Geyser

This is a good article. Click here for more information.
From Wikipedia, the free encyclopedia
Geyser
Formed byParticular hydrogeological conditions that exist in a few places on Earth
A cross-section of a geyser in action

A geyser (/ˈɡzər/, UK: /ˈɡzər/)[1][2] is a spring characterized by an intermittent discharge of water ejected turbulently and accompanied by steam. As a fairly rare phenomenon, the formation of geysers is due to particular hydrogeological conditions that exist only in a few places on Earth.

Generally, geyser field sites are located near active volcanic areas, and the geyser effect is due to the proximity of magma. Surface water works its way down to an average depth of around 2,000 metres (6,600 ft) where it contacts hot rocks. The resultant boiling of the pressurized water results in the geyser effect of hot water and steam spraying out of the geyser's surface vent.

A geyser's eruptive activity may change or cease due to ongoing mineral deposition within the geyser plumbing, exchange of functions with nearby hot springs, earthquake influences, and human intervention.[3] Like many other natural phenomena, geysers are not unique to Earth. Jet-like eruptions, often referred to as cryogeysers, have been observed on several of the moons of the outer solar system. Due to the low ambient pressures, these eruptions consist of vapor without liquid; they are made more easily visible by particles of dust and ice carried aloft by the gas. Water vapor jets have been observed near the south pole of Saturn's moon Enceladus, while nitrogen eruptions have been observed on Neptune's moon Triton.

There are also signs of carbon dioxide eruptions from the southern polar ice cap of Mars. In the case of Enceladus, the plumes are believed to be driven by internal energy. In the cases of the venting on Mars and Triton, the activity may be a result of solar heating via a solid-state greenhouse effect. In all three cases, there is no evidence of the subsurface hydrological system which differentiates terrestrial geysers from other sorts of venting, such as fumaroles.

Etymology[edit]

The term 'geyser' in English dates back to the late 18th century and comes from Geysir, which is a geyser in Iceland.[4] Its name means "one who gushes".[4][5]

Geology[edit]

Form and function[edit]

Water and steam erupting from rocky, barren ground. Fir trees in the background.
Steamboat Geyser in Yellowstone National Park

Geysers are nonpermanent geological features. Geysers are generally associated with volcanic areas.[6][better source needed] As the water boils, the resulting pressure forces a superheated column of steam and water to the surface through the geyser's internal plumbing. The formation of geysers specifically requires the combination of three geologic conditions that are usually found in volcanic terrain: intense heat, water, and a waterworks system.[6][better source needed]

The heat needed for geyser formation comes from magma that needs to be close to the surface of the earth.[7] In order for the heated water to form a geyser, a plumbing system (made of fractures, fissures, porous spaces, and sometimes cavities) is required. This includes a reservoir to hold the water while it is being heated. Geysers are generally aligned along faults.[6][better source needed]

Eruptions[edit]

Strokkur geyser erupting (clockwise from top left)
  1. Steam rises from heated water
  2. Pulses of water swell upward
  3. Surface is broken
  4. Ejected water spouts upward and falls back down into the pipe

Geyser activity, like all hot spring activity, is caused by surface water gradually seeping down through the ground until it meets rock heated by magma. In non-eruptive hot springs, the geothermally heated water then rises back toward the surface by convection through porous and fractured rocks, while in geysers, the water instead is explosively forced upwards by the high steam pressure created when water boils below. Geysers also differ from non-eruptive hot springs in their subterranean structure; many consist of a small vent at the surface connected to one or more narrow tubes that lead to underground reservoirs of water and pressure tight rock.[8]

As the geyser fills, the water at the top of the column cools off, but because of the narrowness of the channel, convective cooling of the water in the reservoir is impossible. The cooler water above presses down on the hotter water beneath, not unlike the lid of a pressure cooker, allowing the water in the reservoir to become superheated, i.e. to remain liquid at temperatures well above the standard-pressure boiling point.[8]

Ultimately, the temperatures near the bottom of the geyser rise to a point where boiling begins, forcing steam bubbles to rise to the top of the column. As they burst through the geyser's vent, some water overflows or splashes out, reducing the weight of the column and thus the pressure on the water below. With this release of pressure, the superheated water flashes into steam, boiling violently throughout the column. The resulting froth of expanding steam and hot water then sprays out of the geyser vent.[6][better source needed][9]

