64 Interesting Facts About Uranus

Last updated on February 2nd, 2024

Cold, windy Uranus looks like a planet on its side. But you can’t see Uranus. At least, it’s not visible to the naked eye even though it is the third-largest planet in our solar system (following Jupiter and Saturn) and four hundred times the size and 14.5 times the mass of the Earth. Uranus, together with Neptune, is considered an ice giant. Uranus’ blue colour is due to the methane in its atmosphere, which absorbs incoming red wavelengths and reflects the blue.

65 Interesting facts about Uranus, the oddball planet, that we bet will fascinate you

1. Uranus is too dim for ancient civilizations to have seen it. It is the seventh planet from the Sun (Order of the planets from the SunMercury, VenusEarthMarsJupiterSaturn, Uranus, Neptune, and Pluto (the dwarf planet)).

“Only one spacecraft has visited the planet – the Voyager 2 on January 24, 1986”

2. This is why there has been no mention of Uranus sightings before William Herschel saw it through his telescope in 1781. He had been surveying stars, including those that were ten times dimmer than visible stars.

3. When he looked through the telescope and saw a strange, slow-spinning object, Herschel wasn’t sure what he was looking at was a planet. The British astronomer thought it was a comet or a star. It took some time for others to confirm that Uranus was a planet because it follows a planetary orbit. 

4. In 1781, William Herschel, gave it the name “Georgium Sidus” after King George III. This naming was controversial in the astronomical society, and Uranus (Greek god father of Roman Saturn) was proposed in 1782 to follow the mythology so that it would not stand out from the other planets. This last proposed name started to be used worldwide in 1850.

5. The funny thing is this makes Uranus the first planet to have been discovered in modern times! Ancient people had already scanned the skies and discovered six of the nine planets that we recognize today (the other modern discoveries were Neptune and Pluto (now classified as a dwarf planet), too dim to the naked eye).

6. Although the name “Uranus” started to be used worldwide in 1850, the International Astronomical Union (IAU), which is the international authority for assigning designations to celestial bodies, officially used the name for the first time in its Resolution No. 10, which was approved by the XVIth General Assembly of the IAU in 1976.

“Uranus orbits the Sun every 84 Earth years.”

7. Uranus was formed about 4.5 billion years ago, closer to the Sun, and reached its final and current position 4 billion years ago.

8. Uranus is named after a Greek god, not Roman, like other planets.

9. If you love studying planets, you’ll know that most planets are named after Roman gods. Mars is the Roman god of war, for instance. The name Uranus refers to the Greek god Uranus, the god of the sky, father of Cronus (Saturn in Roman) and grandfather of Zeus (Jupiter in Roman), who is in turn father of Ares (Mars in Roman), Aphrodite (Venus in Roman) and Hermes (Mercury in Roman).

10. A lot of other names had been rejected in the naming of Uranus. These included Hypercronius (which means ‘above Saturn’) and even the dreadful Georgium Sidus (meaning ‘The Georgian Planet’) with which Herschel wanted to flatter the then-King of England George III. Thankfully Herschel’s sycophantic attempts to name Uranus was not popular, or we wouldn’t have ‘your-anus’ in our midst anymore!

11. Uranus is approximately 19.8 astronomical units away from the Sun, that is, 19.8 times the distance between the Sun and the Earth.

12. Uranus (the 7th planet of the Solar System) is almost twice as far from the Sun as Saturn (the 6th planet of the Solar System).

“Uranus has 27 moons”

13. Uranus’ equatorial diameter is approximately 4 times wider than that of the Earth. It is 50,727 km/31,518 miles long.

14. Due to its fast rotation, Uranus is not a sphere, but an oblate spheroid. Its polar diameter is 2.3% shorter than the equatorial diameter.

15. During the orbit of Uranus around the Sun, while one pole is exposed to the Sun the other one is in complete darkness, and this continuous “day” lasts 21 Earth years. This is due to the unique angle of the planet’s equator with its orbit (97.7 degrees).

16. The tilt of Uranus may have been caused by a collision.

17. No planet other than Uranus has such a screwball way of spinning around the sun! The Earth, as we know, spins at an angle of 23 degrees. Jupiter is barely tilted at an angle of 3 degrees.

A shot of Uranus taken by Voyager 2
A shot of Uranus taken by Voyager 2. Image credit – NASA

18. There’s a high chance that the reason for Uranus’s lopsided spinning is the many collisions it has suffered. If you look at near-infrared views of the planet, you’ll be able to see faint rings around the sphere. This will show you how deep the planet’s tilt angle really is. Something really big – many times bigger than the earth – may have crashed into Uranus a long time ago and thrown the planet on its side.

19. Experts believe that this tilt was the result, literally, of several punches to the planet and not just one big collision. This may have happened at the beginning of the solar system when the moons of Uranus were still balls of gas. Such a discovery has somewhat changed the way we think about the formation of planets in our solar system.

20. The old theory was that Uranus, Neptune, and the Saturn and Jupiter cores were created by pulling in small floating objects from space around it. But there is evidence to suggest that Uranus suffered a collision at least twice. This means that maybe planets can be created by impact too.

21. Uranus is icy and burning hot, with extreme seasons.

22. If you look in the direction of Uranus through a telescope, you will see a bluish-greenish disk. The planet’s color comes from the 2 percent methane gas in its atmosphere, along with mostly hydrogen (83 percent) and some Helium (15 percent). Methane makes it aquamarine or cyan in color.

