HiWish program

HiWish is a program created by NASA so that anyone can suggest a place for the HiRISE camera on the Mars Reconnaissance Orbiter to photograph.[1] It was started in January 2010. In the first few months of the program 3000 people signed up to use HiRISE.[2][3] The first images were released in April 2010.[4] Over 7000 suggestions were made by the public; suggestions were made for targets in each of the 30 quadrangles of Mars. Selected images released were used for three talks at the 16th Annual International Mars Society Convention. Below are some of the over 4,224 images that have been released from the HiWish program as of March, 2016.[5]

Glacial features

Some landscapes look just like glaciers moving out of mountain valleys on Earth. Some have a hollowed-out appearance, looking like a glacier after almost all the ice has disappeared. What is left are the moraines—the dirt and debris carried by the glacier. The center is hollowed out because the ice is mostly gone.[6] These supposed alpine glaciers have been called glacier-like forms (GLF) or glacier-like flows (GLF).[7] Glacier-like forms are a later and maybe more accurate term because we cannot be sure the structure is currently moving.[8]

Main article: Glaciers on Mars

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Martian glacier moving down a valley, as seen by HiRISE under HiWish program.

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Possible pingos

The radial and concentric cracks visible here are common when forces penetrate a brittle layer, such as a rock thrown through a glass window. These particular fractures were probably created by something emerging from below the brittle Martian surface. Ice may have accumulated under the surface in a lens shape; thus making these cracked mounds. Ice being less dense than rock, pushed upwards on the surface and generated these spider web-like patterns. A similar process creates similar sized mounds in arctic tundra on Earth. Such features are called “pingos,”, an Inuit word.[9] Pingos would contain pure water ice; thus they could be sources of water for future colonists of Mars.

Ancient rivers and streams

There is great deal of evidence that water once flowed in river valleys on Mars. Pictures from orbit show winding valleys, branched valleys, and even meanders with oxbow lakes.[10] Some are visible in the pictures below.

Streamlined shapes

Streamlined shapes represent more evidence of past flowing water on Mars. Water shaped features into streamlined shapes.

New Crater

Sand dunes

Many locations on Mars have sand dunes. The dunes are covered by a seasonal carbon dioxide frost that forms in early autumn and remains until late spring. Many martian dunes strongly resemble terrestrial dunes but images acquired by the High-Resolution Imaging Science Experiment on the Mars Reconnaissance Orbiter have shown that martian dunes in the north polar region are subject to modification via grainflow triggered by seasonal CO2 sublimation, a process not seen on Earth. Many dunes are black because they are derived from the dark volcanic rock basalt. Extraterrestrial sand seas such as those found on Mars are referred to as "undae" from the Latin for waves.

Landing site

Some of the targets suggested became possible sites for a Rover Mission in 2020. The targets were in Firsoff (crater) and Holden Crater. These locations were picked as two of 26 locations considered for a mission that will look for signs of life and gather samples for a later return to Earth.[11][12][13]

Landscape features

Dark slope streaks

Layers

Many places on Mars show rocks arranged in layers. Rock can form layers in a variety of ways. Volcanoes, wind, or water can produce layers.[15] Layers can be hardened by the action of groundwater.

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Gullies

Martian gullies are small, incised networks of narrow channels and their associated downslope sediment deposits, found on the planet of Mars. They are named for their resemblance to terrestrial gullies. First discovered on images from Mars Global Surveyor, they occur on steep slopes, especially on the walls of craters. Usually, each gully has a dendritic alcove at its head, a fan-shaped apron at its base, and a single thread of incised channel linking the two, giving the whole gully an hourglass shape.[16] They are believed to be relatively young because they have few, if any craters.

On the basis of their form, aspects, positions, and location amongst and apparent interaction with features thought to be rich in water ice, many researchers believed that the processes carving the gullies involve liquid water. However, this remains a topic of active research.

Main article: Martian gullies

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Image of gullies with main parts labeled. The main parts of a Martian gully are alcove, channel, and apron. Since there are no craters on this gully, it is thought to be rather young. Picture was taken by HiRISE under HiWish program. Location is Phaethontis quadrangle.

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Latitude dependent mantle

Much of the Martian surface is covered with a thick ice-rich, mantle layer that has fallen from the sky a number of times in the past.[17][18][19] In some places a number of layers are visible in the mantle.