A key requirement that enables a geyser to erupt is a material called geyserite found in rocks nearby the geyser. Geyserite, mostly silicon dioxide (SiO2), is dissolved from the rocks and is deposited on the walls of the geyser's plumbing system and on the surface. The deposits make the channels carrying the water up to the surface pressure-tight. This allows the pressure to be carried all the way to the top and not leak out into the loose gravel or soil that are normally under the geyser fields.[8]

Eventually the water remaining in the geyser cools back to below the boiling point and the eruption ends; heated groundwater begins seeping back into the reservoir, and the whole cycle begins again. The duration of eruptions and time between successive eruptions vary greatly from geyser to geyser; Strokkur in Iceland erupts for a few seconds every few minutes, while Grand Geyser in the United States erupts for up to 10 minutes every 8–12 hours.[8]

General categorization[edit]

There are two types of geysers: fountain geysers which erupt from pools of water, typically in a series of intense, even violent, bursts; and cone geysers which erupt from cones or mounds of siliceous sinter (including geyserite), usually in steady jets that last anywhere from a few seconds to several minutes. Old Faithful, perhaps the best-known geyser at Yellowstone National Park, is an example of a cone geyser. Grand Geyser, the tallest predictable geyser on earth, (although Geysir in Iceland is taller, it is not predictable), also at Yellowstone National Park, is an example of a fountain geyser.[10]

Geyser erupts up and blows sideways from a pool.
High geyser of water erupts out of the sparsely vegetated earth.
Fountain Geyser erupting from the pool (left) and Old Faithful geyser (cone geyser having mound of siliceous sinter) in Yellowstone National Park erupts approximately every 91 minutes (right).

There are many volcanic areas in the world that have hot springs, mud pots and fumaroles, but very few have erupting geysers. The main reason for their rarity is because multiple intense transient forces must occur simultaneously for a geyser to exist. For example, even when other necessary conditions exist, if the rock structure is loose, eruptions will erode the channels and rapidly destroy any nascent geysers.[11]

Geysers are fragile phenomena and if conditions change, they may go dormant or extinct. Many have been destroyed simply by people throwing debris into them while others have ceased to erupt due to dewatering by geothermal power plants. However, the Geysir in Iceland has had periods of activity and dormancy. During its long dormant periods, eruptions were sometimes artificially induced—often on special occasions—by the addition of surfactant soaps to the water.[12]

Biology[edit]

Surreal blue pool surround by orange border on a purple ground.
Hyperthermophiles produce some of the bright colors of Grand Prismatic Spring, Yellowstone National Park

The specific colours of geysers derive from the fact that despite the apparently harsh conditions, life is often found in them (and also in other hot habitats) in the form of thermophilic prokaryotes. No known eukaryote can survive over 60 °C (140 °F).[13]

In the 1960s, when the research of the biology of geysers first appeared, scientists were generally convinced that no life can survive above around 73 °C maximum (163 °F)—the upper limit for the survival of cyanobacteria, as the structure of key cellular proteins and deoxyribonucleic acid (DNA) would be destroyed. The optimal temperature for thermophilic bacteria was placed even lower, around 55 °C average (131 °F).[13]

However, the observations proved that it is actually possible for life to exist at high temperatures and that some bacteria even prefer temperatures higher than the boiling point of water. Dozens of such bacteria are known.[14] Thermophiles prefer temperatures from 50 to 70 °C (122 to 158 °F), whilst hyperthermophiles grow better at temperatures as high as 80 to 110 °C (176 to 230 °F). As they have heat-stable enzymes that retain their activity even at high temperatures, they have been used as a source of thermostable tools, that are important in medicine and biotechnology,[15] for example in manufacturing antibiotics, plastics, detergents (by the use of heat-stable enzymes lipases, pullulanases and proteases), and fermentation products (for example ethanol is produced). Among these, the first discovered and the most important for biotechnology is Thermus aquaticus.[16]

Major geyser fields and their distribution[edit]

Map showing that locations of geysers tend to cluster in specific areas of the world.
Distribution of major geysers in the world.

