Oberon

Click image for description
Discovery
Discovered by	William Herschel
Discovered in	January 11, 1787
Orbital characteristics
Mean radius	583,519 km
Eccentricity	0.0014
Orbital period	13.463234 d
Inclination	0.058° (to Uranus' equator)
Is a satellite of	Uranus
Physical characteristics
Mean diameter	1522.8 km
Surface area	7,285,000 km2
Volume	1,849,000,000 km3
Mass	3.014×1021 kg
Mean density	1.63 g/cm3
Surface gravity	0.346 m/s2
Escape velocity	0.73 km/s
Rotation period	?
Axial tilt	?°
Albedo	0.23
Surface temp.	min mean max  ? K ~61 K  ? K
Atmospheric pressure	0 kPa

Oberon (oe'-bur-on) is the outermost of the major moons of the planet Uranus. It was discovered on January 11, 1787 by William Herschel. Original Caption Released with Image: This Voyager 2 picture of Oberon is the best the spacecraft acquired of Uranus outermost moon. ... Sir Wilhelm Friedrich Herschel, FRS (Hanover, November 15, 1738 – August 25, 1822 Slough, then in Buckinghamshire now in Berkshire) was a German-born British astronomer and composer who became famous for discovering the planet Uranus, and made many other astronomical discoveries. ... January 11 is the 11th day of the year in the Gregorian calendar. ... 1787 was a common year starting on Monday (see link for calendar). ... In physics, an orbit is the path that an object makes, around another object, whilst under the influence of a source of centripetal force, such as gravity. ... In classical geometry, a radius of a circle or sphere is any line segment with one endpoint on the circle (i. ... A kilometre (American spelling: kilometer), symbol: km is a unit of length in the metric system equal to 1000 metres (from the Greek words χίλια (khilia) = thousand and μέτρο (metro) = count/measure). ... In astrodynamics, under standard assumptions any orbit must be of conic section shape. ... The orbital period is the time it takes a planet (or another object) to make one full orbit. ... Inclination is one of the six orbital parameters describing the shape and orientation of a celestial orbit and is the angular distance of the orbital plane from the plane of the reference (usually planets equator or the ecliptic), stated in degrees. ... Moons of solar system scaled to Earths Moon The common noun moon (not capitalized) is used to mean any natural satellite of the other planets. ... Atmospheric characteristics Atmospheric pressure 120 kPa Hydrogen 83% Helium 15% Methane 1. ... For the geometric term, see diameter. ... -1... Square kilometre (US spelling: Square kilometer), symbol km², is an SI unit of surface area. ... Volume, also called capacity, is a quantification of how much space an object occupies. ... A cubic kilometre (symbol km³) is an SI derived unit of volume. ... Mass is a property of physical objects that, roughly speaking, measures the amount of matter they contain. ... The international prototype, made of platinum-iridium, which is kept at the BIPM under conditions specified by the 1st CGPM in 1889. ... Density (symbol: ρ - Greek: rho) is a measure of mass per unit of volume. ... It has been suggested that gravitation be merged into this article or section. ... Acceleration is the time rate of change of velocity, and at any point on a v-t graph, it is given by the gradient of the tangent to that point In physics, acceleration (symbol: a) is defined as the rate of change (or time derivative) of velocity. ... In physics, for a given gravitational field and a given position, the escape velocity is the minimum speed an object without propulsion, at that position, needs to have to move away indefinitely from the source of the field, as opposed to falling back or staying in an orbit within a... On a prograde planet like the Earth, the sidereal day is shorter than the solar day. ... Axial tilt is an astronomical term regarding the inclination angle of a planets rotational axis in relation to its orbital plane. ... The albedo is a measure of reflectivity of a surface or body. ... Temperature is the physical property of a system which underlies the common notions of hot and cold; the material with the higher temperature is said to be hotter. ... The kelvin (symbol: K) is the SI unit of temperature, and is one of the seven SI base units. ... diurnal (daily) rhythm of air pressure in northern Germany (black curve is air pressure) Atmospheric pressure is the pressure above any area in the Earths atmosphere caused by the weight of air. ... The pascal (symbol Pa) is the SI unit of pressure. ... Moons of solar system scaled to Earths Moon The common noun moon (not capitalized) is used to mean any natural satellite of the other planets. ... Atmospheric characteristics Atmospheric pressure 120 kPa Hydrogen 83% Helium 15% Methane 1. ... January 11 is the 11th day of the year in the Gregorian calendar. ... 1787 was a common year starting on Monday (see link for calendar). ... Sir Wilhelm Friedrich Herschel, FRS (Hanover, November 15, 1738 – August 25, 1822 Slough, then in Buckinghamshire now in Berkshire) was a German-born British astronomer and composer who became famous for discovering the planet Uranus, and made many other astronomical discoveries. ...

