Pluto is a dwarf planet in the Kuiper belt, a ring of bodies beyond the orbit of Neptune. It is the ninth-largest and tenth-most-massive known object to directly orbit the Sun. It is the largest known trans-Neptunian object by volume, by a small margin, but is less massive than Eris. Like other Kuiper belt objects, Pluto is made primarily of ice and rock and is much smaller than the inner planets. Pluto has roughly one-sixth the mass of the Moon, and one-third its volume.
Charon, or (134340) Pluto I, is the largest of the five known natural satellites of the dwarf planet Pluto. It has a mean radius of 606 km (377 mi). Charon is the sixth-largest known trans-Neptunian object after Pluto, Eris, Haumea, Makemake, and Gonggong. It was discovered in 1978 at the United States Naval Observatory in Washington, D.C., using photographic plates taken at the United States Naval Observatory Flagstaff Station (NOFS).
A Balrog is a demon from J.R.R. Tolkien's Middle-earth legendarium.
The geology of Pluto consists of the characteristics of the surface, crust, and interior of Pluto. Because of Pluto's distance from Earth, in-depth study from Earth is difficult. Many details about Pluto remained unknown until 14 July 2015, when New Horizons flew through the Pluto system and began transmitting data back to Earth. When it did, Pluto was found to have remarkable geologic diversity, with New Horizons team member Jeff Moore saying that it "is every bit as complex as that of Mars". The final New Horizons Pluto data transmission was received on 25 October 2016. In June 2020, astronomers reported evidence that Pluto may have had a subsurface ocean, and consequently may have been habitable, when it was first formed.
A dwarf planet is a small planetary-mass object that is in direct orbit around the Sun, massive enough to be gravitationally rounded, but insufficient to achieve orbital dominance like the eight classical planets of the Solar System. The prototypical dwarf planet is Pluto, which for decades was regarded as a planet before the "dwarf" concept was adopted in 2006.
Krun or Akrun is a Mandaean lord of the underworld. According to Mandaean cosmology, he dwells in the lowest depths of creation, supporting the entirety of the physical world.
Kerberos is a small natural satellite of Pluto, about 19 km (12 mi) in its longest dimension. Kerberos is also the second-smallest moon of Pluto, after Styx. It was the fourth moon of Pluto to be discovered and its existence was announced on 20 July 2011. It was imaged, along with Pluto and its four other moons, by the New Horizons spacecraft in July 2015. The first image of Kerberos from the flyby was released to the public on 22 October 2015.
Tombaugh Regio, sometimes nicknamed "Pluto's heart" after its shape, is the largest bright surface feature of the dwarf planet Pluto. It lies just north of Pluto's equator, to the northeast of Belton Regio and to the northwest of Safronov Regio, which are both dark features. Its western lobe, a 1,000 km (620 mi)-wide plain of nitrogen and other ices lying within a basin, is named Sputnik Planitia. The eastern lobe consists of high-albedo uplands thought to be coated by nitrogen transported through the atmosphere from Sputnik Planitia, and then deposited as ice. Some of this nitrogen ice then returns to Sputnik Planitia via glacial flow. The region is named after Clyde Tombaugh, the discoverer of Pluto.
Belton Regio is a prominent surface feature of the dwarf planet Pluto. It is an elongated dark region along Pluto's equator, 2,990 km (1,860 mi) long and one of the darkest features on its surface.
Mordor Macula is the informal name for a large dark area about 475 km in diameter near the north pole of Charon, Pluto's largest moon. It is named after the black land called Mordor in J.R.R. Tolkien's The Lord of the Rings.
The geography of Pluto refers to the study and mapping of physical features across the dwarf planet Pluto. On 14 July 2015, the New Horizons spacecraft became the first spacecraft to fly by Pluto. During its brief flyby, New Horizons made detailed geographical measurements and observations of Pluto and its moons.
Vucub-Came Macula is one of the "Brass Knuckles", a series of equatorial dark regions on Pluto. It is named after Wuquub' Kameh "Seven Death", one of the Quiché death gods in the Popol Vuh.
Hun-Came Macula is one of the "Brass Knuckles", a series of equatorial dark regions on Pluto. It is named after Jun Kameh "One Death", one of the Quiché death gods in the Popol Vuh.
Meng-pʻo Macula is the easternmost of the "Brass Knuckles", a series of equatorial dark regions on Pluto. Meng-pʻo straddles the zero meridian, directly under Pluto's tidally locked moon Charon and just west of the tail of the "Whale", Belton Regio. It is named after Meng Po, the Chinese underworld deity of forgetfulness.
Vader is the unofficial name given to a dark crater on Pluto's largest moon Charon. The floor of Vader is darker than the surrounding terrain, covered in the same reddish-brown dark material that covers Mordor Macula on Charon's north pole. Though Charon's surface trends darker with increasing latitude, some craters, such as Vader, interrupt this trend. The crater was discovered by NASA's New Horizons space probe on its way by Pluto. It is named after the character Darth Vader from the Star Wars media franchise; the name has yet to be officially approved by the International Astronomical Union (IAU).
Caleuche Chasma is a Y-shaped chasma on Pluto's moon, Charon. Caleuche Chasma is 400 km (250 mi) long. The feature was discovered using stereoscopic processing of New Horizons images. At approximately 13 km (8.1 mi) deep, it is the deepest known feature on the natural satellite, and one of the deepest known canyons in the Solar System.
Safronov Regio is the westernmost of the "Brass Knuckles", a series of equatorial dark regions on Pluto.
Sharaf Regio is the smallest of the "Brass Knuckles", a series of equatorial dark regions on Pluto. It was initially informally named Ala Macula after Ala "earth", the chthonic and most important deity of the Igbo people. The International Astronomical Union (IAU) officially approved the name Sharaf Regio after Shafika Gil’mievna Sharaf, a Soviet astronomer who developed an analytical theory for Pluto's motion.
