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Planet Uranus By: JoanaChantengco

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Page 1: Planet Uranus

Planet Uranus

By: JoanaChantengco

Page 2: Planet Uranus

Uranus is the seventh planet from the sun

Page 3: Planet Uranus

- 3rd largest planetary radius-4rth Largest planetary mass-similar composition to Neptune “ice giant’’

Page 4: Planet Uranus

Uranus atmosphere

-hydrogen-helium-contain more “ices” such as water ammonia and methane along with traces of other hydrocarbons.

-interior of Uranus is main composed of ices and rocks

Page 5: Planet Uranus

Moons of Uranus

Page 7: Planet Uranus

Uranian moons are divided into three groups:

-Thirteen inner moons,

 -five major moons

-nine irregular moons. 

Page 8: Planet Uranus

the inner moons are small dark bodies that share common properties and origins with the planet's rings.

The five major moons are massive enough to have achieved hydrostatic equilibrium, and four of them show signs of internally driven processes such as canyon formation and volcanism on their surfaces.

The irregular moons have elliptical and strongly inclined (mostly retrograde) orbits at great distances from the planet.

Page 9: Planet Uranus

William Herschel discovered the first two moons, Titania and Oberon, in 1787, 

the other three ellipsoidal moons were discovered in 1851 by William Lassell (Ariel and Umbriel)

in 1948 by Gerard Kuiper (Miranda).

These five have planetary mass, and so would be considered (dwarf) planets if they were in direct orbit about the Sun.

Page 10: Planet Uranus

The largest of these five, Titania, is 1,578 km in diameter and the eighth-largest moon in the Solar System, and about one-twentieth the mass of the Moon. 

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The remaining moons were discovered after 1985, either during the Voyager 2 flyby mission or with the aid of advanced Earth-based telescopes.

Page 12: Planet Uranus

The first two moons to be discovered were Titania and Oberon which were spotted by Sir William Herschel on January 11, 1787, 6years after he had discovered the planet itself.

the next two moons, Ariel and Umbriel, were discovered by William Lassell in 1851

Page 13: Planet Uranus

The Roman numbering scheme of Uranus's moons was in a state of flux for a considerable time, and publications hesitated between Herschel's designations(where Titania and Oberon are Uranus II and IV) 

William Lassell's (where they are sometimes I and II).

In 1852, Herschel's son John Herschel gave the four then-known moons their names.

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Gerard Kuiper at the McDonald Observatory discovered the smallest and the last of the five large, spherical moons, Miranda.

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the flyby of the Voyager 2 space probe in January 1986 led to the discovery of ten further inner moons.Perdita, was retroactively discovered in 1999 after studying old Voyager photographs.

Uranus was the last giant planet without any known irregular moons, but since 1997 nine distant irregular moons have been identified using ground-based telescopes.

Page 16: Planet Uranus

Two more small inner moons, Cupid and Mab, were discovered using the Hubble Space Telescope in 2003.

The moon Margaret was the last Uranian moon discovered as of 2012, and its details were published in October 2003.

Page 17: Planet Uranus

After Herschel discovered Titania and Oberon on January 11, 1787, he subsequently believed that he had observed four other moons:  2 on January 18 and February 9, 1790,and 2 more on February 28 and March 26, 1794. It was thus believed for many decades thereafter that Uranus had a system of six satellites, though the four latter moons were never confirmed by any other astronomer.

Spurious moons

Page 18: Planet Uranus

Lassell's observations of 1851, in which he discovered Ariel and Umbriel, however, failed to support Herschel's observations; Ariel and Umbriel, which Herschel certainly ought to have seen if he had seen any satellites beside Titania and Oberon, did not correspond to any of Herschel's four additional satellites in orbital characteristics. 

Page 19: Planet Uranus

Herschel's four spurious satellites were thought to have sidereal periods of :

5.89 days (interior to Titania), 10.96 days (between Titania and Oberon), 38.08 days, and 107.69 days (exterior to Oberon).

and the credit for the discovery of Ariel and Umbriel was given to Lassell.

Page 20: Planet Uranus

Naming of moonsThe first two Uranian moons, discovered in 1787, did not receive names until 1852, a year after two more moons had been discovered. The responsibility for naming was taken by John Herschel, (son of the discoverer of Uranus)

Herschel, instead of assigning names from Greek mythology, named the moons after magical spirits in English literature:

the fairies Oberon and Titania from William Shakespeare's A Midsummer Night's Dream,

Page 21: Planet Uranus

and the sylphs Ariel and Umbriel from Alexander Pope's The Rape of the Lock (Ariel is also a sprite in Shakespeare's The Tempest)

The reasoning was presumably that Uranus, as god of the sky and air, would be attended by spirits of the air.

the fifth moon, Miranda, was named by its discoverer Gerard Kuiper after a thoroughly mortal character in Shakespeare's The Tempest. 

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At first, the outermost moons were all named after characters from one play, The Tempest; but with Margaret being named from Much Ado About Nothing that trend has ended.

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The Rape of the Lock (a poem by Alexander Pope):Ariel, Umbriel, Belinda

Plays by William Shakespeare:A Midsummer Night's Dream: Titania, Oberon, PuckThe Tempest: (Ariel), Miranda, Caliban, Sycorax, Prospero, Setebos, Stephano, Trinculo, Francisco, FerdinandKing Lear: CordeliaHamlet: OpheliaThe Taming of the Shrew: Bianca

Page 25: Planet Uranus

 Inner moon and Rings of Uranus

As of 2008, Uranus is known to possess 13 inner moons.

