Neptune and Triton
Neptune is the eighth and farthest known planet orbiting the Sun. This ice giant orbits once every 164.8 years and displays extreme conditions: the strongest sustained winds of any planet at 2,100 km/h and temperatures approaching 55 K at its cloud tops. Neptune was discovered in 1846 and is unique for being mathematically predicted before observation. Triton, Neptune's largest moon at 2,706.8 kilometers in diameter, is equally remarkable. It orbits in a retrograde direction—the only large moon to do so—and is thought to have been captured from the Kuiper belt. Triton is one of the most geologically active worlds in the Solar System.
Sources
- en.wikipedia.org: “Neptune is the eighth and farthest known planet orbiting the Sun.”
- en.wikipedia.org: “Neptune orbits the Sun once every 164.8 years at an orbital distance of 30.1 astronomical units (4.5 billion kilometres; 2.8 billion miles).”
- en.wikipedia.org: “These weather patterns are driven by the strongest sustained winds of any planet in the Solar System, as high as 2,100 km/h (580 m/s; 1,300 mph). Because of its great distance from the Sun, Neptune's outer atmosphere is one of the coldest places in the Solar System, with temperatures at its cloud tops approaching 55 K (−218 °C; −361 °F).”
- en.wikipedia.org: “Neptune is not visible to the unaided eye and is the only planet in the Solar System that was not initially observed by direct empirical observation.”
- en.wikipedia.org: “At 2,706.8 kilometers (1,681.9 mi) in diameter, Triton is the seventh-largest moon in the Solar System, the second-largest planetary moon in relation to its primary (after Earth's Moon), and larger than all of the known dwarf planets.”
- en.wikipedia.org: “Triton orbits Neptune in a retrograde orbit—revolving in the opposite direction to the parent planet's rotation—the only large moon in the Solar System to do so. Triton is thought to have once been a dwarf planet from the Kuiper belt, captured into Neptune's orbit by the latter's gravity.”
- en.wikipedia.org: “Triton is one of the most geologically active worlds in the Solar System, with an estimated average surface age of less than 100 million years old.”