Geysers are quite rare, requiring a combination of water, heat, and fortuitous plumbing. The combination exists in few places on Earth.[17][18]

Yellowstone National Park, U.S.[edit]

Yellowstone is the largest geyser locale, containing thousands of hot springs, and approximately 300 to 500 geysers. It is home to half of the world's total number of geysers in its nine geyser basins. It is located mostly in Wyoming, USA, with small portions in Montana and Idaho.[19] Yellowstone includes the world's tallest active geyser (Steamboat Geyser in Norris Geyser Basin).

Valley of Geysers, Russia[edit]

Breathing Geyser Double, Valley of Geysers in Kamchatka Krai

The Valley of Geysers (Russian: Долина гейзеров) located in the Kamchatka Peninsula of Russia is the second largest concentration of geysers in the world. The area was discovered and explored by Tatyana Ustinova in 1941. Approximately 200 geysers exist in the area along with many hot-water springs and perpetual spouters. The area was formed due to a vigorous volcanic activity. The peculiar way of eruptions is an important feature of these geysers. Most of the geysers erupt at angles, and only very few have the geyser cones that exist at many other of the world's geyser fields.[18] On June 3, 2007, a massive mudflow influenced two thirds of the valley.[20] It was then reported that a thermal lake was forming above the valley.[21] Few days later, waters were observed to have receded somewhat, exposing some of the submerged features. Velikan Geyser, one of the field's largest, was not buried in the slide and has recently[quantify] been observed to be active.[22]

El Tatio, Chile[edit]

A geyser bubbling at El Tatio geyser field

The name "El Tatio" comes from the Quechua word for oven. El Tatio is located in the high valleys on the Andes surrounded by many active volcanoes in Chile, South America at around 4,200 metres (13,800 ft) above mean sea level. The valley is home to approximately 80 geysers at present. It became the largest geyser field in the Southern Hemisphere after the destruction of many of the New Zealand geysers, and is the third largest geyser field in the world. The salient feature of these geysers is that the height of their eruptions is very low, the tallest being only six metres (20 ft) high, but with steam columns that can be over 20 metres (66 ft) high. The average geyser eruption height at El Tatio is about 750 millimetres (30 in).[18][23]

Taupō Volcanic Zone, New Zealand[edit]

The Taupō Volcanic Zone is located on New Zealand's North Island. It is 350 kilometres (217 mi) long by 50 km wide (31 mi) and lies over a subduction zone in the Earth's crust. Mount Ruapehu marks its southwestern end, while the submarine Whakatāne seamount (85 km or 53 mi beyond Whakaari / White Island) is considered its northeastern limit.[24] Many geysers in this zone were destroyed due to geothermal developments and a hydroelectric reservoir, but several dozen geysers still exist.

In the beginning of the 20th century, the largest geyser ever known, the Waimangu Geyser existed in this zone. It began erupting in 1900 and erupted periodically for four years until a landslide changed the local water table. Eruptions of Waimangu would typically reach 160 metres (520 ft) and some superbursts are known to have reached 500 metres (1,600 ft).[18] Recent scientific work indicates that the Earth's crust below the zone may be as little as five kilometres (3.1 mi) thick. Beneath this lies a film of magma 50 kilometres (30 mi) wide and 160 kilometres (100 mi) long.[25]

Iceland[edit]

Due to the high rate of volcanic activity in Iceland, it is home to some of the most famous geysers in the world. There are around 20–29 active geysers in the country as well as numerous formerly active geysers.[26] Icelandic geysers are distributed in the zone stretching from south-west to north-east, along the boundary between the Eurasian Plate and the North American Plate. Most of the Icelandic geysers are comparatively short-lived, it is also characteristic that many geysers here are reactivated or newly created after earthquakes, becoming dormant or extinct after some years or some decades.