It fell as snow and ice-coated dust. There is good evidence that this mantle is ice-rich. The shapes of the polygons common on many surfaces suggest ice-rich soil. High levels of hydrogen (probably from water) have been found with Mars Odyssey.[20][21][22][23][24] Thermal measurements from orbit suggest ice.[25][26] The Phoenix (spacecraft) discovered water ice with made direct observations since it landed in a field of polygons.[27][28] In fact, its landing rockets exposed pure ice. Theory had predicted that ice would be found under a few cm of soil. This mantle layer is called "latitude dependent mantle" because its occurrence is related to the latitude. It is this mantle that cracks and then forms polygonal ground. This cracking of ice-rich ground is predicted based on physical processes.[29][30] [31][32][33][34][35]

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Polygonal patterned ground

Polygonal, patterned ground is quite common in some regions of Mars.[36][37][38][39][40][41][42] It is commonly believed to be caused by the sublimation of ice from the ground. Sublimation is the direct change of solid ice to a gas. This is similar to what happens to dry ice on the Earth. Places on Mars that display polygonal ground may indicate where future colonists can find water ice. Patterned ground forms in a mantle layer, called latitude dependent mantle, that fell from the sky when the climate was different.[17][18][43][44]

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Scalloped topography

Scalloped topography is common in the mid-latitudes of Mars, between 45° and 60° north and south. It is particularly prominent in the region of Utopia Planitia[45][46] in the northern hemisphere and in the region of Peneus and Amphitrites Patera[47][48] in the southern hemisphere. Such topography consists of shallow, rimless depressions with scalloped edges, commonly referred to as "scalloped depressions" or simply "scallops". Scalloped depressions can be isolated or clustered and sometimes seem to coalesce. A typical scalloped depression displays a gentle equator-facing slope and a steeper pole-facing scarp. This topographic asymmetry is probably due to differences in insolation. Scalloped depressions are believed to form from the removal of subsurface material, possibly interstitial ice, by sublimation. This process may still be happening at present.[49]

On November 22, 2016, NASA reported finding a large amount of underground ice in the Utopia Planitia region of Mars.[50]The volume of water detected has been estimated to be equivalent to the volume of water in Lake Superior.[51][52] The volume of water ice in the region were based on measurements from the ground-penetrating radar instrument on Mars Reconnaissance Orbiter, called SHARAD. From the data obtained from SHARAD, “dielectric permittivity”, or the dielectric constant was determined. The dielectric constant value was consistent with a large concentration of water ice. [53] [54] [55]


Main article: Scalloped topography

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Pedestal Craters

A pedestal crater is a crater with its ejecta sitting above the surrounding terrain and thereby forming a raised platform (like a pedestal). They form when an impact crater ejects material which forms an erosion-resistant layer, thus causing the immediate area to erode more slowly than the rest of the region. Some pedestals have been accurately measured to be hundreds of meters above the surrounding area. This means that hundreds of meters of material were eroded away. The result is that both the crater and its ejecta blanket stand above the surroundings. Pedestal craters were first observed during the Mariner missions.[56][57][58][59]

Main article: Pedestal crater

Ring mold craters

Ring mold craters are believed to be formed from asteroid impacts into ground that has an underlying layer of ice. The impact produces an rebound of the ice layer to form a "ring-mold" shape.

Main article: Ring mold crater

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Halo Craters

Boulders

Dust devil tracks

Dust devil tracks can be very pretty. They are caused by giant dust devils removing bright colored dust from the Martian surface; thereby exposing a dark layer.

Yardangs

Yardangs are common in some regions on Mars, especially in what's called the "Medusae Fossae Formation." This formation is found in the Amazonis quadrangle and near the equator.[61] They are formed by the action of wind on sand sized particles; hence they often point in the direction that the winds were blowing when they were formed.[62] Because they exhibit very few impact craters they are believed to be relatively young.[63]

Main article: Yardangs on Mars

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Upper Plains Unit

Remnants of a 50-100 meter thick mantling, called the upper plains unit, has been discovered in the mid-latitudes of Mars. First investigated in the Deuteronilus Mensae (Ismenius Lacus quadrangle) region, but it occurs in other places as well. The remnants consist of sets of dipping layers in craters and along mesas.[64] Sets of dipping layers may be of various sizes and shapes—some look like Aztec pyramids from Central America

This unit also degrades into brain terrain. Brain terrain is a region of maze-like ridges 3–5 meters high. Some ridges may consist of an ice core, so they may be sources of water for future colonists.

