Tombaugh Regio (), sometimes nicknamed "Pluto's heart" after its shape, is the largest bright surface feature of the

dwarf planet A dwarf planet is a small planetary-mass object that is in direct orbit around the Sun, massive enough to be hydrostatic equilibrium, gravitationally rounded, but insufficient to achieve clearing the neighbourhood, orbital dominance like the ...

Pluto Pluto (minor-planet designation: 134340 Pluto) is a dwarf planet in the Kuiper belt, a ring of Trans-Neptunian object, bodies beyond the orbit of Neptune. It is the ninth-largest and tenth-most-massive known object to directly orbit the Su ...

. 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 -wide plain of

nitrogen Nitrogen is a chemical element; it has Symbol (chemistry), symbol N and atomic number 7. Nitrogen is a Nonmetal (chemistry), nonmetal and the lightest member of pnictogen, group 15 of the periodic table, often called the Pnictogen, pnictogens. ...

and other ices lying within a basin, is named

Sputnik Planitia Sputnik Planitia (formerly Sputnik Planum) is a large, partially glaciated basin on Pluto. About in size, Sputnik Planitia is partially submerged in large, bright glaciers of solid nitrogen, nitrogen ice. Named after Earth's first artificial s ...

. 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 Clyde William Tombaugh (; February 4, 1906 – January 17, 1997) was an American astronomer best known for discovering Pluto, the first object to be identified in what would later be recognized as the Kuiper belt, in 1930. Raised on farms in ...

, the discoverer of Pluto.

Description

Tombaugh Regio is a large, light-colored region about across. The two lobes of the feature are geologically distinct. The western lobe,

, is smoother than the eastern, and they are of slightly different colors. Early speculation was that the western lobe may be a large impact crater filled with nitrogen snow. Bright spots within the region were initially speculated to be mountain peaks. Photos, released on 15 July 2015, revealed mountains made of water ice in the feature; they also showed no craters in this same region. Subsequent data indicated that the center of Sputnik Planitia is rich in

carbon monoxide Carbon monoxide (chemical formula CO) is a poisonous, flammable gas that is colorless, odorless, tasteless, and slightly less dense than air. Carbon monoxide consists of one carbon atom and one oxygen atom connected by a triple bond. It is the si ...

, and

methane Methane ( , ) is a chemical compound with the chemical formula (one carbon atom bonded to four hydrogen atoms). It is a group-14 hydride, the simplest alkane, and the main constituent of natural gas. The abundance of methane on Earth makes ...

ices, and that features near the edges of the region show evidence of ice flow such as glaciers, and light material overlying the darker material at the eastern edge of Belton Regio. The surface of Sputnik Planitia is divided into polygonal convection cells and is less than 10 million years old, indicating that Pluto is geologically active. The feature had been identified as a bright spot for six decades prior to the ''New Horizons'' flyby, although it was impossible to image it with enough resolution to determine its shape. Over these six decades the spot had been observed to be dimming. In 2020, it was found that Tombaugh Regio controlled the wind circulation of Pluto, and could sculpt the landscape on its surface.

Naming and shape

On 15 July 2015, the region was provisionally named "Tombaugh Regio" by the ''New Horizons'' team in honor of astronomer

, the discoverer of Pluto, regio being Latin for "region". On 7 September 2017, the name was officially approved by the

International Astronomical Union The International Astronomical Union (IAU; , UAI) is an international non-governmental organization (INGO) with the objective of advancing astronomy in all aspects, including promoting astronomical research, outreach, education, and developmen ...

(IAU), together with names for 13 other surface features on Pluto.

NASA The National Aeronautics and Space Administration (NASA ) is an independent agencies of the United States government, independent agency of the federal government of the United States, US federal government responsible for the United States ...

initially referred to the region as a "heart" in reference to its overall shape. Some people find that it also resembles the Disney character

, an animated non-anthropomorphic dog which shares the name of the dwarf planet, in profile facing eastward.

The Walt Disney Company The Walt Disney Company, commonly referred to as simply Disney, is an American multinational mass media and entertainment conglomerate headquartered at the Walt Disney Studios complex in Burbank, California. Disney was founded on October 16 ...

acknowledged this perceived likeness in a short animation.

Gallery

References

* {{Pluto Regions of Pluto

Description

Naming and shape

Gallery

See also

References