Name

The name "Oberon" and the names of all four satellites of Uranus then known were suggested by Herschel's son John Herschel in 1852 at the request of William Lassell, who had discovered Ariel and Umbriel the year before ([1]). Lassell had earlier endorsed Herschel's 1847 naming scheme for the seven then-known satellites of Saturn and had named his newly-discovered eighth satellite Hyperion in accordance with Herschel's naming scheme in 1848. John Herschel Sir John Frederick William Herschel (7 March 1792 – 11 May 1871) was an English mathematician and astronomer. ... 1852 was a leap year starting on Thursday (see link for calendar). ... William Lassell (June 18, 1799 – October 5, 1880) was a British astronomer, born in Bolton, Greater Manchester, England. ... Atmospheric pressure 0 kPa Ariel (air-ee-ul, pronounced ) is a moon of Uranus discovered on 1851-10-24 by William Lassell. ... Atmospheric pressure 0 kPa Umbriel (um-bree-ul) is a moon of Uranus discovered on 1851-10-24 by William Lassell. ... 1847 was a common year starting on Friday (see link for calendar). ... Hyperion (hye-peer-ee-un, Greek ‘Υπερίων) is a moon of Saturn discovered by William Cranch Bond, George Phillips Bond and William Lassell in 1848. ... 1848 is a leap year starting on Saturday of the Gregorian calendar. ...

All of the moons of Uranus are named for characters from Shakespeare or Alexander Pope. Oberon was named after Oberon, the king of the Faeries in A Midsummer Night's Dream. Wikipedia does not yet have an article with this exact name. ... Alexander Pope, an English poet best known for his Essay on Criticism and Rape of the Lock Pope, circa 1727. ... Oberon, also Auberon, King of the Fairies, is most famous as a character in William Shakespeares play, A Midsummer Nights Dream, written in the mid-1590s. ... A Midsummer Nights Dream is a romantic comedy by William Shakespeare written sometime in the mid-1590s. ...

It is also designated Uranus IV.

Physical features

So far the only close-up images of Oberon are from the Voyager 2 probe, which photographed the moon during its Uranus flyby in January, 1986. At the time of the flyby the southern hemisphere of the moon was pointed towards the Sun so only it was studied. The Voyager 2 spacecraft was launched in 1977. ... Look up January in Wiktionary, the free dictionary January is the first month of the year in the Gregorian Calendar and one of seven Gregorian months with the length of 31 days. ... 1986 (MCMLXXXVI) is a common year starting on Wednesday of the Gregorian calendar. ... The Sun is the star at the center of our Solar system. ...

Although its interior make-up is uncertain, one model suggests that Oberon is composed of roughly 50% water ice, 30% silicate rock, and 20% methane-related carbon/nitrogen compounds. It has an old, heavily cratered, and icy surface which shows little evidence of internal activity other than some unknown dark material that apparently covers the floors of many craters. In chemistry, a silicate is a compound consisting of silicon and oxygen (SixOy), one or more metals, and possibly hydrogen. ... R-phrases S-phrases , , , Flash point −188 °C Autoignition temperature 537 °C Explosive limits 5–15% Supplementary data page Structure and properties n, εr, etc. ... General Name, Symbol, Number carbon, C, 6 Chemical series nonmetals Group, Period, Block 14, 2, p Appearance black (graphite) colorless (diamond) Atomic mass 12. ... This article does not cite its references or sources. ...

Scientists recognise only two types of geological feature on Oberon: craters and chasmata. This article is about impact craters, also known as meteor craters. ... Chasma (pl. ...

See also

• List of geological features on Oberon