Their orbits lie inside that of Miranda. All inner moons are intimately connected to the rings of Uranus, which probably resulted from the fragmentation of one or several small inner moons.

Page 26: Planet Uranus

The two innermost moons (Cordelia and Ophelia) serve as shepherds of Uranus's ε ring, whereas the small moon Mab is a source of Uranus's outermost μ ring.

Puck, at 162 km, is the largest of the inner moons of Uranus and the only one imaged by Voyager 2 

Puck and Mab are the 2 outermost inner satellites of Uranus. 

Page 27: Planet Uranus

All inner moons are dark objects;

-their geometrical albedo does not exceed 10%

-They are made of water ice contaminated with a dark material

The small inner moons constantly perturb each other. The system is chaotic and apparently unstable. Simulations show that the moons may perturb each other into crossing orbits, which may eventually result in collisions between the moons. Desdemona may collide with either Cressida or Juliet within the next 100 million years.

Page 28: Planet Uranus

Large moonsUranus has five major moons: Miranda, Ariel, Umbriel,Titania, and Oberon. 

They range in diameter from 472 km for Miranda to 1578 km for Titania.

Umbriel is the darkest moon,Ariel is the brightest. 

6.7 × 1019 kg (Miranda) to 3.5 × 1021 kg (Titania)—for comparison, the Moon has mass of 7.5 × 1022 kg.

Page 29: Planet Uranus

The major moons of Uranus are believed to have formed in the accretion disc, which existed around Uranus for some time after its formation or resulted from the large impact suffered by Uranus early in its history.

All major moons comprise approximately equal amounts rock and ice, except Miranda :which is made primarily of ice. (ammonia and carbon dioxide.)

Ariel appears to have the youngest surface with the fewest impact craters, while Umbriel's appears oldest.

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the major moons of Uranus are airless bodies. For instance, Titania was shown to possess no atmosphere at a pressure larger than 10–20 nanobar

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The major moons have almost exactly the same rotational axial tilt as Uranus's (their axes are parallel to that of Uranus) The Sun would appear to follow a circular path around Uranus's celestial pole in the sky, at the closest about 7 degrees from it.

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The five largest moons of Uranus compared at their proper relative sizes and brightnesses. From left to right (in order of increasing distance from Uranus): Miranda, Ariel, Umbriel, Titania, and Oberon

Page 33: Planet Uranus

Irregular moonsAs of 2005 Uranus is known to have nine irregular moons, which orbit it at a distance much greater than that of Oberon, the furthest of the large moons.

All the irregular moons are probably captured objects that were trapped by Uranus soon after its formation.

Page 34: Planet Uranus

The diagram illustrates the orbits of those irregular moons discovered so far. The moons above the X axis are prograde, those beneath are retrograde. The radius of the Uranus's Hill sphere is approximately 73 million km.

Uranus's irregular moons range in size from about 150 km (Sycorax) to 18 km (Trinculo).[2] Unlike Jupiter's irregulars, Uranus's show no correlation axis versus inclination.

Page 35: Planet Uranus

Margaret is the only known irregular prograde moon of Uranus

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1-13 inner moons14-18 inner moons19-23 and 25-27 irregular moons (retrograde)24 irregular moons (prograde)

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Order label Name Distance(000km)

Radius (km)

Mass (kg)

Date Discoverer

1. VI Cordelia 50 13 ? 1986 Voyager 2

2. VIIOphelia 54

16 ? 1986 Voyager 2

3. VIII Bianca 59 22 ? 1986 Voyager 2

4. IX Cressida 62 33 ? 1986 Voyager 2

5. X Desdemona 63 29 ? 1986 Voyager 2

6. XI Juliet 64 42 ? 1986 Voyager 2

7. XII Portia 66 55 ? 1986 Voyager 2

8. XIII Rosalind 70 27 ? 1986 Voyager 2

9. XXVI Cupid 75 6 ? 2003 Showalter

Page 38: Planet Uranus

Order Label Name Distance(000km)

Radius (km)

Mass (kg)

Date Discoverer

10. XIV Belinda 75 34 ? 1986 Voyager 2

11. XXV Perdita76

40 ? 1986 Voyager 2

12. XV Puck 86 77 ? 1985 Voyager 2

13. XXVI Mab 98 8 ? 2003 Showalter

14. V Miranda 130 266 6.30e19 1948 Kuiper

15. I Ariel 191 579 1.27e21 1851 Lassell

16. II Umbriel 266 585 1.27e21 1851 Lassell

17. III Titania 436 789 3.49e21 1787 Herschel

18. IV Oberon 583 761 3.03e21 1787 herschel

Page 39: Planet Uranus

Order Label Name Distance(000km)

Radius (km)

Mass (kg)

Date Discoverer

19. XXII Francisco 4281 6 ? 2003 Sheppard

20. XVI Caliban7169

40 ? 1997 Gladman

21. XX Stephano 7948 15 ? 1999 Gladman

22. XXI Trinculo 8578 5 ? 2001 Holman

23. XVII Sycorax 12213 80 ? 1997 Nicholson

24. XXIII Margaret 14689 6 ? 2003 Sheppard

25. XXIII Prospero 16568 20 ? 1999 Holman

26. XIX Setebos 17681 20 ? 1999 Kavelaars

27. XXIV Ferdinand 21000 6 ? 2003 Sheppard