- Diameter: 51,118 km
- Temperature: – 323 °F (- 197 °C)
- Mass: 8.7E25 kg
- Sun: 2,871,000,000 km from the Sun
- Position: 7th planet in our solar system
- Discovery: William Herschel in 1781
- Atmosphere Composition: 83% hydrogen, 15% helium
- Rings: 13
- Moons: 27
- Color: Cyan
- Name: Uranus Is Named after the Greek God Ouranus
- Time: Uranus Needs 84 Earth Years to Orbit the Sun
- Size: Uranus Is 63 Times Bigger and 15 Times Heavier than Earth
- Climate: Uranus Is the Coldest Planet in the Solar System
- Differences: Uranus Is Very Different from Earth
- Moons: Titania Is the Largest Moon of Uranus
- Structure: Uranus is Composed of Rocks, Water, Hydrogen, Helium, Ammonia and Methane
- Distance: Uranus Is Years Away from Earth
- Exploration: Only One Probe has Explored Uranus so Far
- Future: Uranus May Serve as a Mining Site for Helium-3 in the Future
- All 27 of Uranus’ Moons are Named for Characters from the Works of Shakespeare and Pope
- Uranus Is One of the Few Objects in Our Solar System with a Retrograde Rotation
- We Do Not Know Exactly What the 13 Uranus Rings Are Made From
- The Poles of Uranus Get 42 Years of Constant Sunlight and 42 Years of Constant Darkness
- The Winds of Uranus Can Reach Speeds Up to 560 mph
- The Chemical Element Uranium Is Named after the Planet Uranus
- Uranus Is 19 Times Farther from the Sun than Earth Is
- Holy Moly, Uranus Can Be Seen without a Telescope
- Uranus’ Largest Ring Is 10,500 Miles Wide
- Uranus Is the First Planet Discovered in the Modern Era
Uranus Is Named after the Greek God Ouranus
Uranus facts reveal that it is the only planet in our solar system named after a Greek god, although its initial name was different. When the planet was discovered in March 1781 by the German-British astronomer William Herschel, he named it Georgium Sidus (George’s Star) in honor of his patron King George III, the then monarch of Great Britain and Ireland.
But the name was not accepted internationally and soon other proposals for a name were given. Eventually, the proposal of German astronomer Johann Elert Bode to name the new planet after the old Greek god of the sky was accepted, using the Latinized version of the deity’s name.
Uranus Needs 84 Earth Years to Orbit the Sun
This means that one Uranus year is equivalent to 84 Earth years, or approximately 30,687 Earth days. But days on Uranus are not the same as on Earth – it takes Uranus 42,718 of its days to orbit the Sun since the days on Uranus are approximately 6 hours and 46 minutes shorter than days on Earth. Now, who can calculate their age is Uranian years?
Uranus Is 63 Times Bigger and 15 Times Heavier than Earth
Its surface is also 16 times bigger than the Earth’s and its radius is four times bigger than the Earth’s. To get a better grasp of its massive size, let us take a look at the numbers: radius approximately 25,500 km, surface area approximately 8,000,000,000 km2, volume approximately 68,000,000,000,000 km3 and mass approximately 87,000,000,000,000,000,000,000,000 kg.
Uranus Is the Coldest Planet in the Solar System
Uranus facts reveal that its climate is not very friendly. It is fairly calm, but very low temperatures, intense seasonal variations, limited atmospheric activity and violently strong winds make it very harsh by the standards of the Earth’s weather. Its conditions mean that Uranus is definitely not a top choice for the future expansion of the human race through space…
Uranus Is Very Different from Earth
In addition to all the differences in time measurement, and size and climate of Uranus and Earth, there are several other Uranus facts that reveal important differences between the two planets. Earth is a much denser planet, with Uranus reaching only about 23% of Earth’s density. Gravity on Uranus is also lower, reaching approximately 90% of Earth’s, and Uranus gets much less solar radiation energy than Earth – almost 400 times less.
Titania Is the Largest Moon of Uranus
Of the 27 moons around Uranus, 5 are considered to be major moons and Titania is the biggest of them all. Its radius is approximately 788 km (about one eighth of Earth’s) and its gravity is almost 30 times less than Earth’s. Titania got its name from William Shakespeare’s “A Midsummer Night’s Dream”, and was named after the queen of the fairies. The moon was discovered by the same man who discovered Uranus a few years earlier – William Herschel. It is the 8th largest moon in our solar system.
Uranus is Composed of Rocks, Water, Hydrogen, Helium, Ammonia and Methane
Uranus facts teach us that this planet’s structure has three layers: the rocky core of silicate and iron-nickel; the mantle, which contains water, ammonia and methane; and the atmosphere which is mostly composed of hydrogen and helium. Most of Uranus’ mass comes from water, ammonia and methane, followed by rocks in the core and the helium and hydrogen in the atmosphere.
Uranus Is Years Away from Earth
The constant motion of planets in the solar system means any distances between planets are always changing, but when Uranus is closest to Earth, the distance between them is 2.6 billion kilometers At its furthest, the distance is 3.2 billion kilometers. That means that light from the Earth can reach Uranus in slightly less than 2 and a half hours when the planets are nearest. But getting a spacecraft from Earth to Uranus would of course take much longer since we cannot travel with the speed of light – the journey would take nearly 10 years.
Only One Probe has Explored Uranus so Far
Considering the vast distance between our planet and Uranus, it is no big surprise that only once spacecraft has approached Uranus in the history of mankind. In 1986, the space probe Voyager 2 flew by Uranus at a distance of approximately 81,500 kilometers, providing us with the majority of data we have on Uranus to this very day.
