Sinus Sabaeus quadrangle - Revision history

Suitupshowup at 14:10, 24 January 2025

2025-01-24T14:10:46Z

← Older revision		Revision as of 15:10, 24 January 2025
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	\|[[Mars Atlas\|Atlas]]		\|[[Mars Atlas\|Atlas]]
	\|}		\|}

			In this article, some of the best pictures from a number of spacecraft will show what the landscape looks like in this region. The origins and significance of all features will be explained as they are currently understood.


	<gallery widths="400" heights="300">		<gallery widths="400" heights="300">
	File:USGS-Mars-MC-20-SinusSabaeusRegion-mola.png		File:USGS-Mars-MC-20-SinusSabaeusRegion-mola.png

Suitupshowup: added image

2024-12-22T17:35:53Z

added image

← Older revision		Revision as of 18:35, 22 December 2024
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	File:PIA00180-MC-20-SinusSabeusRegion-19980605.jpg		File:PIA00180-MC-20-SinusSabeusRegion-19980605.jpg
	</gallery>		</gallery>

			[[File:Collage sinussabaeus 01.jpg\|Features of Features of Sinus Sabaeus quadrangle, as seen by HiRISE under under HiWish program\|600pxr\| Features of Sinus Sabaeus quadrangle]]

			Scenes of the Sinus Sabaeus quadrangle


	The Sinus Sabaeus quadrangle contains a few very interesting craters. One contains a strange white rock in the center. Another crater, Schiaparelli, is a large, easily located crater on the equator. There are several neat exposures of layers in this quadrangle. Most of the region contains heavily cratered highlands.		The Sinus Sabaeus quadrangle contains a few very interesting craters. One contains a strange white rock in the center. Another crater, Schiaparelli, is a large, easily located crater on the equator. There are several neat exposures of layers in this quadrangle. Most of the region contains heavily cratered highlands.

Suitupshowup: /* Other craters */ added images

2024-10-09T13:55:11Z

Other craters: added images

← Older revision		Revision as of 14:55, 9 October 2024
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	[[File:Wikibakhuysenchannels.jpg \|600pxr\|Channels on south rim of Bakhuysen Crater, as seen by CTX camera (on Mars Reconnaissance Orbiter). Note: this is an enlargement of the previous image of Bakhuysen Crater.]]		[[File:Wikibakhuysenchannels.jpg \|600pxr\|Channels on south rim of Bakhuysen Crater, as seen by CTX camera (on Mars Reconnaissance Orbiter). Note: this is an enlargement of the previous image of Bakhuysen Crater.]]
	Channels on south rim of Bakhuysen Crater, as seen by CTX camera (on Mars Reconnaissance Orbiter). Note: this is an enlargement of the previous image of Bakhuysen Crater.		Channels on south rim of Bakhuysen Crater, as seen by CTX camera (on Mars Reconnaissance Orbiter). Note: this is an enlargement of the previous image of Bakhuysen Crater.

			<gallery class="center" widths="380px" heights="360px">
			File:75431 1665ejecta2.jpg\|Crater with colorful ejecta, as seen by HiRISE under the HiWish program The ejecta represents samples of material from underground. Craters allow us to study underlying material.

			File:75431 1665ejecta3.jpg\|Crater with colorful ejecta, as seen by HiRISE The ejecta represents samples of material from underground. Craters allow us to study underlying material.
			</gallery>

	== White rock in Pollack crater ==		== White rock in Pollack crater ==

Suitupshowup: /* Dunes */ added images

2024-06-12T15:00:40Z

Dunes: added images

← Older revision		Revision as of 16:00, 12 June 2024
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	== Dunes ==		== Dunes ==

			Dunes of various shapes are common on Mars, especially on the floors of craters. Sand gets into craters and then the winds are not strong enough to get it over the rim. Although Mars can have wind with a high velocity, the wind lacks power since the air is so thin--only 1 % of the Earth.

	<gallery class="center" widths="380px" heights="360px">		<gallery class="center" widths="380px" heights="360px">

	File:ESP 054976 1685dunes.jpg\|Dunes, as seen with HiRISE under the HiWish program.		File:ESP 054976 1685dunes.jpg\|Dunes, as seen with HiRISE under the HiWish program.
			</gallery>

			Dunes of various shapes are common on Mars, especially on the floors of craters. Sand gets into craters and then the winds are not strong enough to get it over the rim. Although Mars can have wind with a high velocity, the wind lacks power since the air is so thin--only 1 % of the Earth. '

			<gallery class="center" widths="380px" heights="360px">
			File:ESP 082974 1685ridge and star shaped dunes 01.jpg\|Wide view of crater showing ridges and varioujs shaped sand dunes on floor.