Some regions of the upper plains unit display large fractures and troughs with raised rims; such regions are called ribbed upper plains. Fractures are believed to have started with small cracks from stresses. Stress is suggested to initiate the fracture process since ribbed upper plains are common when debris aprons come together or near the edge of debris aprons—such sites would generate compressional stresses. Cracks exposed more surfaces, and consequently more ice in the material sublimates into the planet's thin atmosphere. Eventually, small cracks become large canyons or troughs.

Small cracks often contain small pits and chains of pits; these are thought to be from sublimation (phase transition) of ice in the ground.[65][66] Large areas of the Martian surface are loaded with ice that is protected by a meters thick layer of dust and other material. However, if cracks appear, a fresh surface will expose ice to the thin atmosphere.[67][68] In a short time, the ice will disappear into the cold, thin atmosphere in a process called sublimation (phase transition). Dry ice behaves in a similar fashion on the Earth. On Mars sublimation has been observed when the Phoenix lander uncovered chunks of ice that disappeared in a few days.[27][69] In addition, HiRISE has seen fresh craters with ice at the bottom. After a time, HiRISE saw the ice deposit disappear.[70]

The upper plains unit is thought to have fallen from the sky. It drapes various surfaces, as if it fell evenly. As is the case for other mantle deposits, the upper plains unit has layers, is fine-grained, and is ice-rich. It is widespread; it does not seem to have a point source. The surface appearance of some regions of Mars is due to how this unit has degraded. It is a major cause of the surface appearance of lobate debris aprons.[66] The layering of the upper plains mantling unit and other mantling units are believed to be caused by major changes in the planet's climate. Models predict that the obliquity or tilt of the rotational axis has varied from its present 25 degrees to maybe over 80 degrees over geological time. Periods of high tilt will cause the ice in the polar caps to be redistributed and change the amount of dust in the atmosphere.[71][72][73]

Linear Ridge Networks

Linear ridge networks are found in various places on Mars in and around craters.[74] Ridges often appear as mostly straight segments that intersect in a lattice-like manner. They are hundreds of meters long, tens of meters high, and several meters wide. It is thought that impacts created fractures in the surface, these fractures later acted as channels for fluids. Fluids cemented the structures. With the passage of time, surrounding material was eroded away, thereby leaving hard ridges behind. Since the ridges occur in locations with clay, these formations could serve as a marker for clay which requires water for its formation.[75][76][77] Water here could have supported

Mesas

Mesas formed by ground collapse

Fractures forming blocks

In places large fractures break up surfaces. Sometimes straight edges are formed and large cubes are created by the fractures.

Lava flows

Rootless Cones

So-called "Rootless cones" are caused by explosions of lava with ground ice under the flow. The ice melts and turns into a vapor that expands in an explosion that produces a cone or ring. Featureslike these are found in Iceland, when lavas cover water-saturated substrates.[78][79][80]

Mud volcanoes

Some features look like volcanoes. Some of them may be mud volcanoes where pressurized mud is forced upward forming cones. These features may be places to look for life as they bring to the surface possible life that has been protected from radiation.

How to suggest image

To suggest a location for HiRISE to image visit the site at http://www.uahirise.org/hiwish

In the sign up process you will need to come up with an ID and a password. When you choose a target to be imaged, you have to pick and exact location on a map and write about why the image should be taken. If you suggestion is accepted, it may take 3 months or more to see your image. You will be sent an email telling you about your images. The emails usually arrive on the first Wednesday of the month in the late afternoon.

