From Sun, Uranus is the 7th planet and is the 3rd gas giant to live in our Solar System. This planet is pretty unusual. Some say that the planet is not visible to naked eye, but it is.
The planet is so far from Earth that it appears as a star because of its dimness. There is another thing that makes people think of it as a star – ‘its extremely slow orbital speed’! Let us learn 25 interesting Uranus facts and find out what makes this planet so interesting.
Interesting Uranus Facts: 1-5
1. Uranus gets its name from Ouranos – a Greek sky deity. Among lords of heaven, Ouranus was the earliest of lords.
2. The planet was accidentally discovered in 1781 by Sir William Herschel – a British astronomer. He was actually in the process of observing stars that were 10 times dimmer than those that were bright and easily visible to naked eye.
Herschel found Uranus and thought it to be a star and considered it to be unusual. One year later it was discovered that the unusual star discovered by Herschel actually followed a planetary orbit.
3. Uranus had several names proposed for it. One of them was Minerva (Roman god of Wisdom). The other was Hypercronius (means above Saturn) and the third one was Herschel.
Herschel wanted to flatter England’s King George III and offered the name ‘Georgium Sidus’ which in simple English means ‘The Georgian Planet’. None of the proposed names were adopted and later it was Johann Bode, a German Astronomer who proposed the current name of the planet.
4. This planet has an unusual blue-green color. This color comes from methane which is present in abundance in hydrogen–helium atmosphere of the planet.
5. Uranus is often referred to as ice giant. Simple explanation for this name is that 80% of Uranus’ mass is made of a fluid mix of ammonia ice, methane ice and water ice.
Interesting Uranus Facts: 6-10
6. Hydrogen gives the maximum volume to the planet’s atmosphere and makes up 82.5% of the total mass. Helium takes up 15.2% and methane takes up 2.3%.
7. As far as the planet’s mass is considered, 25% is taken up by rocks, 5-15% is taken up by helium and hydrogen and 60-70% is taken by ice.
8. The mantle of Uranus is made of methane ice, water ice and ammonia ice. The core is made of magnesium silicate and iron.
9. This planet is pretty unusual in the sense that its tilt is extremely unusual. It is so much titled that the planet actually revolves around the sun on its side.
Put in simpler words, the planet’s axis points almost directly to the sun. Scientists say that this unusual tilt is because in earlier days of the planet (just after its formation), the planet collided with another planet-sized object.
10. Uranus’ unusual tilt is actually responsible for extreme seasons found on the planet. How extreme is it? The planet rotates or completes one spin in 17 hours and 14 minutes and completes one revolution around the sun in 84 Earth years.
Uranus follows almost a circular orbit. This means that the planet maintains almost equal distance from Sun always. Because of the whopping 82 degrees tilt axis of the planet, it experiences seasons that are 20-year-long with sun shining directly on each pole for 20 years.
Interesting Uranus Facts: 11- 15
11. Uranus has 27 moons. These moons are named after the magical spirits found in English Literature, especially in works of Pope and William Shakespeare.
The two largest moons of Uranus are Titania and Oberon. These were the two moons first discovered in 1787 by William Herschel. The next two moons known as Ariel and Umbriel were spotted by William Lassell.
12. Interestingly, Lassell was also the first person to identify a moon of Neptune.
13. The fifth moon of Uranus was discovered in 1948 and was named as Miranda.
14. In terms of density, Uranus is the second least densest planet to live in our Solar System. The first one is Saturn that density less than that of liquid water. The density of Uranus is 1.23 grams per cubic centimeter.
15. Uranus is 14.53 times as big as Earth. However, because of low density of Uranus, a person will only experience 89% of gravity on surface of Uranus as compared to that on Earth.
Interesting Uranus Facts: 16-20
16. Uranus seems to have a very boring atmosphere. It looks like a big blue orb. There are no colorful bands of storms as found on Saturn and Jupiter.
However, this is what we see using a normal telescope. When viewed in infrared spectrum, this planet will show cloud patterns and bands. The atmosphere of the planet has certain bright regions.
Some clouds seen in atmosphere of Uranus stay only for a few hours, but there are some that have been around since 1986 (that’s the year when Voyager flyby took place).
17. Uranus has rings! You read it right. This planet has rings. However, they are not as prominent as that of Saturn. In terms of drama, however, the rings of this blue planet are second most dramatic in solar system. The rings of Uranus are made of dark objects, and hence, they are not easily visible.
18. Rings of Uranus are narrow and are only a few kilometers wide. Some astronomers opine that these rings are young and are possibly relatively recent. The planet has 13 rings.
19. Uranus is bright enough to fit within the brightness scale of human eyes. With a magnitude of 5.3, the planet can be observed using a set of binoculars in a bright sky backdrop. However, against a darker backdrop, it will be very difficult to see this planet.
20. Uranus leads a pretty solitary life. Why so? This planet has been visited by humans only once. Having said that, a clarification needs to be given. Actually any human did not go there. It was Voyager 2 of NASA that performed a flyby in 1986 and reached as close as 81,000 kilometers from surface of Uranus.
Interesting Uranus Facts: 21-25
21. The mass of Uranus is 86,810,300,000,000,000 billion kg, which is 14.53 times greater than that of Earth.
22. The Equatorial and Polar diameters of the planet are 51,118 and 49,946 kilometers respectively.
23. The planet has an equatorial circumference of 159,354 kilometers and an orbit distance of 2,870,658,186 kilometers, which is 19.22 Astronomical Units.
24. This planet is actually the coldest planet in solar system with an atmospheric temperature of -224 degrees centigrade and surface temperature of -197 degrees centigrade. Methane haze covers the upper atmosphere of the planet.
25. The climatic conditions on Uranus are extreme. After long chilled winters when sunlight reaches the dark areas for the first time, the atmosphere gets heated up and this leads to behemoth spring storms. How big are they? About the size of entire North America!
Sources:
Additional Source: Tristan Guillot, “Interiors of Giant Planets Inside and Outside the Solar System.” Science Vol. 286 (5437), p. 72-77, October 1, 1999.