			File:ESP 082974 1685ridge and star shaped dunes 02.jpg\|Close view of various shaped dunes Picture is about 1 km across.
			File:ESP 082974 1685 star shaped dunes 03.jpg\|Close view of various shaped dunes Picture is about 1 km across. Some dunes would be called star dunes.
			File:ESP 082974 1685ridge and star shaped dunes 04.jpg\|Close view of various shaped dunes Picture is about 1 km across.
			File:ESP 082974 1685 star shaped dunes 03.jpg\|Close view of various shaped dunes Picture is about 1 km across. Some dunes would be called star dunes.
			File:ESP 082974 1685star shaped dunes 05.jpg\|Close view of various shaped dunes Picture is about 1 km across.
	</gallery>		</gallery>

Suitupshowup at 23:09, 16 November 2023

2023-11-16T23:09:51Z

← Older revision		Revision as of 00:09, 17 November 2023
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	File:Boulders and cap rock of a mesa.jpg\|Close view of mesa, as seen by HiRISE House-sized boulders are present in abundance. This image was named HiRISE picture of the day for November 14, 2023.		File:Boulders and cap rock of a mesa.jpg\|Close view of mesa, as seen by HiRISE House-sized boulders are present in abundance. This image was named HiRISE picture of the day for November 14, 2023.
	File:Cap rock and layers of a mesa.jpg\|Close view of cap rock, as seen by HiRISE The cap rock overhangs some layers. The cap rock was more resistant to erosion, so it formed an overhang.		File:Cap rock and layers of a mesa.jpg\|Close view of cap rock, as seen by HiRISE The cap rock overhangs some layers. The cap rock was more resistant to erosion, so it formed an overhang.
	</~~galley~~>		</gallery>

	==See also==		==See also==

Suitupshowup: /* Other scenes in Sinus Sabaeus quadrangle */ added images

2023-11-16T23:09:10Z

Other scenes in Sinus Sabaeus quadrangle: added images

← Older revision		Revision as of 00:09, 17 November 2023
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	==Other scenes in Sinus Sabaeus quadrangle==		==Other scenes in Sinus Sabaeus quadrangle==

			<gallery class="center" widths="380px" heights="360px">

	File:ESP 080784 2035mesaboulders 01.jpg\|Wide view of mesas, as seen by HiRISE under HiWish program		File:ESP 080784 2035mesaboulders 01.jpg\|Wide view of mesas, as seen by HiRISE under HiWish program
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	File:Boulders and cap rock of a mesa.jpg\|Close view of mesa, as seen by HiRISE House-sized boulders are present in abundance. This image was named HiRISE picture of the day for November 14, 2023.		File:Boulders and cap rock of a mesa.jpg\|Close view of mesa, as seen by HiRISE House-sized boulders are present in abundance. This image was named HiRISE picture of the day for November 14, 2023.
	File:Cap rock and layers of a mesa.jpg\|Close view of cap rock, as seen by HiRISE The cap rock overhangs some layers. The cap rock was more resistant to erosion, so it formed an overhang.		File:Cap rock and layers of a mesa.jpg\|Close view of cap rock, as seen by HiRISE The cap rock overhangs some layers. The cap rock was more resistant to erosion, so it formed an overhang.
			</galley>


	==See also==		==See also==

Suitupshowup: /* See also */

2023-11-16T23:08:19Z

Suitupandshowup: /* Channels in Sinus Sabaeus quadrangle */ added new info and ref

