Javascript must be enabled to use all features of this site and to avoid misfunctions
Moon vs. Neptune - Comparison of sizes
HOME
Select category:
Planets
Select category
NEW

Advertising

Cancel

Search in
Close

Moon vs Neptune - Comparison

Moon
Neptune
Change

Moon

Moon

Diameter (km)3476
Distance to sun (km)363105,021
Equator (km)10921
Temperature-160

The Moon is an astronomical body orbiting Earth as its only natural satellite. It is the fifth-largest satellite in the Solar System, and by far the largest among planetary satellites relative to the size of the planet that it orbits (its primary). The Moon is, after Jupiter's satellite Io, the second-densest satellite in the Solar System among those whose densities are known. The Moon is thought to have formed about 4.51 billion years ago, not long after Earth. The most widely accepted explanation is that the Moon formed from the debris left over after a giant impact between Earth and a hypothetical Mars-sized body called Theia. New research of Moon rocks, although not rejecting the Theia hypothesis, suggests that the Moon may be older than previously thought.The Moon is in synchronous rotation with Earth, and thus always shows the same side to Earth, the near side. Because of libration, slightly more than half (about 59%) of the total lunar surface can be viewed from Earth. The near side is marked by dark volcanic maria that fill the spaces between the bright ancient crustal highlands and the prominent impact craters. After the Sun, the Moon is the second-brightest celestial object regularly visible in Earth's sky. Its surface is actually dark, although compared to the night sky it appears very bright, with a reflectance just slightly higher than that of worn asphalt. Its gravitational influence produces the ocean tides, body tides, and the slight lengthening of the day. The Moon's average orbital distance is 384,402 km (238,856 mi), or 1.



28 light-seconds. This is about thirty times the diameter of Earth. The Moon's apparent size in the sky is almost the same as that of the Sun, since the star is about 400 times the lunar distance and diameter. Therefore, the Moon covers the Sun nearly precisely during a total solar eclipse. This matching of apparent visual size will not continue in the far future because the Moon's distance from Earth is gradually increasing. The Moon was first reached by a human-made object in September 1959, when the Soviet Union's Luna 2, an unmanned spacecraft, was intentionally crashed onto the lunar surface. This accomplishment was followed by the first successful soft landing on the Moon by Luna 9 in 1966. The United States' NASA Apollo program achieved the only manned lunar missions to date, beginning with the first manned orbital mission by Apollo 8 in 1968, and six manned landings between 1969 and 1972, with the first being Apollo 11 in July 1969. These missions returned lunar rocks which have been used to develop a geological understanding of the Moon's origin, internal structure, and the Moon's later history. Since the 1972 Apollo 17 mission, the Moon has been visited only by unmanned spacecraft. Both the Moon's natural prominence in the earthly sky and its regular cycle of phases as seen from Earth have provided cultural references and influences for human societies and cultures since time immemorial. Such cultural influences can be found in language, lunar calendar systems, art, and mythology.

Source: Wikipedia
Change
Neptune

Neptune

Diameter (km)49.528
Distance to sun (km)4501000000
Equator (km)155600
Temperature-201

<p>Neptune is the eighth and farthest known planet from the Sun in the Solar System. </p>In the Solar System, it is the fourth-largest planet by the third-most-massive planet diameter, and the densest giant planet. Neptune is 17 times the mass of Earth, slightly more massive than its near-twin Uranus. Neptune is physically smaller than Uranus and thicker because its mass causes gravitational compression of its atmosphere. Neptune orbits the Sun once every 164.8 years at a mean distance of 30.1 AU (4.5 billion km; 2.8 billion mi). It is named after the Roman god of the sea and has the astronomical symbol ♆, a stylised version of the god Neptune's trident. Neptune is not visible to the unaided eye and is the only planet in the Solar System found by forecast as opposed to by empirical observation. Changes in the orbit of Uranus directed Alexis Bouvard to deduce that its orbit was subject to gravitational perturbation. The position of Neptune was calculated from Bouvard's observations by John Couch Adams and Urbain Le Verrier following his death. Neptune was observed with a telescope on 23 by Johann Galle within a degree of the position predicted by Le Verrier. Though none of the remaining 13 known moons of the planet were located before the 20th century its largest moon, Triton, was discovered soon thereafter. The distance from Earth of the planet gives it a very small apparent size, which makes it challenging to research with Earth-based telescopes. Voyager 2 visited neptune, when it flew by the planet on 25 August 1989; Voyager 2 remains the only spacecraft to visit Neptune.



The advent of the Hubble Space Telescope and large ground-based telescopes with adaptive optics has allowed for further observations from afar. Like Jupiter and Saturn, Neptune's atmosphere is composed primarily of hydrogen and helium, together with traces of hydrocarbons and possibly nitrogen, even though it includes a higher proportion of"ices" such as water, ammonia and methane. However, similar to Uranus, its interior is primarily composed of ices and rock; Uranus and Neptune are normally considered"ice giants" to emphasise this distinction. Traces of methane in the outermost areas in part account for the world's blue appearance.In contrast to the hazy, relatively featureless atmosphere of Uranus, Neptune's atmosphere has visible and active weather patterns. For example, in the time of the Voyager 2 flyby in 1989, the world's southern hemisphere had a Great Dark Spot comparable to the Great Red Spot. These weather patterns are driven by the strongest sustained winds of almost any planet in the Solar System, with recorded wind speeds as high as 2,100 km/h (580 m/s; 1,300 mph). Due to its great distance from the Sun, Neptune's outer atmosphere is one of the coldest places in the Solar System, with temperatures in its cloud tops approaching 55 K (−218 °C; −361 °F). Temperatures in the world's centre are approximately 5,400 K (5,100 °C; 9,300 °F). Neptune has a faint and fragmented ring system (labelled"arcs"), which was discovered in 1984, then afterwards confirmed by Voyager 2.

Source: Wikipedia

More intresting stuff