See also

References

  1. "Public Invited To Pick Pixels On Mars". Mars Daily. January 22, 2010. Retrieved January 10, 2011.
  2. Interview with Alfred McEwen on Planetary Radio, 3/15/2010
  3. http://www.planetary.org/multimedia/planetary-radio/show/2010/384.html
  4. "NASA releases first eight "HiWish" selections of people's choice Mars images". TopNews. April 2, 2010. Retrieved January 10, 2011.
  5. McEwen, A. et al. 2016. THE FIRST DECADE OF HIRISE AT MARS. 47th Lunar and Planetary Science Conference (2016) 1372.pdf
  6. Milliken, R., J. Mustard, D. Goldsby. 2003. Viscous flow features on the surface of Mars: Observations from high-resolution Mars Orbiter Camera (MOC) images. J. Geophys. Res. 108. doi:10.1029/2002JE002005.
  7. Arfstrom, J and W. Hartmann. 2005. Martian flow features, moraine-like ridges, and gullies: Terrestrial analogs and interrelationships. Icarus 174, 321-335.
  8. Hubbard B., R. Milliken, J. Kargel, A. Limaye, C. Souness. 2011. Geomorphological characterisation and interpretation of a mid-latitude glacier-like form: Hellas Planitia, Mars Icarus 211, 330–346
  9. http://www.uahirise.org/ESP_046359_1250
  10. Baker, V. 1982. The Channels of Mars. Univ. of Tex. Press, Austin, TX
  11. http://marsnext.jpl.nasa.gov/workshops/index.cfm
  12. http://hirise.lpl.arizona.edu/ESP_039404_1820
  13. Pondrelli, M., A. Rossi, L. Deit, S. van Gasselt, F. Fueten, E. Hauber, B. Cavalazzi, M. Glamoclija, and F. Franchi. 2014. A PROPOSED LANDING SITE FOR THE 2020 MARS MISSION: FIRSOFF CRATER. http://marsnext.jpl.nasa.gov/workshops/2014_05/33_Pondrelli_Firsoff_LS2020.pdf
  14. Golombek, J. et al. 2016. Downselection of landing Sites for the Mars 2020 Rover Mission. 47th Lunar and Planetary Science Conference (2016). 2324.pdf
  15. "HiRISE | High Resolution Imaging Science Experiment". Hirise.lpl.arizona.edu?psp_008437_1750. Retrieved 2012-08-04.
  16. Malin, M., Edgett, K. 2000. Evidence for recent groundwater seepage and surface runoff on Mars. Science 288, 2330–2335.
  17. 1 2 Hecht, M. 2002. Metastability of water on Mars. Icarus 156, 373–386
  18. 1 2 Mustard, J., et al. 2001. Evidence for recent climate change on Mars from the identification of youthful near-surface ground ice. Nature 412 (6845), 411–414.
  19. Pollack, J., D. Colburn, F. Flaser, R. Kahn, C. Carson, and D. Pidek. 1979. Properties and effects of dust suspended in the martian atmosphere. J. Geophys. Res. 84, 2929-2945.
  20. Boynton, W., and 24 colleagues. 2002. Distribution of hydrogen in the nearsurface of Mars: Evidence for sub-surface ice deposits. Science 297, 81–85
  21. Kuzmin, R, et al. 2004. Regions of potential existence of free water (ice) in the near-surface martian ground: Results from the Mars Odyssey High-Energy Neutron Detector (HEND). Solar System Research 38 (1), 1–11.
  22. Mitrofanov, I. et al. 2007a. Burial depth of water ice in Mars permafrost subsurface. In: LPSC 38, Abstract #3108. Houston, TX.
  23. Mitrofanov, I., and 11 colleagues. 2007b. Water ice permafrost on Mars: Layering structure and subsurface distribution according to HEND/Odyssey and MOLA/ MGS data. Geophys. Res. Lett. 34 (18). doi:10.1029/2007GL030030.
  24. Mangold, N., et al. 2004. Spatial relationships between patterned ground and ground ice detected by the neutron spectrometer on Mars. J. Geophys. Res. 109 (E8). doi:10.1029/ 2004JE002235.
  25. Feldman, W., and 12 colleagues. 2002. Global distribution of neutrons from Mars: Results from Mars Odyssey. Science 297, 75–78.
  26. Feldman, W., et al. 2008. North to south asymmetries in the water-equivalent hydrogen distribution at high latitudes on Mars. J. Geophys. Res. 113. doi:10.1029/2007JE003020.
  27. 1 2 Bright Chunks at Phoenix Lander's Mars Site Must Have Been Ice – Official NASA press release (19.06.2008)
