Glaciers on Mars - Revision history

Suitupshowup: added ref about glaciers in mountains

2025-06-02T19:29:34Z

added ref about glaciers in mountains

Suitupshowup: added new info and ref

2025-01-22T14:12:16Z

added new info and ref

Suitupshowup: /* Lineated Valley Fill */ added images

2024-10-05T15:03:20Z

Lineated Valley Fill: added images

Suitupshowup: /* Variety of Glaciers on Mars */ added ref

2024-01-01T23:26:03Z

Variety of Glaciers on Mars: added ref

Suitupshowup: /* External links */

2023-12-30T01:12:07Z

External links

Suitupshowup: /* External links */ added link

2023-12-30T01:11:43Z

External links: added link

Suitupshowup: added ref

2023-12-28T16:37:39Z

added ref

Suitupshowup: added ref

2023-12-28T16:35:27Z

added ref

Suitupshowup: /* Source of Ice */

2023-12-20T23:59:56Z

Source of Ice

Suitupshowup: /* Source of Ice */ added new info and ref

2023-12-20T23:58:55Z

Source of Ice: added new info and ref

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 </gallery>
-With better cameras, it was observed that some mesas had what resembled glaciers in the valleys.<ref>https://www.uahirise.org/hipod/ESP_077592_2225</ref>   A big advance in understanding Martian geology came when the Mars Orbiter Laser Altimeter (MOLA) on Mars Global Surveyor gave us exact elevations for the whole planet; from then on, we could figure out slopes.  Where the land was tilted, the glacier-forms moved down slope.   Also, researchers observed that when the glacier left the valley and reached a wider, flatter place, it spread out, just as glaciers on Earth do.  In some craters there are large glaciers shaped like giant tongues, so they have been called tongue-shaped glaciers. <ref>Forget, F., et al.  2006.  Planet Mars Story of Another World.  Praxis Publishing, Chichester, UK.   ISBN|978-0-387-48925-4</ref>
+With better cameras, it was observed that some mesas had what resembled glaciers in the valleys.<ref>https://www.uahirise.org/hipod/ESP_077592_2225</ref>   A big advance in understanding Martian geology came when the Mars Orbiter Laser Altimeter (MOLA) on Mars Global Surveyor gave us exact elevations for the whole planet; from then on, we could figure out slopes.  Where the land was tilted, the glacier-forms moved down slope.   Also, researchers observed that when the glacier left the valley and reached a wider, flatter place, it spread out, just as glaciers on Earth do.<ref> https://www.uahirise.org/hipod/PSP_008809_2215</ref>  In some craters there are large glaciers shaped like giant tongues, so they have been called tongue-shaped glaciers. <ref>Forget, F., et al.  2006.  Planet Mars Story of Another World.  Praxis Publishing, Chichester, UK.   ISBN|978-0-387-48925-4</ref>
 [[File:Mars_MGS_colorhillshade_mola_1024.jpg |thumb|300px|center|Topographic map produced with MOLA measurements  This map showed that glacial features move downhill.]]

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 Earth Planet. Sci. Lett., 294.  pp. 306-320</ref> <ref> D.M.H. Baker, J.W. Head, D.R. Marchant.  2010.  Flow patterns of lobate debris aprons and lineated valley fill north of Ismeniae fossae, Mars: evidence for extensive mid-latitude glaciation in the late Amazonian.  Icarus, 207 (2010), pp. 186-209, 10.1016/j.icarus.2009.11.017</ref> <ref>J.S. Levy, J.W. Head, D.R. Marchant.  2010.  Concentric crater fill in the northern mid-latitudes of Mars: formation processes and relationships to similar landforms of glacial origin.  Icarus.   209.   pp. 390-404, 10.1016/j.icarus.2010.03.036</ref>  Viscous Flow Features (VFF) is a general term that applies to all of these.<ref>https://www-sciencedirect-com.wikipedialibrary.idm.oclc.org/science/article/pii/S0019103520305091</ref> <ref>Berman, D., et al.  2021.  Ice-rich landforms of the southern mid-latitudes of Mars: A case study in Nereidum Monte.  Icarus.  Icarus.  Volume 355.  114170</ref> <ref>Milliken R.E., Mustard J.F., Goldsby D.L.
 Viscous flow features on the surface of Mars: Observations from high-resolution Mars Orbiter Camera (MOC) images
-J. Geophys. Res.: Planets, 108 (E6) (2003), p. 5057, 10.1029/2002je002005</ref>
+J. Geophys. Res.: Planets, 108 (E6) (2003), p. 5057, 10.1029/2002je002005</ref>   After years of observations, researchers consider lobate debris aprons (LDA's) and lineated valley fill (LVF) to be basically the same--mostly ice with a covering of debris, their shapes (and names) are dependent on their locations.  When confined within a valley, LVF is present; in contrast when not confined, this flowing debris covered ice spreads out to form LDA's.<ref>Wueller, L., et al.  2025.  Relationships between lobate debris aprons and lineated valley fill on Mars: Evidence for an extensive Amazonian valley glacial landsystem in Mamers Valles.  Icarus.  Volume 426, 15  116373</ref>
 ==Glaciers that look like glaciers==

