17 Surface features of Io (moon)

This is a list of named regions on Jupiter's moon Io. These names have been approved for use by the International Astronomical Union. The features listed below represent a subset of the total known bright regions on Io's surface with many currently not having an officially approved name. These areas are large-scale regions on Io's surface that are notable for their difference in brightness or color from their surroundings. In most cases, these areas are bright terrains, consisting of sulfur dioxide frost/ice fields, suggesting that they are colder than their surroundings.

This is a list of named volcanic surface features on Jupiter's moon Io. These names have been approved for use by the International Astronomical Union. The features listed below represent a subset of the total known volcanic features on Io's surface with the majority currently not having an officially approved name.

Amaterasu Patera is a patera, a complex crater with scalloped edges, on Jupiter's moon Io. It is one of the darkest features on Io, and the measurement of its thermal spectrum helped to support an anticorrelation between albedo and temperature for Ionian hotspots. The feature has darkened further since the first orbit around Jupiter by the Galileo spacecraft. It is 100 kilometers in diameter and located at 38.1°N 306.5°W. It was named after the Japanese sun goddess Amaterasu. To the north are Kinich Ahau Patera and Dazhbog Patera, and to the west are Manua Patera and Fuchi Patera.

Asha Patera is a patera, or a complex crater with scalloped edges, on Jupiter's moon Io. It is approximately 108 kilometers in diameter and located at 8.84°S 225.69°W. It is named after asha, the Zoroastrian principle of Truth. Its name was adopted by the International Astronomical Union in 1979. Reiden Patera and Kami-Nari Patera can both be found to the west.

Babbar Patera is a patera, or a complex crater with scalloped edges, on Jupiter's moon Io. It is about 86 kilometers in diameter and is located at 39.8°S 272°W. It is named after a Sumerian sun god, and its name was approved by the International Astronomical Union in 1979. Some scarps near Babbar Patera may represent faults. Immediately south of Babbar Patera is the plateau Lyrcea Planum, and further south is Svarog Patera. To the east is the mountain Egypt Mons.

The Chaac-Camaxtli region is a volcanic region on Jupiter's moon Io, located from approximately 5 to 20°N and 130 to 160°W in its anti-Jovian hemisphere. It consists mainly of the hummocky bright plains that occupy the surface. This area is defined on the west by Chaac Patera, and on the east by Camaxtli Patera. At least 10 distinct volcanic centers are located in the region, making it a volcanically active region on Io's surface. Most of the volcanism here is expressed as paterae, which range in size from circular to elliptical. A patera is defined by the International Astronomical Union as "irregular or complex craters with scalloped edges." The largest volcanic structure here is the Chaac Patera. The paterae found in the Chaac-Camaxtli region are Chaac, Balder Patera, Grannos, Ababinili, Ruaumoko, Steropes, Camaxtli, Tien Mu, Utu, and Mentu.

Fuchi Patera is a patera, or a complex crater with scalloped edges, on Jupiter's moon Io. It is approximately 66 kilometers in diameter and is located at 28.4°N 327.6°W. It is named after the Ainu fire goddess, Kamuy Fuchi. Its name was adopted by the International Astronomical Union in 1979. Manua Patera is located north-northeast, and Amaterasu Patera is located northeast.

Kami-Nari Patera is a patera, or a complex crater with scalloped edges, on Jupiter's moon Io. It is approximately 53 kilometers in diameter and is located at 8.7°S 235.08°W. It is named after the Japanese god of rolling thunder, Kami-Nari. Its name was adopted by the International Astronomical Union in 2000. Reiden Patera can be found to the south, and Asha Patera can be found to the east.

Kinich Ahau Patera is a patera, or a complex crater with scalloped edges, on Jupiter's moon Io. It is about 45 kilometers in diameter and is located at 49.35°N 310.25°W. It is named after the Mayan sun god Kinich Ahau. Dazhbog Patera is located northeast, Amaterasu Patera is located south-southeast, and Manua Patera can be found southwest.