23. In fact, Uranus has a thick, smoggy atmosphere that becomes denser the deeper you go. For example, if you were to fall off your spacecraft over Uranus, you’d probably find yourself half-falling and half-swimming through the planet’s atmosphere. In the heart of the icy smog of the planet is rock that is about the size of the earth.

24. The pressure on the surface is around 1.3 times that of the earth and the gravity is about 0.9 times that of Earth. In other words, a 10 feet dunk on Earth would equate to an 11 feet dunk on Uranus.

“Titania is the largest moon of Uranus”

25. Temperatures are freezing -153 degrees C to -218 degrees C in the deeper troposphere where the clouds are. Compare with Earth temperatures, where the coldest it’s got in recent years was a record -93.2 degrees C in Antarctica in 2013.

26. Uranus has the coldest atmosphere in the solar system and it’s not hard to see why. It’s over 19 times further away from the sun than the Earth is! the temperature on the planet can get as low as -224 degrees Celsius.

27. The planet can get as hot as it gets cold. Where the sun’s radiation hits the planet’s outer atmosphere layers, temperatures can get as hot as 577 degrees C. The core may get as hot as 4,727 degrees (which is nothing to Jupiter’s 24,000 degrees C core). But the sun is far away from Uranus, so the furnace in the core of Uranus probably plays a much larger role in keeping the planet warm.

28. This kind of extreme temperature difference creates seasons as long as 20 years. This is easier to understand if you think about how large Uranus is.

29. Uranus is a giant planet. Wind speeds on giant planets can be as much as 15 times stronger than winds on Earth. Winds on Uranus can travel as fast as 560 miles per hour. The icy winds of Uranus can uproot trees, dislodge houses and do a lot more damage in seconds than we’ve seen on Earth. As a reference, the strongest hurricanes on Earth, which fall into category 5 of the Saffir-Simpson scale, have a wind speed of at least 252 km/h (157 mph).

30. It’s fun to know that the winds of Uranus only blow in very narrow layers that are a very small proportion of the planet’s atmosphere. What this means is, there’s probably not a lot of weather activity going on deeper into the giant planet of Uranus.

Moons of Uranus

Uranus and its moons.
Uranus and its moons. Image credit – NASA

31. Uranus has 27 moons, Jupiter has 67 while the Earth has just one. Uranus has third most moons in the solar system. The last of these 27 moons was discovered in 2003.

32. There’s a lot more to learn about fascinating Uranus and its five major rocky moons: Miranda, Titania, Ariel, Umbriel, and Oberon.

33. Titania is the largest moon of Uranus. It is about 1/3rd the size of Earth’s moon. It is made out of rock and ice. Its name comes from the Queen of the Fairies in A Midsummer Night’s Dream by William Shakespeare.

34. The brightest of the Uranus’ moon is Ariel while the darkest is Umbriel.

35. The name of other moons of Uranus are: Trinculo, Puck, Cordelia, Setebos, Desdemona, Ophelia, Portia, Sycorax, Bianca, Cressida, Cupid, Belinda, Caliban, Rosalind, Stephano, Juliet, Mab, Perdita, Prospero, Ferdinand, Francisco and Margaret.

36. Wondering who suggested the names of these moons? Interestingly, the names of all the 27 moons of Uranus are taken up from the work of Shakespeare and Alexander Pope.

37. There has been only one spacecraft to have visited the planet – the Voyager 2 on January 24, 1986. It’s to be hoped there will be a lot more! Most of the information available from Uranus comes from the probe Voyager 2, which flew past the planet in 1986. The data collected keeps being analysed providing new discoveries to this day.

38. While Uranus orbits around the Sun in 84 Earth years, the planet experiences 42 years of summer (sunlight) time and 42 years of winter (darkness) time.

“Uranus aided the discovery of Neptune”

39. The planet rotates at an average distance of approximately 2.9 billion km from the Sun. And the Earth is at a distance of 149,600,000 kilometers from the Sun. Neptune has the longest orbit of any known planet – 4.5 billion km from the Sun.

40. The intensity of sunlight on Uranus is 1/400 the intensity of sunlight on Earth.

41. In 1789, Martin Heinrich Klaproth, the discoverer of Uranium, named the element after Uranus. 

42. What amazes is the fact that Uranus does not generate any heat which is more than what it receives from the Sun. Neptune, however, which is almost similar in size of Uranus, emits 2.6 times the heat it receives from the Sun. Now, there are different theories that explain the inability of Uranus to emit the heat from its core.

43. Sunlight takes almost 2 hours and 40 minutes to reach Uranus, which is 20 times the time it takes to reach the Earth.

44. Uranus has 13 rings. The nine internal ones are narrow and dark grey, the following two are faint, and from the two outer rings, the outermost is blue and the next one is red The size of the bodies in the rings vary between 0.2 and 20 m in diameter. Saturn, on the other hand, has 12 rings that are the most extensive ring system of any planet of the solar system.

45. Uranus rotates on its side, it spins horizontally. 

46. Uranus revolves in its orbit at a speed of 6.6 km/sec while Mercury is the fastest planet in this regard at 47.87 km/sec. 

47. One day on Uranus spans 17 hours and 54 minutes. 

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