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 <gallery class="center"  widths="380px" heights="360px">
 File:56544 2200lvfbrains.jpg|Wide view of Lineated Valley Fill
 File:56544 2200lvf.jpg|Close view of Lineated Valley Fill   The  location is the Ismenius Lacus quadrangle.

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 Today, we recognize several types of features that contain ice that is covered with dirt and rocks that keep the ice from disappearing.  These features behave like glaciers.  Concentric crater fill (CCF), lobate debris aprons (LDA), and lineated valley fill (LVF) are their names.
 <ref>https://www.sciencedirect.com.wikipedialibrary.idm.oclc.org/science/article/pii/S0019103520304619#bb0190</ref> <ref>Jawin, E, and J. Head.  2021.  Patterns of late Amazonian deglaciation from the distribution of martian paraglacial features. Icarus.  Volume 355. 114117</ref> <ref> S.W. Squyres.  1979.  The distribution of lobate debris aprons and similar flows on Mars.  J. Geophys. Res. Solid Earth, 84. pp. 8087-8096, 10.1029/JB084iB14p08087</ref> <ref>J.W. Head, G. Neukum, R. Jaumann, H. Hiesinger, E. Hauber, M. Carr, P. Masson, B. Foing, H. Hoffmann, M. Kreslavsky, S. Werner, S. Milkovich, S. van Gasselt, Co-Investigator Team, T.H.  2005.  Tropical to mid-latitude snow and ice accumulation, flow and glaciation on Mars.  Nature, 434. pp. 346-351</ref>  <ref>J.W. Head, D.R. Marchant, J.L. Dickson, A.M. Kress, D.M. Baker.  2010.  Northern mid-latitude glaciation in the late Amazonian period of Mars: criteria for the recognition of debris-covered glacier and valley glacier landsystem deposits
-Earth Planet. Sci. Lett., 294.  pp. 306-320</ref> <ref> D.M.H. Baker, J.W. Head, D.R. Marchant.  2010.  Flow patterns of lobate debris aprons and lineated valley fill north of Ismeniae fossae, Mars: evidence for extensive mid-latitude glaciation in the late Amazonian.  Icarus, 207 (2010), pp. 186-209, 10.1016/j.icarus.2009.11.017</ref> <ref>J.S. Levy, J.W. Head, D.R. Marchant.  2010.  Concentric crater fill in the northern mid-latitudes of Mars: formation processes and relationships to similar landforms of glacial origin.  Icarus.   209.   pp. 390-404, 10.1016/j.icarus.2010.03.036</ref>  Viscous Flow Features (VFF) is a general that applies to all of these.<ref>https://www-sciencedirect-com.wikipedialibrary.idm.oclc.org/science/article/pii/S0019103520305091</ref> <ref>Berman, D., et al.  2021.  Ice-rich landforms of the southern mid-latitudes of Mars: A case study in Nereidum Monte.  Icarus.  Icarus.  Volume 355.  114170</ref>
+Earth Planet. Sci. Lett., 294.  pp. 306-320</ref> <ref> D.M.H. Baker, J.W. Head, D.R. Marchant.  2010.  Flow patterns of lobate debris aprons and lineated valley fill north of Ismeniae fossae, Mars: evidence for extensive mid-latitude glaciation in the late Amazonian.  Icarus, 207 (2010), pp. 186-209, 10.1016/j.icarus.2009.11.017</ref> <ref>J.S. Levy, J.W. Head, D.R. Marchant.  2010.  Concentric crater fill in the northern mid-latitudes of Mars: formation processes and relationships to similar landforms of glacial origin.  Icarus.   209.   pp. 390-404, 10.1016/j.icarus.2010.03.036</ref>  Viscous Flow Features (VFF) is a general term that applies to all of these.<ref>https://www-sciencedirect-com.wikipedialibrary.idm.oclc.org/science/article/pii/S0019103520305091</ref> <ref>Berman, D., et al.  2021.  Ice-rich landforms of the southern mid-latitudes of Mars: A case study in Nereidum Monte.  Icarus.  Icarus.  Volume 355.  114170</ref> <ref>Milliken R.E., Mustard J.F., Goldsby D.L.
 ==Glaciers that look like glaciers==