Two most prominent geysers of Iceland are located in Haukadalur. The Great Geysir, which first erupted in the 14th century, gave rise to the word geyser. By 1896, Geysir was almost dormant before an earthquake that year caused eruptions to begin again, occurring several times a day, but in 1916, eruptions all but ceased. Throughout much of the 20th century, eruptions did happen from time to time, usually following earthquakes. Some man-made improvements were made to the spring and eruptions were forced with soap on special occasions. Earthquakes in June 2000 subsequently reawakened the giant for a time but it is not currently erupting regularly. The nearby Strokkur geyser erupts every 5–8 minutes to a height of some 30 metres (98 ft).[18][27]

Geysers are known to have existed in at least a dozen other areas on the island. Some former geysers have developed historical farms, which benefitted from the use of the hot water since medieval times.

Extinct and dormant geyser fields[edit]

There used to be two large geysers fields in NevadaBeowawe and Steamboat Springs—but they were destroyed by the installation of nearby geothermal power plants. At the plants, geothermal drilling reduced the available heat and lowered the local water table to the point that geyser activity could no longer be sustained.[18]

Many of New Zealand's geysers have been destroyed by humans in the last century. Several New Zealand geysers have also become dormant or extinct by natural means. The main remaining field is Whakarewarewa at Rotorua.[28] Two thirds of the geysers at Orakei Korako were flooded by the construction of the hydroelectric Ohakuri dam in 1961.[29] The Wairakei field was lost to a geothermal power plant in 1958.[30] The Rotomahana field was destroyed by the 1886 eruption of Mount Tarawera.[31][32]

Misnamed geysers[edit]

There are various other types of geysers which are different in nature compared to the normal steam-driven geysers. These geysers differ not only in their style of eruption but also in the cause that makes them erupt.

Artificial geysers[edit]

In a number of places where there is geothermal activity, wells have been drilled and fitted with impermeable casements that allow them to erupt like geysers. The vents of such geysers are artificial, but are tapped into natural hydrothermal systems. These so-called artificial geysers, technically known as erupting geothermal wells, are not true geysers. Little Old Faithful Geyser, in Calistoga, California, is an example. The geyser erupts from the casing of a well drilled in the late 19th century. According to Dr. John Rinehart in his book A Guide to Geyser Gazing (1976 p. 49), a man had drilled into the geyser in search for water. He had "simply opened up a dead geyser".[33]

In the case of the Big Mine Run Geyser in Ashland, Pennsylvania, the heat powering the geyser (which erupts from an abandoned mine vent) comes not from geothermal power, but from the long-simmering Centralia mine fire.[34]

Perpetual spouter[edit]

This is a natural hot spring that spouts water constantly without stopping for recharge. Some of these are incorrectly called geysers, but because they are not periodic in nature they are not considered true geysers.[35][better source needed]

Commercialization[edit]

Bystanders watch a nearby geyser erupting.
The geyser Strokkur in Iceland – a tourist spot.

Geysers are used for various activities such as electricity generation, heating and tourism. Many geothermal reserves are found all around the world. The geyser fields in Iceland are some of the most commercially viable geyser locations in the world. Since the 1920s hot water directed from the geysers has been used to heat greenhouses and to grow food that otherwise could not have been cultivated in Iceland's inhospitable climate. Steam and hot water from the geysers has also been used for heating homes since 1943 in Iceland. In 1979 the U.S. Department of Energy (DOE) actively promoted development of geothermal energy in the "Geysers-Calistoga Known Geothermal Resource Area" (KGRA) near Calistoga, California through a variety of research programs and the Geothermal Loan Guarantee Program.[36] The Department is obligated by law to assess the potential environmental impacts of geothermal development.[37]

Extraterrestrial geyser-like features[edit]

There are many bodies in the Solar System where eruptions which superficially resemble terrestrial geysers have been observed or are believed to occur. Despite being commonly referred to as geysers, they are driven by fundamentally different processes, consist of a wide range of volatiles, and can occur on vastly disparate scales; from the modestly sized Martian carbon dioxide jets to the immense plumes of Enceladus. Generally, there are two broad categories of feature commonly referred to as geysers: sublimation plumes, and cryovolcanic plumes (also referred to as cryogeysers).

Sublimation plumes are jets of sublimated volatiles and dust from shallow sources under icy surfaces. Known examples include the CO2 jets on Mars, and the nitrogen eruptions on Neptune's moon Triton.

