Triton #6 Proto-Earth
November 13, 2012 in Science
Solar System Discovery Revealed: Importance of Action for Humanity
“With a diameter of 2,700 kilometers, Triton is the seventh largest moon in the Solar System and the sixteenth largest object in the Solar System. The satellite is larger than the dwarf planets Eris and Pluto. Triton is considered to be one of the coldest places in the Solar System. The moon is -235°C while Pluto averages about -229°C. Scientists say that Pluto may drop as low as -240°C at the furthest point from the Sun in its orbit, but it also gets much warmer closer to the Sun, giving it a higher average temperature than Triton.
Triton is unusual for several reasons, but one of the biggest is its retrograde orbit. The moon orbits Neptune backwards compared to the orbit of all the other moons. This means that Triton didn’t form in orbit around Neptune, but formed somewhere else and was captured later on by Neptune’s gravity. It’s possible that Triton was a Kuiper Belt Object that fell into Neptune’s gravity field. Or maybe Neptune stole it from another planet.
It is also one of the few moons that are geologically active, which means that its surface is relatively young due to its changing nature. Volcanoes have been discovered on the planet, but these eruptions are ammonia and water lava rather than the liquid rock found on Earth. Because of the geological activity which is constantly changing the moon’s surface, there are very few impact craters on Triton. Additionally, Triton has a slight atmosphere comprised mostly of nitrogen with some methane. Scientists believe the atmosphere is the result of nitrogen evaporating from the moon’s surface. The moon has a reddish tint, which is probably due to the methane ice turning to carbon due to exposure to ultraviolet radiation. Over half of the moon’s surface is covered with frozen nitrogen while frozen carbon dioxide and frozen water cover most of the remaining surface. There are also traces of other substances such as methane and carbon monoxide on the moon’s surface. Underneath the surface is a mantle comprised of ice, rock, and metal. This core is what makes the moon so dense.”
“There are very few craters visible; the surface is relatively young. Almost the entire southern hemisphere is covered with an “ice cap” of frozen nitrogen and methane (right).
There are extensive ridges and valleys in complex patterns all over Triton’s surface. These are probably the result of freezing/thawing cycles.
The most interesting (and totally unexpected) features of this unusually interesting world are the ice volcanoes. The eruptive material is probably liquid nitrogen, dust, or methane compounds from beneath the surface. One of Voyager’s images shows an actual plume rising 8 km above the surface and extending 140 km “downwind” (below).
Triton, Io and Venus are the only bodies in the solar system besides Earth that are known to be volcanically active at the present time (though Mars clearly was in the past). It’s also interesting to note that very different volcanic processes occur in the outer solar system. Earth’s and Venus’ (and Mars’) eruptions are of rocky material and are driven by internal heat. Io’s eruptions are probably sulfur or sulfur compounds driven by tidal interactions with Jupiter. Triton’s eruptions are of very volatile compounds like nitrogen or methane driven by seasonal heating from the Sun.”
Features of Triton
This close-up image of Triton was taken by the Voyager 2 spacecraft. The image clearly shows Triton’s diverse and mysterious surface features and terrain types. (NASA/JPL)
Statistics for Triton:
Discovered by ……. William Lassell
Year of Discovery ……. 1846
Diameter ……. 1,677 miles (2,700 km)
Mean Distance from Neptune ……. 220,405 miles (354,800 km)
Rotational Period ……. 5.87 days
Orbital Period ……. 5.87 days
Orbital Eccentricity ……. 0
Orbital Inclination ……. 157.4 degrees
Mean Surface Temperature ……. -391° F (-235° C)
Main Atmospheric Component ……. Nitrogen
Apparent Magnitude ……. 13.47
Triton is the 6th Proto-Earth in this Solar System