Thomagata Patera
Encyclopedia
Thomagata Patera is a volcano
on Jupiter's
moon
Io
. It is located on Io's anti-Jupiter hemisphere at 25.67°N 165.94°W, to the east of the nearby active volcanoes Volund and Zamama. Thomagata is a kidney-shaped Ionian patera, a type of volcanic crater similar to a caldera
, 56 kilometres (34.8 mi) long, 26 km (16.2 mi) wide, and 1.2–1.6 km (0.745647283979768–0.994196378639691 mi) deep. The volcano is currently inactive as a thermal hotspot has never been observed at Thomagata and the bright floor of the patera suggests that it is cold enough for sulfur dioxide
and sulfur
to condense. Thomagata is located near the center of a low, 100 km (62.1 mi) wide mesa. The edge of the mesa rises 200 metres (656.2 ft) above the surrounding plains, however the slope up to the edge of Thomagata Patera is unknown. If the floor of the patera is at the same level as the surrounding plains, the western slope of the mesa would have a grade of 2°. The morphology of this mesa and the pattern of faded lava flows along its slopes radiating away from Thomagata (at least on its eastern side) suggest that Thomagata Patera and the mesa that surrounds it may be a shield volcano
, also called a tholus on Io. The irregular margin of the mesa and the lack of debris at the base of its basal scarp
suggest that it was modified by sulfur dioxide sapping
.
Following detailed observations of the volcano by the Galileo spacecraft in October 2001, Thomagata Patera was named
in 2006 by the International Astronomical Union
(IAU) after the Chibcha
storm god, Thomagata. According to the IAU, the mythical Thomagata was "a terrifying fire spirit who flew through the air changing men into animals."
Volcano
2. Bedrock3. Conduit 4. Base5. Sill6. Dike7. Layers of ash emitted by the volcano8. Flank| 9. Layers of lava emitted by the volcano10. Throat11. Parasitic cone12. Lava flow13. Vent14. Crater15...
on Jupiter's
Jupiter
Jupiter is the fifth planet from the Sun and the largest planet within the Solar System. It is a gas giant with mass one-thousandth that of the Sun but is two and a half times the mass of all the other planets in our Solar System combined. Jupiter is classified as a gas giant along with Saturn,...
moon
Natural satellite
A natural satellite or moon is a celestial body that orbits a planet or smaller body, which is called its primary. The two terms are used synonymously for non-artificial satellites of planets, of dwarf planets, and of minor planets....
Io
Io (moon)
Io ) is the innermost of the four Galilean moons of the planet Jupiter and, with a diameter of , the fourth-largest moon in the Solar System. It was named after the mythological character of Io, a priestess of Hera who became one of the lovers of Zeus....
. It is located on Io's anti-Jupiter hemisphere at 25.67°N 165.94°W, to the east of the nearby active volcanoes Volund and Zamama. Thomagata is a kidney-shaped Ionian patera, a type of volcanic crater similar to a caldera
Caldera
A caldera is a cauldron-like volcanic feature usually formed by the collapse of land following a volcanic eruption, such as the one at Yellowstone National Park in the US. They are sometimes confused with volcanic craters...
, 56 kilometres (34.8 mi) long, 26 km (16.2 mi) wide, and 1.2–1.6 km (0.745647283979768–0.994196378639691 mi) deep. The volcano is currently inactive as a thermal hotspot has never been observed at Thomagata and the bright floor of the patera suggests that it is cold enough for sulfur dioxide
Sulfur dioxide
Sulfur dioxide is the chemical compound with the formula . It is released by volcanoes and in various industrial processes. Since coal and petroleum often contain sulfur compounds, their combustion generates sulfur dioxide unless the sulfur compounds are removed before burning the fuel...
and sulfur
Sulfur
Sulfur or sulphur is the chemical element with atomic number 16. In the periodic table it is represented by the symbol S. It is an abundant, multivalent non-metal. Under normal conditions, sulfur atoms form cyclic octatomic molecules with chemical formula S8. Elemental sulfur is a bright yellow...
to condense. Thomagata is located near the center of a low, 100 km (62.1 mi) wide mesa. The edge of the mesa rises 200 metres (656.2 ft) above the surrounding plains, however the slope up to the edge of Thomagata Patera is unknown. If the floor of the patera is at the same level as the surrounding plains, the western slope of the mesa would have a grade of 2°. The morphology of this mesa and the pattern of faded lava flows along its slopes radiating away from Thomagata (at least on its eastern side) suggest that Thomagata Patera and the mesa that surrounds it may be a shield volcano
Shield volcano
A shield volcano is a type of volcano usually built almost entirely of fluid lava flows. They are named for their large size and low profile, resembling a warrior's shield. This is caused by the highly fluid lava they erupt, which travels farther than lava erupted from more explosive volcanoes...
, also called a tholus on Io. The irregular margin of the mesa and the lack of debris at the base of its basal scarp
Escarpment
An escarpment is a steep slope or long cliff that occurs from erosion or faulting and separates two relatively level areas of differing elevations.-Description and variants:...
suggest that it was modified by sulfur dioxide sapping
Groundwater sapping
Groundwater sapping is the geomorphic process in which groundwater exits a bank or hillslope laterally as seeps and springs and erodes soil from the slope. This often causes the slope to be undermined and undergo mass wasting, hence the word sapping....
.
Following detailed observations of the volcano by the Galileo spacecraft in October 2001, Thomagata Patera was named
Planetary nomenclature
Planetary nomenclature, like terrestrial nomenclature, is a system of uniquely identifying features on the surface of a planet or natural satellite so that the features can be easily located, described, and discussed. The task of assigning official names to features is taken up by the International...
in 2006 by the International Astronomical Union
International Astronomical Union
The International Astronomical Union IAU is a collection of professional astronomers, at the Ph.D. level and beyond, active in professional research and education in astronomy...
(IAU) after the Chibcha
Muisca
Muisca was the Chibcha-speaking tribe that formed the Muisca Confederation of the central highlands of present-day Colombia. They were encountered by the Spanish Empire in 1537, at the time of the conquest...
storm god, Thomagata. According to the IAU, the mythical Thomagata was "a terrifying fire spirit who flew through the air changing men into animals."