@@ Line 143: / Line 143: @@
 *Baker, D. and L. Carter.  2019.  Probing supraglacial debris on Mars 1: Sources, thickness, and stratigraphy.  Icarus.  Volume 319.   Pages 745-769
- *Jawin, E.,et al.  2018.  Transient post-glacial processes on Mars: Geomorphologic evidence for a paraglacial period.  Icarus.  Volume 309.  Pages 187-206
+*Jawin, E.,et al.  2018.  Transient post-glacial processes on Mars: Geomorphologic evidence for a paraglacial period.  Icarus.  Volume 309.  Pages 187-206
 *Head, J., et al.  2023.  GEOLOGICAL AND CLIMATE HISTORY OF MARS: IDENTIFICATION OF POTENTIAL WARM AND

← Older revision		Revision as of 16:37, 28 December 2023
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−	Since the 60’s, as our spacecraft have studied Mars with more and more advanced cameras and other instruments, we have found more and more evidence for glaciers. <ref name="SquyresCarr">cite journal \| last1 = Squyres \| first1 = S.W. \| last2 = Carr \| first2 = M.H. \| year = 1986 \| title = Geomorphic evidence for the distribution of ground ice on Mars \| url = \| journal = Science \| volume = 213 \| issue = \| pages = 249–253 \| doi = 10.1126/science.231.4735.249 \| </ref> <ref name="Headetal2010">cite journal \| last1 = Head \| first1 = J.W. \| last2 = Marchant \| first2 = D.R. \| last3 = Dickson \| first3 = J.L. \| last4 = Kress \| first4 = A.M. \| year = 2010 \| title = Criteria for the recognition of debris-covered glacier and valley glacier landsystem deposits \| url = \| journal = Earth Planet. Sci. Lett. \| volume = 294 \| issue = \| pages = 306–320 \| doi=10.1016/j.epsl.2009.06.041 \| </ref> <ref name="HoltetalSHARAD">cite journal \| last1 = Holt \| first1 = J.W. \| display-authors = 1 \| last2 = et al \| year = 2008 \| title = Radar sounding evidence for buried glaciers in the southern mid-latitudes of Mars \| url = \| journal = Science \| volume = 322 \| issue = \| pages = 1235–1238 \| doi=10.1126/science.1164246 \| pmid=19023078\|</ref> <ref name="MorganetalDeuteronilus">\| last1 = Morgan \| first1 = G.A. \| last2 = Head \| first2 = J.W. \| last3 = Marchant \| first3 = D.R. \| year = 2009 \| title = Lineated valley fill (LVF) and lobate debris aprons (LDA) in the Deuteronilus Mensae northern dichotomy boundary region, Mars: Constraints on the extent, age and episodicity of Amazonian glacial events \| url = \| journal = Icarus \| volume = 202 \| issue = \| pages = 22–38 \| doi=10.1016/j.icarus.2009.02.017 \|</ref > <ref name="Plautetal">cite journal \| last1 = Plaut \| first1 = J.J. \| last2 = Safaeinili \| first2 = A. \| last3 = Holt \| first3 = J.W. \| last4 = Phillips \| first4 = R.J. \| last5 = Head \| first5 = J.W. \| last6 = Sue \| first6 = R. \| last7 = Putzig \| first7 = A. \| year = 2009 \| title = Frigeri Radar evidence for ice in lobate debris aprons in the mid-northern latitudes of Mars \| doi = 10.1029/2008gl036379 \| journal = Geophys. Res. Lett. \| volume = 36 \| issue = \| page = L02203 \| </ref> <ref name="Bakeretal2010">cite journal \| last1 = Baker \| first1 = D.M.H. \| last2 = Head \| first2 = J.W. \| last3 = Marchant \| first3 = D.R. \| year = 2010 \| title = Flow patterns of lobate debris aprons and lineated valley fill north of Ismeniae Fossae, Mars: Evidence for extensive mid-latitude glaciation in the Late Amazonian \| url = \| journal = Icarus \| volume = 207 \| issue = \| pages = 186–209 \| doi=10.1016/j.icarus.2009.11.017 \| </ref> <ref name="ArfstromHartmann">cite journal \| last1 = Arfstrom \| first1 = J. \| year = 2005 \| title = Terrestrial analogs and