No other spacecraft has visited Uranus since then, and no future missions to Uranus are confirmed at the moment, but quite a few have been proposed to occur in the next decade. A joint NASA and ESA mission to Uranus – Uranus Pathfinder – is proposed to be launched from Earth in 2022, and Johns Hopkins University proposed another mission that would launch in 2021 and reach Uranus 17 years later – the Herschel Orbital Reconnaissance of the Uranian System (HORUS).
Uranus May Serve as a Mining Site for Helium-3 in the Future
Helium-3 is a non-radioactive isotope of helium that is useful for nuclear fusion and the technologies connected with it (mostly energy and weapon production). Unfortunately, it is very rare on Earth, so it is possible that the human race will mine the isotope on other planets someday. All gas giants in our solar system are much richer with the isotope than Earth is, and Uranus has the lowest escape velocity of them all. This leads some scientists to predict that Uranus might be our first choice for mining when we finally develop the technology that would make this possible.
All 27 of Uranus’ Moons are Named for Characters from the Works of Shakespeare and Pope
Oberon, Titania, Umbriel, Ariel, Miranda, Puck, Perdita, Cupid, Mab, Margaret and others are all named after William Shakespeare’s and Alexander Pope’s characters. One of the moons, Ophelia, was named after a character in one of Shakespeare’s most famous plays, Hamlet. The names for the first moons discovered were chosen by the son of the man who discovered Uranus and its first moons, John Herschel, 30 years after his father had died.
Uranus Is One of the Few Objects in Our Solar System with a Retrograde Rotation
The retrograde rotation of objects in a solar system is defined as opposite to the rotation of the central object – the Sun. Most of the solar system’s planets, its satellites and other objects rotate in a prograde direction; Uranus and Venus are the only planets in our solar system which have a retrograde rotation.
We Do Not Know Exactly What the 13 Uranus Rings Are Made From
Uranus facts reveal that these rings are very dark and faint, which is also the reason that the first of them were only discovered in the late 20th century. Scientists do not currently know what matter these rings consist of, but they presume it is mostly water and ice in combination with an unknown dark radiation-created organic matter. There are currently known to be 13 rings in total, but these were discovered at different times.
The Poles of Uranus Get 42 Years of Constant Sunlight and 42 Years of Constant Darkness
One of the previous Uranus facts already revealed that Uranus needs 84 years to orbit the Sun, and due to its large axis tilt (98 degrees) it lies almost sideways when travelling around the Sun. This causes its poles to lie where the equator lies on Earth. This also means that one pole is directly exposed to sunlight for half of the planet’s orbital time, and the other lies in complete darkness during that period.
The Winds of Uranus Can Reach Speeds Up to 560 mph
For comparison: the winds on Earth can reach speeds up to 250 mph outside tornadoes, and up to around 300 mph inside tornadoes. Such winds are very extreme though, and are thankfully rare. Just as all winds on Earth are not as strong as the maximum speeds, it’s true that not all winds on Uranus reach speeds of over 500 mph. In fact, only winds between +/- 50°-60° latitude are that strong.
The Chemical Element Uranium Is Named after the Planet Uranus
Uranium was discovered in 1789 by the German chemist Martin Heinrich Klaproth, eight years after William Herschel had discovered the planet Uranus. Klaproth choose the name for his chemical element in order to honor the then newly discovered planet. Uranium has a wide range of industrial applications. One of the uses you’re probably most familiar with is its role in fueling nuclear power plants.
Uranus Is 19 Times Farther from the Sun than Earth Is
This is also the reason why Uranus gets much less sunlight than the Earth does and has considerably lower temperatures than we enjoy here. The fact that the distance between the Sun and Uranus is 19 astronomical units (AU) is of course no coincidence – 1 AU is defined as the distance between the Earth and the Sun (about 93 million miles).
Holy Moly, Uranus Can Be Seen without a Telescope
As surprising as this may seem, Uranus can indeed be observed from Earth without using a telescope, despite being so far away. Its magnitude of 5.3 is just within the brightness scale that the human eye can perceive. In order for us to actually see Uranus, however, the sky needs to be extremely dark and one needs to know where exactly in the sky to look. If you do want to be sure to see Uranus, binoculars or a telescope are still a great help, of course…
Uranus’ Largest Ring Is 10,500 Miles Wide
Mu (μ) ring, one of the two outside rings of Uranus, is the biggest of all 13 Uranus’ rings. This huge ring has an amazing width of 10,500 miles, or 17,000 km. To get a sense of the huge scale of the ring, we can compare it to distances we are familiar with here on Earth. Its width is greater than the distance between New York and Sydney, Australia, and more than four times the total distance between Los Angeles and New York…
Uranus Is the First Planet Discovered in the Modern Era
Discovered in the late 1700s, Uranus is the first of only two planets discovered in the modern era, and by using a telescope (the second is Neptune, discovered in the mid-1800s). All other five objects (excluding Earth) in our solar system that are considered to be planets were discovered long before that – by ancient Babylonian astronomers in the 2nd millennium BC. Pluto, which was discovered in 1930, was initially considered to be the 9th planet of our solar system, but was later classified as only a dwarf planet.
Uranus Facts — Facts about Planet Uranus Summary
Uranus is the 7th planet in our solar system, and lies between 2.6 and 3.2 billion kilometers away from Earth. It was the first planet that was discovered in the modern era. It is 63 times bigger and 15 times heavier than Earth, and its climate, atmosphere and composition are also very different from the Earth’s, so no life (at least, not as we know it on Earth) is possible on Uranus. Uranus has been seen up-close by mankind only once – through the Voyager 2 space probe that flew by the planet in 1986, but some believe that the planet could serve as a mining base for isotope Helium-3 sometime in the distant future.