  28. "Confirmation of Water on Mars". Nasa.gov. 2008-06-20. Retrieved 2012-07-13.
  29. Mutch, T.A., and 24 colleagues, 1976. The surface of Mars: The view from the Viking2 lander. Science 194 (4271), 1277–1283.
  30. Mutch, T., et al. 1977. The geology of the Viking Lander 2 site. J. Geophys. Res. 82, 4452–4467.
  31. Levy, J., et al. 2009. Thermal contraction crack polygons on Mars: Classification, distribution, and climate implications from HiRISE observations. J. Geophys. Res. 114. doi:10.1029/2008JE003273.
  32. Washburn, A. 1973. Periglacial Processes and Environments. St. Martin's Press, New York, pp. 1–2, 100–147.
  33. Mellon, M. 1997. Small-scale polygonal features on Mars: Seasonal thermal contraction cracks in permafrost. J. Geophys. Res. 102, 25,617-625,628.
  34. Mangold, N. 2005. High latitude patterned grounds on Mars: Classification, distribution and climatic control. Icarus 174, 336–359.
  35. Marchant, D., J. Head. 2007. Antarctic dry valleys: Microclimate zonation, variable geomorphic processes, and implications for assessing climate change on Mars. Icarus 192, 187–222
  36. http://www.diss.fu-berlin.de/diss/servlets/MCRFileNodeServlet/FUDISS_derivate_000000003198/16_ColdClimateLandforms-13-utopia.pdf?hosts=
  37. Kostama, V.-P., M. Kreslavsky, Head, J. 2006. Recent high-latitude icy mantle in the northern plains of Mars: Characteristics and ages of emplacement. Geophys. Res. Lett. 33 (L11201). doi:10.1029/2006GL025946. K
  38. Malin, M., Edgett, K. 2001. Mars Global Surveyor Mars Orbiter Camera: Interplanetary cruise through primary mission. J. Geophys. Res. 106 (E10), 23429–23540.
  39. Milliken, R., et al. 2003. Viscous flow features on the surface of Mars: Observations from high-resolution Mars Orbiter Camera (MOC) images. J. Geophys. Res. 108 (E6). doi:10.1029/2002JE002005.
  40. Mangold, N. 2005. High latitude patterned grounds on Mars: Classification, distribution and climatic control. Icarus 174, 336–359.
  41. Kreslavsky, M., Head, J. 2000. Kilometer-scale roughness on Mars: Results from MOLA data analysis. J. Geophys. Res. 105 (E11), 26695–26712.
  42. Seibert, N., J. Kargel. 2001. Small-scale martian polygonal terrain: Implications for liquid surface water. Geophys. Res. Lett. 28 (5), 899–902. S
  43. Kreslavsky, M.A., Head, J.W., 2002. High-latitude Recent Surface Mantle on Mars: New Results from MOLA and MOC. European Geophysical Society XXVII, Nice.
  44. Head, J.W., Mustard, J.F., Kreslavsky, M.A., Milliken, R.E., Marchant, D.R., 2003. Recent ice ages on Mars. Nature 426 (6968), 797–802.
  45. Lefort, A.; Russell, P. S.; Thomas, N.; McEwen, A. S.; Dundas, C. M.; Kirk, R. L. (2009). "Observations of periglacial landforms in Utopia Planitia with the High Resolution Imaging Science Experiment (HiRISE)". Journal of Geophysical Research. 114 (E4). Bibcode:2009JGRE..11404005L. doi:10.1029/2008JE003264.
  46. Morgenstern, A; Hauber, E; Reiss, D; van Gasselt, S; Grosse, G; Schirrmeister, L (2007). "Deposition and degradation of a volatile-rich layer in Utopia Planitia, and implications for climate history on Mars" (PDF). Journal of Geophysical Research: Planets. 112 (E6): E06010. Bibcode:2007JGRE..11206010M. doi:10.1029/2006JE002869.
  47. Lefort, A.; Russell, P.S.; Thomas, N. (2010). "Scalloped terrains in the Peneus and Amphitrites Paterae region of Mars as observed by HiRISE". Icarus. 205 (1): 259. Bibcode:2010Icar..205..259L. doi:10.1016/j.icarus.2009.06.005.
  48. Zanetti, M.; Hiesinger, H.; Reiss, D.; Hauber, E.; Neukum, G. (2009). "Scalloped Depression Development on Malea Planum and the Southern Wall of the Hellas Basin, Mars" (PDF). Lunar and Planetary Science. 40. p. 2178, abstract 2178. Bibcode:2009LPI....40.2178Z.
  49. http://hiroc.lpl.arizona.edu/images/PSP?diafotizo.php?ID=PSP_002296_1215
  50. http://www.space.com/34811-mars-ice-more-water-than-lake-superior.html?utm_source=sp-newsletter&utm_medium=email&utm_campaign=20161123-sdc