interrelationships \| url = \| journal = Icarus \| volume = 174 \| issue = \| pages = 321–335 \| doi=10.1016/j.icarus.2004.05.026 \| bibcode=2005Icar..174..321A</ref> On Mars these glaciers are covered with rock and dust debris a few meters to a few tens of meters thick. Although Mars today seems too dry for any glaciers, this covering material has protected the underlying ice. <ref name="WilliamsSnowpack">cite journal \| last1 = Williams \| first1 = K. E. \| display-authors = 1 \| last2 = et al \| year = 2008 \| title = Stability of mid-latitude snowpacks on Mars \| url = \| journal = Icarus \| volume = 196 \| issue = 2\| pages = 565–577 \| doi=10.1016/j.icarus.2008.03.017 \|</ref> One would think that under today’s conditions any exposed ice would undergo [[sublimation]] and disappear into the thin Martian atmosphere. That is, it would go directly from a solid to a gas. But, the isulating effect of surface material prevents loss of ice.<ref name="Plautetal" /> <ref name="WilliamsSnowpack" /> <ref name="Head, J. 2005">cite journal \| doi = 10.1038/nature03359 \| last1 = Head \| first1 = J. \| date = 2005 \| last2 = Neukum \| first2 = G. \| last3 = Jaumann \| first3 = R. \| last4 = Hiesinger \| first4 = H. \| last5 = Hauber \| first5 = E. \| last6 = Carr \| first6 = M. \| last7 = Masson \| first7 = P. \| last8 = Foing \| first8 = B. \| last9 = Hoffmann \| first9 = H. \| last10 = Kreslavsky \| first10 = M. \| last11 = Werner \| first11 = S. \| last12 = Milkovich \| first12 = S. \| last13 = Van Gasselt \| first13 = S. \| last14 = Co-Investigator Team \| first14 = The Hrsc \| title = Tropical to mid-latitude snow and ice accumulation, flow and glaciation on Mars \| url = \| journal=Nature \| volume = 434 \| issue = 7031\| pages = 346–350 \| pmid=15772652\|</ref> <ref> Head, J., et al. 2009. Northern mid-latitude glaciation in the Late Amazonian period of Mars: Criteria for the recognition of debris-covered glacier and valley glacier landsystem deposits. Earth and Planetary Science Letters. Doi:10.1016/j.epsl.2009.06.041</ref>	+	Since the 60’s, as our spacecraft have studied Mars with more and more advanced cameras and other instruments, we have found more and more evidence for glaciers. <ref name="SquyresCarr">cite journal \| last1 = Squyres \| first1 = S.W. \| last2 = Carr \| first2 = M.H. \| year = 1986 \| title = Geomorphic evidence for the distribution of ground ice on Mars \| url = \| journal = Science \| volume = 213 \| issue = \| pages = 249–253 \| doi = 10.1126/science.231.4735.249 \| </ref> <ref name="Headetal2010">cite journal \| last1 = Head \| first1 = J.W. \| last2 = Marchant \| first2 = D.R. \| last3 = Dickson \| first3 = J.L. \| last4 = Kress \| first4 = A.M. \| year = 2010 \| title = Criteria for the recognition of debris-covered glacier and valley glacier landsystem deposits \| url = \| journal = Earth Planet. Sci. Lett. \| volume = 294 \| issue = \| pages = 306–320 \| doi=10.1016/j.epsl.2009.06.041 \| </ref> <ref name="HoltetalSHARAD">cite journal \| last1 = Holt \| first1 = J.W. \| display-authors = 1 \| last2 = et al \| year = 2008 \| title = Radar sounding evidence for buried glaciers in the southern mid-latitudes of Mars \| url = \| journal = Science \| volume = 322 \| issue = \| pages = 1235–1238 \| doi=10.1126/science.1164246 \| pmid=19023078\|</ref> <ref name="MorganetalDeuteronilus">\| last1 = Morgan \| first1 = G.A. \| last2 = Head \| first2 = J.W. \| last3 = Marchant \| first3 = D.R. \| year = 2009 \| title = Lineated valley fill (LVF) and lobate debris aprons (LDA) in the