million kilometers from the Sun to 70 million kilometers from the Sun.

Venus, which is right next to Mercury, has the least eccentric orbit of any of the planet in the Solar System. Its orbit ranges between 107 million km and 109 million km from the Sun and has an eccentricity of .007 giving it a nearly perfect circle for its orbit.

Earth also has a relatively circular orbit with an eccentricity of .017. Earth has a perihelion of 147 million kilometers; the perihelion is the closest point to the Sun in an object’s orbit. Our planet has an aphelion of 152 million kilometers. An aphelion is the furthest point from the Sun in an object's orbit.

Mars has one of the most eccentric orbits in our Solar System at .093. Its perihelion is 207 million kilometers, and it has an aphelion of 249 million kilometers.

Jupiter has a perihelion of 741 million kilometers and an aphelion of 778 million kilometers. Its eccentricity is .048. Jupiter takes 11.86 years to orbit the Sun. Although this seems a long time compared to the time our own planet takes to orbit, it is only a fraction of the time of some of the other planets’ orbits.

Saturn is 1.35 billion kilometers at its perihelion and 1.51 billion kilometers from the Sun at its furthest point. It has an eccentricity of .056. Since it was first discovered in 1610, Saturn has only orbited the Sun 13 times because it takes 29.7 years to orbit once.

Uranus is 2.75 billion miles from the Sun at its closest point and 3 billion miles from the Sun at its aphelion. It has an eccentricity of .047 and takes 84.3 years to orbit the Sun. Uranus has such an extreme axial tilt (97.8°) that rotates on its side. This causes radical changes in seasons.

Neptune is the furthest planet from the Sun with a perihelion of 4.45 billion kilometers and an aphelion of 4.55 billion kilometers. It has an eccentricity of .009, which is almost as low as Venus' eccentricity. It takes Neptune 164.8 years to orbit the Sun.

Universe Today has articles on orbits of the planets and asteroid orbits.

For more information, check out articles on an overview of the Solar System and new planet orbits backwards.

Astronomy Cast has episodes on all the planets including Mercury.

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We are accustomed to thinking of a day as a period of 24 hours. However, that definition is a narrow one that only applies to our own planet. A day is the length of time it takes for a planet to complete one rotation on its axis – 360°. Since all of the planets rotate at different speeds, the length of a day on each one differs.

Compared to Earth, Mercury has a very long day. A day on Mercury takes 58 days and 15 hours in Earth days. A day on Mercury is only a little shorter than a year on the planet.

Venus is the slowest moving planet. In fact, it is so slow that while the other planets have flattened out at the poles due to the speed at which they spin, Venus has not flattened. Venus has the longest day of any planet in our Solar System. A day on Venus is 243 Earth days. Venus’ day is actually longer than its year. It only takes 224.7 Earth days for the planet to orbit the Sun.

We measure a day on Earth as a period of 24 hours, but it actually takes the planet 23 hours 56 minutes and 4 seconds to rotate on its axis. This measurement is actually called a sidereal day and is the length of time it takes the Earth to come back to the same position relative to the stars. While it seems that we would lose 4 minutes every day, that does not happen because the Earth is also orbiting the Sun.

A day on Mars takes 24 hours 39 minutes and 35 seconds in Earth time. The length of a day is similar to a day on Earth, which is one reason why scientists believed that plants and animals could survive on the Red Planet.

Jupiter is the largest planet, and it also has the shortest day. It takes Jupiter only 9.9 Earth hours to complete a rotation. Because the planet spins so quickly, it is extremely flattened at the poles and bulges out at the equator. The diameter of the equator is 9,300 km bigger than the diameter of the planet’s poles.

The length of a day on Saturn is extremely difficult to determine. It is always harder to determine the length of a day of a gas giant than it is to determine the length of a day of a terrestrial planet. Saturn’s day was measured at 10 hours 39 minutes and 24 seconds in the ‘80s. Then it was measured at approximately 10 hours 45 minutes and 45 seconds. In 2006, astronomers used more advanced equipment to measure the planets ending up with a measurement of about 10 hours and 47 minutes. Some astronomers believe that we will never know how long a day on Saturn is.

A day on Uranus only takes 17 hours 14 minutes and 24 seconds. Since the planet has such an extreme axial tilt (97.8°), it actually rotates on its side.

A day on Neptune lasts 16 hours 6 minutes and 36 seconds in Earth time. One odd thing about Neptune is that different parts of the planet rotate at different speed because the planet is mostly gas. The equator takes a couple more hours to rotate than the average while the poles rotate in about 12 hours.

Universe Today has articles on the rotation of Venus and how long a day on Jupiter is.

If you are looking for more information, try how long a day on Saturn is and all about the planets.

Astronomy Cast has episodes on all the planets including Mercury.

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