  51. Staff (November 22, 2016). "Scalloped Terrain Led to Finding of Buried Ice on Mars". NASA. Retrieved November 23, 2016.
  52. "Lake of frozen water the size of New Mexico found on Mars – NASA". The Register. November 22, 2016. Retrieved November 23, 2016.
  53. Bramson, A, et al. 2015. Widespread excess ice in Arcadia Planitia, Mars. Geophysical Research Letters: 42, 6566-6574
  54. https://planetarycassie.com/2016/11/04/widespread-thick-water-ice-found-in-utopia-planitia-mars/
  55. Stuurman, C., et al. 2016. SHARAD detection and characterization of subsurface water ice deposits in Utopia Planitia, Mars. Geophysical Research Letters: 43, 9484_9491.
  56. http://hirise.lpl.eduPSP_008508_1870
  57. Bleacher, J. and S. Sakimoto. Pedestal Craters, A Tool For Interpreting Geological Histories and Estimating Erosion Rates. LPSC
  58. http://themis.asu.edu/feature_utopiacraters
  59. McCauley, J. F. (1973). "Mariner 9 evidence for wind erosion in the equatorial and mid-latitude regions of Mars". Journal of Geophysical Research. 78 (20): 4123–4137. Bibcode:1973JGR....78.4123M. doi:10.1029/JB078i020p04123.
  60. Levy, J. et al. 2008. Origin and arrangement of boulders on the martian northern plains: Assessment of emplacement and modification environments> In 39th Lunar and Planetary Science Conference, Abstract #1172. League City, TX
  61. SAO/NASA ADS Astronomy Abstract Service: Yardangs on Mars
  62. http://www.esa.int/Our_Activities/Space_Science/Mars_Express/Yardangs_on_Mars
  63. http://themis.asu.edu/zoom-20020416a
  64. Carr, M. 2001.
  65. Morgenstern, A., et al. 2007
  66. 1 2 Baker, D., J. Head. 2015. Extensive Middle Amazonian mantling of debris aprons and plains in Deuteronilus Mensae, Mars: Implication for the record of mid-latitude glaciation. Icarus: 260, 269-288.
  67. Mangold, N. 2003. Geomorphic analysis of lobate debris aprons on Mars at Mars Orbiter Camera scale: Evidence for ice sublimation initiated by fractures. J. Geophys. Res. 108, 8021.
  68. Levy, J. et al. 2009. Concentric
  69. http://www.nasa.gov/mission_pages/phoenix/news/phoenix-20080619.html
  70. Byrne, S. et al. 2009. Distribution of Mid-Latitude Ground Ice on Mars from New Impact Craters: 329.1674-1676
  71. Head, J. et al. 2003.
  72. Madeleine, et al. 2014.
  73. Schon, et al. 2009. A recent ice age on Mars: Evidence for climate oscillations from regional layering in mid-latitude mantling deposits. Geophys. Res. Lett. 36, L15202.
  74. Head, J., J. Mustard. 2006. Breccia dikes and crater-related faults in impact craters on Mars: Erosion and exposure on the floor of a crater 75 km in diameter at the dichotomy boundary, Meteorit. Planet Science: 41, 1675-1690.
  75. Mangold et al. 2007. Mineralogy of the Nili Fossae region with OMEGA/Mars Express data: 2. Aqueous alteration of the crust. J. Geophys. Res., 112, doi:10.1029/2006JE002835.
  76. Mustard et al., 2007. Mineralogy of the Nili Fossae region with OMEGA/Mars Express data: 1. Ancient impact melt in the Isidis Basin and implications for the transition from the Noachian to Hesperian, J. Geophys. Res., 112.
  77. Mustard et al., 2009. Composition, Morphology, and Stratigraphy of Noachian Crust around the Isidis Basin, J. Geophys. Res., 114, doi:10.1029/2009JE003349.
  78. S. Fagents1,A., P. Lanagan, R. Greeley. 2002. Rootless cones on Mars: a consequence of lava-ground ice interaction. Geological Society, Londo. Special Publications: 202, 295-317.
  79. http://www.psrd.hawaii.edu/June01/lavaIceMars.html
  80. Jaeger, W., L. Keszthelyi, A. McEwen, C. Dundas, P. Russell, and the HiRISE team. 2007. EARLY HiRISE OBSERVATIONS OF RING/MOUND LANDFORMS IN ATHABASCA VALLES, MARS. Lunar and Planetary Science XXXVIII 1955.pdf.
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