Deuteronilus Mensae northern dichotomy boundary region, Mars: Constraints on the extent, age and episodicity of Amazonian glacial events \| url = \| journal = Icarus \| volume = 202 \| issue = \| pages = 22–38 \| doi=10.1016/j.icarus.2009.02.017 \|</ref > <ref name="Plautetal">cite journal \| last1 = Plaut \| first1 = J.J. \| last2 = Safaeinili \| first2 = A. \| last3 = Holt \| first3 = J.W. \| last4 = Phillips \| first4 = R.J. \| last5 = Head \| first5 = J.W. \| last6 = Sue \| first6 = R. \| last7 = Putzig \| first7 = A. \| year = 2009 \| title = Frigeri Radar evidence for ice in lobate debris aprons in the mid-northern latitudes of Mars \| doi = 10.1029/2008gl036379 \| journal = Geophys. Res. Lett. \| volume = 36 \| issue = \| page = L02203 \| </ref> <ref name="Bakeretal2010">cite journal \| last1 = Baker \| first1 = D.M.H. \| last2 = Head \| first2 = J.W. \| last3 = Marchant \| first3 = D.R. \| year = 2010 \| title = Flow patterns of lobate debris aprons and lineated valley fill north of Ismeniae Fossae, Mars: Evidence for extensive mid-latitude glaciation in the Late Amazonian \| url = \| journal = Icarus \| volume = 207 \| issue = \| pages = 186–209 \| doi=10.1016/j.icarus.2009.11.017 \| </ref> <ref name="ArfstromHartmann">cite journal \| last1 = Arfstrom \| first1 = J. \| year = 2005 \| title = Terrestrial analogs and interrelationships \| url = \| journal = Icarus \| volume = 174 \| issue = \| pages = 321–335 \| doi=10.1016/j.icarus.2004.05.026 \| bibcode=2005Icar..174..321A</ref> On Mars these glaciers are covered with rock and dust debris a few meters to a few tens of meters thick.<ref> Baker, D. and L. Carter. 2019. Probing supraglacial debris on Mars 1: Sources, thickness, and stratigraphy. Icarus. Volume 319. Pages 745-769 </ref> Although Mars today seems too dry for any glaciers, this covering material has protected the underlying ice. <ref name="WilliamsSnowpack">cite journal \| last1 = Williams \| first1 = K. E. \| display-authors = 1 \| last2 = et al \| year = 2008 \| title = Stability of mid-latitude snowpacks on Mars \| url = \| journal = Icarus \| volume = 196 \| issue = 2\| pages = 565–577 \| doi=10.1016/j.icarus.2008.03.017 \|</ref> One would think that under today’s conditions any exposed ice would undergo [[sublimation]] and disappear into the thin Martian atmosphere. That is, it would go directly from a solid to a gas. But, the isulating effect of surface material prevents loss of ice.<ref name="Plautetal" /> <ref name="WilliamsSnowpack" /> <ref name="Head, J. 2005">cite journal \| doi = 10.1038/nature03359 \| last1 = Head \| first1 = J. \| date = 2005 \| last2 = Neukum \| first2 = G. \| last3 = Jaumann \| first3 = R. \| last4 = Hiesinger \| first4 = H. \| last5 = Hauber \| first5 = E. \| last6 = Carr \| first6 = M. \| last7 = Masson \| first7 = P. \| last8 = Foing \| first8 = B. \| last9 = Hoffmann \| first9 = H. \| last10 = Kreslavsky \| first10 = M. \| last11 = Werner \| first11 = S. \| last12 = Milkovich \| first12 = S. \| last13 = Van Gasselt \| first13 = S. \| last14 = Co-Investigator Team \| first14 = The Hrsc \| title = Tropical to mid-latitude snow and ice accumulation, flow and glaciation on Mars \| url = \| journal=Nature \| volume = 434 \| issue = 7031\| pages = 346–350 \| pmid=15772652\|</ref> <ref> Head, J., et al. 2009. Northern mid-latitude glaciation in the Late Amazonian period of Mars: Criteria for the recognition of debris-covered glacier and valley glacier landsystem deposits. Earth and Planetary Science Letters. Doi:10.1016/j.epsl.2009.06.041</ref>

