Tholus
In planetary geology, a tholus (pl. tholi) is a small domical mountain or hill.[1] The word is from the Greek θόλος,[2] which means a circular building with a conical or vaulted roof.[3] The Romans transliterated the word into the Latin tholus, which means cupola or dome.[4] In the early 1970s, the International Astronomical Union (IAU) adopted tholus as one of a number of official descriptor terms for topographic features on Mars and other planets and satellites.[5] One justification for using neutral Latin or Greek descriptors was that it allowed features to be named and described before their geology or geomorphology could be determined.[6] For example, many tholi appear to be volcanic in origin, but the term does not imply a specific geologic origin.[7] Currently, the IAU recognizes 55 descriptor terms. (See Planetary nomenclature.) Tholi are present on Venus, Mars, and on Jupiter's moon Io.
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Map of the Tharsis quadrangle showing major features, several of which are tholi. Tharsis contains many volcanoes, including Olympus Mons, the tallest known volcano in the solar system.
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2001 Mars Odyssey THEMIS mosaic of Ceraunius Tholus (lower volcano) and Uranius Tholus (upper volcano). Ceraunius Tholus is about as high as Earth's Mount Everest.
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Western part of Jovis Tholus, as seen by THEMIS on Mars Odyssey spacecraft. Jovis Tholus is in the Tharsis quadrangle.
Examples of tholi
References
- ↑ Gazetteer of Planetary Nomenclature. http://planetarynames.wr.usgs.gov/DescriptorTerms.
- ↑ Liddell and Scott (1975). An Intermediate Greek-English Lexicon; Oxford University Press: Oxford, UK, p. 368.
- ↑ Dictionary.com. http://dictionary.reference.com/browse/tholus.
- ↑ Simpson, D.P. (1968). Cassell's New Latin Dictionary; Funk & Wagnalls: New York, p. 604.
- ↑ Greeley, R. (1994) Planetary Landscapes, 2nd ed.; Chapman & Hall: New York, pp. 35-36.
- ↑ Russell, J.F.; Snyder, C.W.; Kieffer, H.H. (1992). Origin and Use of Martian Nomenclature in Mars, H.H. Kieffer et al., Eds.; University of Arizona Press: Tucson, AZ, p. 1310.
- ↑ Russell, J.F.; Snyder, C.W.; Kieffer, H.H. (1992). Origin and Use of Martian Nomenclature in Mars, H.H. Kieffer et al., Eds.; University of Arizona Press: Tucson, AZ, p. 1312.
