Triton is the largest moon orbiting the planet Neptune. Astronomers believe that the moon was originally a body floating in the Kuiper Belt. The Kuiper Belt is a region of dust balls, asteroids and dwarf planets like Pluto. Neptune captured Triton with its gravitational pull. Despite getting more sunlight, it is colder than Oberon, reaching minus degrees Fahrenheit at times. Triton is one of four bodies in the solar system that is currently volcanically active.
Its surface is smoothed by lava and has fewer craters than other moons. Europa may not be the largest moon in the solar system; however, it has drawn the most attention from scientists and astronomers. Because it likely has an ocean of salt water underneath its frozen surface, it is one of the most likely places to see life as we know it exist on another celestial body. NASA sent the Galileo probe to study the moons of Saturn and it returned a significant amount of information that excited observers.
It yielded enough clues to the potential for a habitable environment that NASA is sending another probe. Computer models show Ganymede might have ice and oceans stacked up in several layers like a club sandwich. Scientists first suspected Ganymede had an underground ocean in the s. The Galileo spacecraft discovered Ganymede's magnetic field in , providing evidence to support the theory. Spacecraft images of Ganymede show its surface is a mix of two types of terrain.
Forty percent of the surface is covered by highly cratered dark regions , and the remaining sixty percent is covered by a light grooved terrain , which forms intricate patterns across the moon. Some of the groove ridges are as high as 2, feet meters , and the grooves run for thousands of miles across Ganymede's surface.
The large craters on Ganymede are mostly flat, probably due to settling in the soft icy surface. Both bright and dark rays of ejecta can be seen around Ganymede's craters. In , scientists discovered irregular lumps beneath the icy surface of Ganymede.
The irregular masses may be rock formations, supported by Ganymede's icy shell for billions of years. This tells scientists that the ice is probably strong enough, at least near the surface, to support such rock masses from sinking to the bottom of the ice.
However, this anomaly could also be caused by piles of rock at the bottom of the ice. Astronomers using the Hubble Space Telescope have found evidence of a thin oxygen atmosphere on Ganymede. Ganymede is much colder than Earth, with daytime surface temperatures ranging from to degrees Fahrenheit 90 to Kelvin. The Galileo spacecraft, the first to orbit Jupiter, made the major discovery that Ganymede has its own magnetosphere — a region of charged particles that surrounds many planets but had never before been found around a moon.
Galileo even captured sounds of whistling and static caused by Ganymede's magnetosphere. The next full Moon is the Beaver Moon, and there will be a near-total lunar eclipse. It does have its own internal heat source: primarily from the decay of radioactive elements. The Moon's composition is very similar to the composition of Earth rocks, making it unique among all the large non-planetary objects in the Solar System.
Europa, one of the solar system's largest moons, orbits Jupiter. Beneath its frozen, icy surface, a Europa : The smallest and most hospitable of Jupiter's four large moons, Europa is covered in water-ice with a subsurface, liquid ocean. Similar to Ganymede, Europa has a very thin atmosphere made mostly of oxygen, due to the sublimation of the volatile ices on its surface.
Unlike the other moons on this list so far, however, Europa's icy surface and large volume make it the smoothest object in the Solar System, despite its striated appearance. The heat from tidal flexing, induced from Jupiter's gravitational pull, is thought to cause the subsurface ocean to remain liquid, driving the ice to move in a fashion similar to plate tectonics.
With surface chemicals being actively transported to the subsurface ocean below, plus the hydrothermal heating from beneath, Europa's oceans may potentially harbor extraterrestrial life. Cryovolcanic plumes, similar to Saturn's Enceladus, were first detected in Global color mosaic of Triton, taken in by Voyager 2 during its flyby of the Neptune system. The reddish color by the pole is thought to be a result of ultraviolet light reacting with methane, similar to what's been seen more recently on Pluto, pointing towards a similar origin.
Triton : Neptune's largest moon was once the Solar System's largest Kuiper belt object , but was gravitationally captured a long time ago. Orbiting close in at a mean distance of only , km, both rings and moons are nowhere to be found around Neptune until you reach a distance more than 15 times as great. Triton, during its capture, must have cleared out a huge fraction of the Neptunian system!
Orbiting in a retrograde fashion counterclockwise, as opposed to clockwise , Triton is the only large moon to exhibit this characteristic, further evidence of its captured nature. It's an active world that resurfaces itself over time, with erupting geysers, a thin, Pluto-like atmosphere, and covered in a mix of nitrogen, water, and carbon dioxide ices.
Its smoke-emitting cryovolcanoes point to a subsurface ocean and ongoing activity. Triton makes up Pluto and its moon Charon; image composite stitched together from many New Horizons images. Pluto is Pluto : Finally, we get to everyone's favorite former planet, and the first non-moon on our list. Smaller and less massive by far than Triton, and less than half the diameter of Mercury, the Plutonian system is the first one in the Kuiper belt to be imaged from up close.
Its large natural satellite, Charon, was likely formed from a giant impact, along with its four other moons: Styx, Nix, Kerberos and Hydra. Charon, in particular, is so large that it makes the Plutonian system a binary one, where the center-of-mass of the system lies outside of Pluto itself.
Its geological history also points to an active world, as giant ice mountains, snows, valleys, and sublimating plains show a frozen world in motion. Along with many worlds on this list, Pluto likely has a liquid ocean beneath the surface, raising more questions about biochemistry and organics than it answers. Eris can barely be imaged even with the most powerful of telescopes, as its extreme distance from All that we know about it have had to come from very clever measurement techniques, along with a little bit of serendipity.
The moon is a solid natural object that orbits around a planet. No definite scientific explanation has satisfactorily answered the question of how moons came into existence, although there are several theories. Each planet has one or more moons except Mercury and Venus and the dwarf planet Ceres.
Jupiter has 79 moons the highest number in the solar system. Technological advancements have made it possible for man to discover and even go on expeditions to the moon.
Jupiter's Ganymede is the largest moon in our solar system. Ganymede is the largest of Jupiter's 79 moons as well as by far the largest moon in the solar system. Ganymede orbits around Jupiter with a diameter of 5, kilometers. It is bigger in size than the smallest planet Mercury and would have easily been classified as a planet if it was orbiting the sun.
It has its own magnetic field. Its discovery was made by Galileo Galilei the Italian astronomer on January 7,
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