	==Water for Future Colonists==		==Water for Future Colonists==

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 == External links ==
 *Head, J., et al.  2023.  GEOLOGICAL AND CLIMATE HISTORY OF MARS: IDENTIFICATION OF POTENTIAL WARM AND
 WET CLIMATE ‘FALSE POSITIVES’.  54th Lunar and Planetary Science Conference 2023 (LPI Contrib. No. 2806).  1731.pdf

@@ Line 86: / Line 86: @@
 Moraines are common on Mars. <ref>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. </ref>   It is believed that most glaciers on Mars are “cold based” that is they do not melt.  Remember, under current conditions ice does not melt, rather it changes  directly to a gas in a process called [[sublimation]].  We do not know if any ice melted in the past.  We may understand the situation much better after we study data from the [[InSight Mission]] which landed on Mars at the end of November 2018.  InSight will measure the heat flow.  A combination of high heat flow and pressure from thick ice, may have generated sufficient heat to cause some melting.
-After several unsuccessful attempts, NASA gave up trying to get heat flow measurements because of the nature of the soil.  The drill, called the mole for this spacecraft could not got deep enough.  It kept popping out.  Almost two years of trying different approaches did not work.  The team attempted to push down the mole with the scoop on the end of the lander’s robotic arm to prevent it from rebounding.  They tried to tamp down regolith around the hole.  They filled in the widening hole so the mole could gain more friction, but nothing worked.<ref>https://spacenews.com/nasa-ceases-efforts-to-deploy-mars-insight-heat-flow-probe</ref> <ref>https://www.jpl.nasa.gov/news/nasa-insights-mole-ends-its-journey-on-mars</ref>
+After several unsuccessful attempts, NASA gave up trying to get heat flow measurements because of the nature of the soil.  The drill, called the mole, could not go deep enough.  It kept popping out.  Almost two years of trying different approaches did not work.  The team attempted to push down the mole with the scoop on the end of the lander’s robotic arm to prevent it from rebounding.  They tried to tamp down regolith around the hole.  They filled in the widening hole so the mole could gain more friction, but nothing worked.<ref>https://spacenews.com/nasa-ceases-efforts-to-deploy-mars-insight-heat-flow-probe</ref> <ref>https://www.jpl.nasa.gov/news/nasa-insights-mole-ends-its-journey-on-mars</ref>
 [[File:PIA17358-MarsInSightLander-20140326.jpg|600pxr|Labeled drawing of InSight Lander]]

← Older revision		Revision as of 23:58, 20 December 2023
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	Moraines are common on Mars. <ref>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. </ref> It is believed that most glaciers on Mars are “cold based” that is they do not melt. Remember, under current conditions ice does not melt, rather it changes directly to a gas in a process called [[sublimation]]. We do not know if any ice melted in the past. We may understand the situation much better after we study data from the [[InSight Mission]] which landed on Mars at the end of November 2018. InSight will measure the heat flow. A combination of high heat flow and pressure from thick ice, may have generated sufficient heat to cause some melting.		Moraines are common on Mars. <ref>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. </ref> It is believed that most glaciers on Mars are “cold based” that is they do not melt. Remember, under current conditions ice does not melt, rather it changes directly to a gas in a process called [[sublimation]]. We do not know if any ice melted in the past. We may understand the situation much better after we study data from the [[InSight Mission]] which landed on Mars at the end of November 2018. InSight will measure the heat flow. A combination of high heat flow and pressure from thick ice, may have generated sufficient heat to cause some melting.
		+
		+	After several unsuccessful attempts, NASA gave up trying to get heat flow measurements because of the nature of the soil. The drill, called the mole for this spacecraft could not got deep enough. It kept popping out. Almost two years of trying different approaches did not work. The team attempted to push down the mole with the scoop on the end of the lander’s robotic arm to prevent it from rebounding. They tried to tamp down regolith around the hole. They filled in the widening hole so the mole could gain more friction, but nothing worked.<ref>https://spacenews.com/nasa-ceases-efforts-to-deploy-mars-insight-heat-flow-probe</ref> <ref>https://www.jpl.nasa.gov/news/nasa-insights-mole-ends-its-journey-on-mars</ref>

	[[File:PIA17358-MarsInSightLander-20140326.jpg\|600pxr\|Labeled drawing of InSight Lander]]		[[File:PIA17358-MarsInSightLander-20140326.jpg\|600pxr\|Labeled drawing of InSight Lander]]