On Mars carbon dioxide jets are believed to occur in the southern polar region of Mars during spring, as a layer of dry ice accumulated over winter is warmed by the sun. Although these jets have not yet been directly observed, they leave evidence visible from orbit in the form of dark spots and lighter fans atop the dry ice. These features consist primarily of sand and dust blown out by the outbursts, as well as spider-like patterns of channels created below the ice by the rapid flow of CO2 gas.[38] There are a plethora of theories to explain the eruptions, including heating from sunlight, chemical reactions, or even biological activity.[39]

Triton was found to have active eruptions of nitrogen and dust by Voyager 2 when it flew past the moon in 1989. These plumes were up to 8 km high, where winds would blow them up to 150 km downwind, creating long, dark streaks across the otherwise bright south polar ice cap.[40] There are various theories as to what drives the activity on Triton, such as solar heating through transparent ice,[41] cryovolcanism, or basal heating of nitrogen ice sheets.[42]

Cryovolcanic plumes or cryogeysers generally refer to large-scale eruptions of predominantly water vapour from active cryovolcanic features on certain icy moons. Such plumes occur on Saturn's moon Enceladus and Jupiter's moon Europa.

Plumes of water vapour, together with ice particles and smaller amounts of other components (such as carbon dioxide, nitrogen, ammonia, hydrocarbons and silicates), have been observed erupting from vents associated with the "tiger stripes" in the south polar region of Enceladus by the Cassini orbiter. These plumes are the source of the material in Saturn's E ring. The mechanism which causes these eruptions are generated remains uncertain, as well as to what extent they are physically linked to Enceladus' subsurface ocean, but they are believed to be powered at least in part by tidal heating.[43] Cassini flew through these plumes several times, allowing direct analysis of water from inside another solar system body for the first time.[44]

In December 2013, the Hubble Space Telescope detected water vapor plumes potentially 200 km high above the south polar region of Europa.[45] Re-examination of Galileo data also suggested that it may have flown through a plume during a flyby in 1997.[46] Water was also detected by the Keck Observatory in 2016, announced in a 2019 Nature article speculating the cause to be a cryovolcanic eruption.[47] It is thought that Europa's lineae might be venting this water vapor into space in a similar manner to the "tiger stripes" of Enceladus.

Dark streaks deposited by plumes on Triton
Plumes erupting from Enceladus' subsurface
Artist's impression of the carbon dioxide jets on Mars

See also[edit]

Notes[edit]

