MAJOR MOONS OF NEPTUNE URANUS By Rolando Aguinaga
MAJOR MOONS OF NEPTUNE & URANUS By Rolando Aguinaga
TRITON • Triton moves around Neptune opposite to the planet’s rotation and movement around the Sun, but synchronous, i. e. , the same side of Triton always faces Neptune • The diameter of Triton is 2, 705 km, 3/4 the size of our Moon • It was probably captured, just like Pluto • Its surface is made of solid methane (CH 4) and N 2, with T = - 400° F • Its pinkish color is due to organic compounds that formed from CH 4 and N 2 • The density = 2. 1 g/cm 2, hence, there must be ices present • The albedo is very high, 0. 80 and, hence, the moon is bright • Triton surface is made of?
NEREID • Nereid is 340 km in diameter. • It has the most eccentric orbit of any moon in the Solar System. • Separation from Neptune varies from 1. 4 to 9. 6 million km • Its albedo is low, 0. 15, so Nereid is dark like our Moon • Nereid diameter?
MIRANDA • Miranda is about half water ice and half rocky material. • Miranda's surface is all mixed up with heavily cratered terrain intermixed with weird grooves, valleys and cliffs • It was initially thought that Miranda had been completely shattered and reassembled several times in its history, each time burying some parts of the original surface and exposing some of the interior. • Now a more mundane explanation involving the upwelling of partially melted ices seems to be in favor. • What was the original theory of why Miranda looks like it does?
ARIEL • The composition of Ariel is mostly water-ice and rock, together with some tholins. • Ariel’s interior consists of a rock inner core surrounded by a mantle of ice. • The surface of Ariel is extensively cratered and cut by scarps, canyons and ridges. Canyon widths range between 10 and 100 km, while their depths vary between 3 and 4 km. • There are signs of tectonic activity such as cry volcanism • There is evidence of carbon dioxide on the trailing hemisphere. Ariel has no detectable atmosphere or magnetic field, but there are signs of erosion on its surface. • The same hemisphere of Ariel always faces Uranus. Along with Uranus and its other satellites, Ariel takes 84 Earth years to orbit the sun. • What type of tectonic activity is there on Ariel?
TITANIA • The composition of Titania seems to be equal proportions of water-ice and non-ice components. • Titania may have a core of rock enveloped by an ice mantle. The core and mantle may be separated by a level of water some 50 km in thickness. • The surface of the moon is red with blue patches. It is heavily cratered and the largest crater, Gertrude, has a diameter of 360 km. • Canyons can be 50 to 100 km wide. • Astronomers believe that it has lost large amounts of carbon dioxide over its lifetime of 4. 6 billion Earth years. • Titania orbits synchronously around Uranus synchronously over an orbital period of 8. 7 Earth days, Titania takes 84 Earth years to orbit the sun. • How long does it take to orbit the sun?
- Slides: 6