Manua Patera is a patera, or a complex crater with scalloped edges, on Jupiter's moon Io. It is about 110 kilometers in diameter and is located at 35.78°N 321.73°W. It is named after the Hawaiian sun god Manua. Its name was adopted by the International Astronomical Union in 1979. To the southwest is Fuchi Patera, and to the east is Amaterasu Patera.

Mithra Patera is a patera, or a complex crater with scalloped edges, on Jupiter's moon Io. It is about 34 kilometers in diameter and is located at 59.04°S 266.48°W. It is named after the Persian god of light, Mithra. Its name was adopted by the International Astronomical Union in 1985. To the north is Silpian Mons, and to the east is Pyerun Patera. Located southwest is Viracocha Patera.

Monan Patera is a patera, or a complex crater with scalloped edges, on Jupiter's moon Io. It is about 137 kilometers in diameter and is located at 19.82°N 104.81°W. It is named after Monan, a god in Brazilian mythology that destroyed the world with fire and floods. Its name was adopted by the International Astronomical Union in 1997.

Pyerun Patera is a patera, or a complex crater with scalloped edges, on Jupiter's moon Io. It is about 57 kilometers in diameter and is located at 55.65°S 251.06°W. It is named after the Slavonic god of thunder, Pyerun. The name was adopted by the International Astronomical Union in 1985. West of Pyerun Patera is Mithra Patera, and to the east is the mesa Epaphus Mensa. To the northeast is Epaphus Mensa, and to the northwest are the mountain Silpium Mons and Svarog Patera.

Svarog Patera is a patera, or a complex crater with scalloped edges, on Jupiter's moon Io. It is 124 kilometers in diameter and is located at 48.66°S 265.74°W. It is named after the Russian smith god Svarog. Its name was approved by the International Astronomical Union in 1979. North of Svarog Patera is Lyrcea Planum, north of which is Babbar Patera. To the south is Silpium Mons, and to the east is Hermes Mensa. To the southeast are Pyerun Patera and Epaphus Mensa. Svarog Patera is a Voyager spacecraft-detected hot spot.

Tawhaki Vallis is a shallow valley on Jupiter's moon Io. It is located on Io's leading hemisphere in the equatorial plains of western Media Regio at 0.5°N 72.8°W. The valley is 190 kilometers long, 0.5 to 6 km wide, and 40 to 65 meters deep. Due to the shallow depth and lack of brightness or color variations associated with it, Tawhaki Vallis was seen in only a single, high-spatial-resolution observation taken by Galileo during an Io encounter on November 26, 1999. The northern and southern ends of the valley are cut off by the northern margin of the observation and the dusk terminator, so Tawhaki could be longer than the measured length. The valley was formally named Tawhaki Vallis by the International Astronomical Union in 2006 after a nearby volcano, Tawhaki Patera, and the Māori lightning god, Tāwhaki.

Tvashtar Paterae compose an active volcanic region of Jupiter's moon Io located near its north pole. It is a series of paterae, or volcanic craters. It is named after Tvashtar, the Hindu god of blacksmiths. Tvashtar was discovered in IRTF images in November 26 1999, several hours after a Galileo flyby. Images taken with the ESO 3.6m telescope and its adaptive optics in September 1999 revealed the presence of faint hot spot. The outburst was studied by the Galileo spacecraft over several years. During this time, a 25-kilometre (16 mi) long, 1-to-2-kilometre high curtain of lava was seen to erupt from one patera, a lake of superheated silicate lava erupted in the largest patera, and finally a plume of gas burst out, rising 385 kilometres (239 mi) above Io and blanketing areas as far away as 700 kilometres (430 mi).

Viracocha Patera is a patera, or a complex crater with scalloped edges, on Jupiter's moon Io. It is about 61 kilometers in diameter and is located at 61.75°S 280.07°W. It is named after the Quechua creator god Viracocha. The name was adopted by the International Astronomical Union in 1979. Viracocha Patera is a Voyager spacecraft-detected hot spot. To Viracocha Patera's east-northeast is Mithra Patera, and to the northeast is the mountain Silpium Mons.