  1. ^ "Definition of geyser noun from Cambridge Dictionary Online". Retrieved 2011-07-09.
  2. ^ "geyser | Definition of geyser in English by Oxford Dictionaries". Oxford Dictionaries | English. Archived from the original on June 9, 2013.
  3. ^ Bryan, T.S. 1995
  4. ^ a b "geyser | Definition of geyser in English by Lexico Dictionaries". Lexico Dictionaries | English. Archived from the original on July 5, 2019. Retrieved 2019-07-05.
  5. ^ "geyser | Origin and meaning of geyser by Online Etymology Dictionary". www.etymonline.com. Retrieved 2020-07-17.
  6. ^ a b c d How geysers form Gregory L.
  7. ^ Erickson, Jon (2014-05-14). Quakes, Eruptions, and Other Geologic Cataclysms: Revealing the Earth's Hazards. Infobase Publishing. ISBN 9781438109695.
  8. ^ a b c d Krystek, Lee. "Weird Geology: Geysers]". Museum of Unnatural Mystery. Retrieved 2008-03-28.
  9. ^ Lewin, Sarah (2015). "Instant Egghead: How do geysers erupt over and over?". Scientific American. 312 (5): 27. doi:10.1038/scientificamerican0515-27. PMID 26336706. Retrieved 2015-05-17.
  10. ^ "Yellowstone thermal features". Yahoo!. 2008-04-02. Archived from the original on November 16, 2007.
  11. ^ Brown, Sabrina (2019). Diatom-inferred records of paleolimnological variability and continental hydrothermal activity in Yellowstone National Park, USA (PhD dissertation). University of Nebraska–Lincoln.
  12. ^ Pasvanoglu, S.; Kristmannsdóttir, H.; Björnsson, S.; Torfason, H. (2000). "Geochemical Study of the Geysir Geothermal Field in Haukadalur, S. Iceland". Proceedings World Geothermal Congress 2000.
  13. ^ a b Lethe E. Morrison, Fred W. Tanner; Studies on Thermophilic Bacteria Botanical Gazette, Vol. 77, No. 2 (Apr., 1924), pp. 171–185
  14. ^ Michael T. Madigan and Barry L. Marrs; Extremophiles Archived 2008-04-09 at the Wayback Machine atropos.as.arizona.edu Retrieved on 2008-04-01
  15. ^ Vielle, C.; Zeikus, G.J. Hyperthermophilic Enzymes: Sources, Uses, and Molecular Mechanisms for Thermostability. Microbiology and Molecular Biology Reviews. 2001, 65(1), 1–34.
  16. ^ Industrial Uses of Thermophilic Cellulase University of Delaware, Retrieved on 2008-03-29 Archived October 10, 2007, at the Wayback Machine
  17. ^ Glennon, J.A. and Pfaff R.M. 2003; Bryan 1995
  18. ^ a b c d e f Glennon, J Allan "World Geyser Fields" Archived 2007-06-30 at the Wayback Machine Retrieved on 2008-04-04
  19. ^ "Yellowstone geysers" nps.gov Retrieved on 2008-03-20
  20. ^ Mehta, Aalok (2008-04-16). "Photo in the News: Russia's Valley of the Geysers Lost in Landslide". National Geographic. Archived from the original on June 17, 2007. Retrieved 2007-06-07.
  21. ^ Harding, Luke (2007-06-05). "Mudslide fully changes terrain in Kamchatka's Valley of Geysers". Guardian Unlimited. Retrieved 2008-04-16.
  22. ^ Shpilenok, Igor (2007-06-09). "June 2007 Special release – The Natural Disaster at the Valley of the Geysers". Archived from the original on April 12, 2008. Retrieved 2008-04-16.
  23. ^ Glennon, J.A. and Pfaff. R.M., 2003
  24. ^ Gamble, J. A.; Wright, I. C.; Baker, J. A. (1993). "Seafloor geology and petrology in the oceanic to continental transition zone of the Kermadec-Havre-Taupo Volcanic Zone arc system, New Zealand". New Zealand Journal of Geology and Geophysics. 36 (4): 417–435. doi:10.1080/00288306.1993.9514588. Archived from the original on 2008-11-22.
  25. ^ Central North Island sitting on magma film Archived 2009-01-07 at the Wayback Machine Paul Easton, The Dominion Post, 15 September 2007. Retrieved 2008-04-16
  26. ^ "Geysers of Iceland". 5 October 2019. Retrieved 8 October 2019.
  27. ^ Gardner Servian, Solveig "Geysers of Iceland" Retrieved on 2008-04-16
  28. ^ "Whakarewarewa, The Thermal Village" Retrieved 2008-04-04
  29. ^ "Orakeikorako". www.waikatoregion.govt.nz. Retrieved 2020-05-23.
  30. ^ "Yellowstone Supervolcano Could Be an Energy Source. But Should It?". Science. 2018-08-08. Archived from the original on August 8, 2018. Retrieved 2020-05-23.
