Puck is an

inner moon In astronomy, an inner moon or inner natural satellite is a natural satellite following a prograde, low-inclination orbit inwards of the large satellites of the parent planet. They are generally thought to have been formed ''in situ'' at the sam ...

Uranus Uranus is the seventh planet from the Sun. Its name is a reference to the Greek god of the sky, Uranus ( Caelus), who, according to Greek mythology, was the great-grandfather of Ares (Mars), grandfather of Zeus (Jupiter) and father of ...

. It was discovered in December 1985 by the ''

Voyager 2 ''Voyager 2'' is a space probe launched by NASA on August 20, 1977, to study the outer planets and interstellar space beyond the Sun's heliosphere. As a part of the Voyager program, it was launched 16 days before its twin, '' Voyager 1'', ...

'' spacecraft. The name ''Puck'' follows the convention of naming Uranus's moons after characters from

Shakespeare William Shakespeare ( 26 April 1564 – 23 April 1616) was an English playwright, poet and actor. He is widely regarded as the greatest writer in the English language and the world's pre-eminent dramatist. He is often called England's nation ...

. The orbit of Puck lies between the rings of Uranus and the first of Uranus's large moons, Miranda. Puck is approximately spherical in shape and has diameter of about 162 km. It has a dark, heavily cratered surface, which shows spectral signs of water ice.

Discovery and naming

Puck—the largest inner moon of Uranus—was discovered from the images taken by ''

'' on 30 December 1985. It was given the temporary designation S/1985 U 1. The moon was later named after the character Puck who appears in Shakespeare's ''

A Midsummer Night's Dream ''A Midsummer Night's Dream'' is a comedy written by William Shakespeare 1595 or 1596. The play is set in Athens, and consists of several subplots that revolve around the marriage of Theseus and Hippolyta. One subplot involves a conflict a ...

'', a little sprite who travels around the globe at night with the

fairies A fairy (also fay, fae, fey, fair folk, or faerie) is a type of mythical being or legendary creature found in the folklore of multiple European cultures (including Celtic, Slavic, Germanic, English, and French folklore), a form of spirit, ...

. In

Celtic mythology Celtic mythology is the body of myths belonging to the Celtic peoples.Cunliffe, Barry, (1997) ''The Ancient Celts''. Oxford, Oxford University Press , pp. 183 (religion), 202, 204–8. Like other Iron Age Europeans, Celtic peoples followed ...

and English folklore, a '' Puck'' is a mischievous sprite, imagined as an evil demon by Christians. It is also designated Uranus XV.

Physical characteristics

Puck is the largest small

of Uranus, which orbits inside the orbit of Miranda. It is intermediate in size between

Portia Portia may refer to: Biology * ''Portia'' (spider), a genus of jumping spiders *'' Anaea troglodyta'' or Portia, a brush-footed butterfly *Portia tree, a plant native to Polynesia Medication A form of birth control made of ethinylestradiol/lev ...

(the second-largest inner moon) and Miranda (the smallest of the five large classical moons). Puck's orbit is located between the rings of Uranus and Miranda. Little is known about Puck aside from its orbit, radius of about 81 km, and geometric

albedo Albedo (; ) is the measure of the diffuse reflection of solar radiation out of the total solar radiation and measured on a scale from 0, corresponding to a black body that absorbs all incident radiation, to 1, corresponding to a body that refle ...

visible light Light or visible light is electromagnetic radiation that can be perceived by the human eye. Visible light is usually defined as having wavelengths in the range of 400–700 nanometres (nm), corresponding to frequencies of 750–420 t ...

of approximately 0.11. Of the moons discovered by the ''Voyager 2'' imaging team, only Puck was discovered early enough that the probe could be programmed to image it in some detail. Images showed that Puck has a shape of a slightly

prolate A spheroid, also known as an ellipsoid of revolution or rotational ellipsoid, is a quadric surface obtained by rotating an ellipse about one of its principal axes; in other words, an ellipsoid with two equal semi-diameters. A spheroid has circ ...

spheroid A spheroid, also known as an ellipsoid of revolution or rotational ellipsoid, is a quadric surface obtained by rotating an ellipse about one of its principal axes; in other words, an ellipsoid with two equal semi-diameters. A spheroid has ...

(ratio between axes is 0.97 ± 0.04). Its surface is heavily cratered and is grey in color. There are three named craters on the surface of Puck, the largest being about 45 km in diameter. Observations with the

Hubble Space Telescope The Hubble Space Telescope (often referred to as HST or Hubble) is a space telescope that was launched into low Earth orbit in 1990 and remains in operation. It was not the first space telescope, but it is one of the largest and most vers ...

and large terrestrial telescopes found water-ice absorption features in the spectrum of Puck. Nothing is known about the internal structure of Puck. It is probably made of a mixture of water ice with the dark material similar to that found in the rings. This dark material is probably made of rocks or

radiation In physics, radiation is the emission or transmission of energy in the form of waves or particles through space or through a material medium. This includes: * ''electromagnetic radiation'', such as radio waves, microwaves, infrared, visi ...

-processed

organic Organic may refer to: * Organic, of or relating to an organism, a living entity * Organic, of or relating to an anatomical organ Chemistry * Organic matter, matter that has come from a once-living organism, is capable of decay or is the product ...

s. The absence of craters with bright rays implies that Puck is not differentiated, meaning that ice and non-ice components have not separated from each other into a

core Core or cores may refer to: Science and technology * Core (anatomy), everything except the appendages * Core (manufacturing), used in casting and molding * Core (optical fiber), the signal-carrying portion of an optical fiber * Core, the centra ...

and

mantle A mantle is a piece of clothing, a type of cloak. Several other meanings are derived from that. Mantle may refer to: *Mantle (clothing), a cloak-like garment worn mainly by women as fashionable outerwear **Mantle (vesture), an Eastern Orthodox ve ...

Named features

Puckian craters are named after mischievous spirits in European mythology.

References

Explanatory notes Citations Sources * * * * * * * *

External links

Page that includes a reprocessed version of the ''Voyager 2'' Puck image
{{DEFAULTSORT:Puck (Moon) Moons of Uranus 19851230 Things named after Shakespearean works Moons with a prograde orbit A Midsummer Night's Dream

Discovery and naming

Physical characteristics

Named features

See also

References

External links