  31. ^ Valley, Waimangu Volcanic. "1886 Mt Tarawera Eruption". Waimangu Volcanic Valley. Archived from the original on 2020-05-15. Retrieved 2020-05-23.
  32. ^ Klemetti, Erik (2011-02-10). "The 1886 Eruption of Mt. Tarawera, New Zealand". Wired. ISSN 1059-1028. Retrieved 2020-05-23.
  33. ^ Jones, Wyoming "Old Faithful Geyser of California" Archived 2019-06-07 at the Wayback Machine WyoJones' Geyser Pages Retrieved on 2008-03-31
  34. ^ Albert, Jessica (June 17, 2018). "Getting to the Bottom of This Gushing Geyser in Schuylkill County". WNEP-TV. Retrieved December 7, 2021.
  35. ^ WyoJones "Thermal Feature Definitions" Archived 2019-07-21 at the Wayback Machine WyoJones Retrieved on 2008-04-03
  36. ^ O'Banion, K.; Hall, C. (14 July 1980). "Geothermal energy and the land resource: conflicts and constraints in The Geysers". Calistoga KGRA. DOE–SciTech. doi:10.2172/6817678. OSTI 6817678. S2CID 129626036.
  37. ^ Kerry O’Banion and Charles Hall Geothermal energy and the land resource: conflicts and constraints in The Geysers- Calistoga KGRA osti.gov Retrieved on 2008-04-12
  38. ^ Burnham, Robert (2006-08-16). "Gas jet plumes unveil mystery of 'spiders' on Mars". Arizona State University web site. Retrieved 2009-08-29.
  39. ^ Horváth, A.; Gánti, T.; Gesztesi, A.; Bérczi, Sz.; Szathmáry, E. (2001-03-01). "Probable Evidences of Recent Biological Activity on Mars: Appearance and Growing of Dark Dune Spots in the South Polar Region". Lunar and Planetary Science: 1543.
  40. ^ Soderblom, L. A.; Kieffer, S. W.; Becker, T. L.; Brown, R. H.; Cook, A. F.; Hansen, C. J.; Johnson, T. V.; Kirk, R. L.; Shoemaker, E. M. (1990-10-19). "Triton's Geyser-Like Plumes: Discovery and Basic Characterization". Science. 250 (4979): 410–415. doi:10.1126/science.250.4979.410. ISSN 0036-8075.
  41. ^ Kirk, R.L., Branch of Astrogeology "Thermal Models of Insolation-driven Nitrogen Geysers on Triton" Harvard Retrieved 2008-04-08
  42. ^ Hofgartner, Jason D.; Birch, Samuel P. D.; Castillo, Julie; Grundy, Will M.; Hansen, Candice J.; Hayes, Alexander G.; Howett, Carly J. A.; Hurford, Terry A.; Martin, Emily S.; Mitchell, Karl L.; Nordheim, Tom A.; Poston, Michael J.; Prockter, Louise M.; Quick, Lynnae C.; Schenk, Paul (2022-03-15). "Hypotheses for Triton's plumes: New analyses and future remote sensing tests". Icarus. 375: 114835. arXiv:2112.04627. doi:10.1016/j.icarus.2021.114835. ISSN 0019-1035.
  43. ^ Porco, C. C.; Helfenstein, P.; Thomas, P. C.; Ingersoll, A. P.; Wisdom, J.; West, R.; Neukum, G.; Denk, T.; Wagner, R. (10 March 2006). "Cassini Observes the Active South Pole of Enceladus". Science. 311 (5766): 1393–1401. Bibcode:2006Sci...311.1393P. doi:10.1126/science.1123013. PMID 16527964. S2CID 6976648.
  44. ^ Waite, J. Hunter; Combi, Michael R.; Ip, Wing-Huen; Cravens, Thomas E.; McNutt, Ralph L.; Kasprzak, Wayne; Yelle, Roger; Luhmann, Janet; Niemann, Hasso; Gell, David; Magee, Brian; Fletcher, Greg; Lunine, Jonathan; Tseng, Wei-Ling (2006-03-10). "Cassini Ion and Neutral Mass Spectrometer: Enceladus Plume Composition and Structure". Science. 311 (5766): 1419–1422. doi:10.1126/science.1121290. ISSN 0036-8075.
  45. ^ Cook, Jia-Rui C.; Gutro, Rob; Brown, Dwayne; Harrington, J.D.; Fohn, Joe (12 December 2013). "Hubble Sees Evidence of Water Vapor at Jupiter Moon". NASA.
  46. ^ Jia, Xianzhe; Kivelson, Margaret G.; Khurana, Krishan K.; Kurth, William S. (June 2018). "Evidence of a plume on Europa from Galileo magnetic and plasma wave signatures". Nature Astronomy. 2 (6): 459–464. doi:10.1038/s41550-018-0450-z. ISSN 2397-3366.
  47. ^ Paganini, L.; Villanueva, G. L.; Roth, L.; Mandell, A. M.; Hurford, T. A.; Retherford, K. D.; Mumma, M. J. (March 2020). "A measurement of water vapour amid a largely quiescent environment on Europa". Nature Astronomy. 4 (3): 266–272. doi:10.1038/s41550-019-0933-6. ISSN 2397-3366.

References[edit]

External links[edit]