2021-04-06T01:31:01Z

Channels in Sinus Sabaeus quadrangle: added new info and ref

← Older revision		Revision as of 02:31, 6 April 2021
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	There is enormous evidence that water once flowed in river valleys on Mars.<ref>Baker, V., et al. 2015. Fluvial geomorphology on Earth-like planetary surfaces: a review. Geomorphology. 245, 149–182.</ref> <ref>Carr, M. 1996. in Water on Mars. Oxford Univ. Press.</ref> Images of curved channels have been seen in images from Mars spacecraft dating back to the early seventies with the [[Mariner 9]] orbiter.<ref>Baker, V. 1982. The Channels of Mars. Univ. of Tex. Press, Austin, TX</ref> <ref>Baker, V., R. Strom, R., V. Gulick, J. Kargel, G. Komatsu, V. Kale. 1991. Ancient oceans, ice sheets and the hydrological cycle on Mars. Nature 352, 589–594.</ref> <ref>Carr, M. 1979. Formation of Martian flood features by release of water from confined aquifers. J. Geophys. Res. 84, 2995–300.</ref> <ref>Komar, P. 1979. Comparisons of the hydraulics of water flows in Martian outflow channels with flows of similar scale on Earth. Icarus 37, 156–181.</ref> As Mars has been studied in the decades since Mariner 9, more and more river-like forms have been seen. Indeed, a study published in June 2017, calculated that the volume of water needed to carve all the channels on Mars was even larger than the proposed ocean that the planet may have had. Water was probably recycled many times from the ocean to rainfall around Mars.<ref>http://spaceref.com/mars/how-much-water-was-needed-to-carve-valleys-on-mars.html</ref> <ref>Luo, W., et al. 2017. New Martian valley network volume estimate consistent with ancient ocean and warm and wet climate. Nature Communications 8. Article number: 15766 (2017). doi:10.1038/ncomms15766</ref>		There is enormous evidence that water once flowed in river valleys on Mars.<ref>Baker, V., et al. 2015. Fluvial geomorphology on Earth-like planetary surfaces: a review. Geomorphology. 245, 149–182.</ref> <ref>Carr, M. 1996. in Water on Mars. Oxford Univ. Press.</ref> Images of curved channels have been seen in images from Mars spacecraft dating back to the early seventies with the [[Mariner 9]] orbiter.<ref>Baker, V. 1982. The Channels of Mars. Univ. of Tex. Press, Austin, TX</ref> <ref>Baker, V., R. Strom, R., V. Gulick, J. Kargel, G. Komatsu, V. Kale. 1991. Ancient oceans, ice sheets and the hydrological cycle on Mars. Nature 352, 589–594.</ref> <ref>Carr, M. 1979. Formation of Martian flood features by release of water from confined aquifers. J. Geophys. Res. 84, 2995–300.</ref> <ref>Komar, P. 1979. Comparisons of the hydraulics of water flows in Martian outflow channels with flows of similar scale on Earth. Icarus 37, 156–181.</ref> As Mars has been studied in the decades since Mariner 9, more and more river-like forms have been seen. Indeed, a study published in June 2017, calculated that the volume of water needed to carve all the channels on Mars was even larger than the proposed ocean that the planet may have had. Water was probably recycled many times from the ocean to rainfall around Mars.<ref>http://spaceref.com/mars/how-much-water-was-needed-to-carve-valleys-on-mars.html</ref> <ref>Luo, W., et al. 2017. New Martian valley network volume estimate consistent with ancient ocean and warm and wet climate. Nature Communications 8. Article number: 15766 (2017). doi:10.1038/ncomms15766</ref>

			Many crater contained lakes. Some craters in the Sinus Sabaeus quadrangle are believed to have formed from the melting of glaciers on their rims. Inverted streams are found on the floors of some craters. Water from glaciers carried debris in channels and consequently that debris was left behind after the surrounding ground eroded.<ref>Boatwright, B., et al. 2021. INVERTED FLUVIAL CHANNELS IN TERRA SABAEA, MARS: GEOMORPHIC EVIDENCE FOR
			PROGLACIAL LAKES AND WIDESPREAD HIGHLANDS GLACIATION IN THE LATE NOACHIAN. 52nd Lunar and Planetary Science Conference 2021 (LPI Contrib. No. 2548). 1641.pdf</ref> <ref>https://www.brown.edu/news/2021-03-30/crater-lake?fbclid=IwAR0QGkqpUazmc4qCTgDVzGdYuprxiuqQK0hGkfraGR0hg8z63DmaT_bO4FQ</ref>


	<gallery class="center" widths="190px" heights="180px" >		<gallery class="center" widths="190px" heights="180px" >

Michel Lamontagne at 16:02, 21 April 2020

2020-04-21T16:02:06Z

← Older revision		Revision as of 17:02, 21 April 2020
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			{{Mars atlas}}
	{\| class="wikitable sortable"		{\| class="wikitable sortable"
	\|MC-20		\|MC-20

Suitupandshowup at 17:13, 26 March 2020

2020-03-26T17:13:26Z

@@ Line 142: / Line 142: @@
 File:ESP 054976 1685dunes.jpg|Dunes, as seen with HiRISE under the HiWish program.
 </gallery>
 ==See also==

← Older revision		Revision as of 18:13, 26 March 2020
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	</gallery>		</gallery>

	The Sinus Sabaeus quadrangle contains a few very interesting craters. One contains a strange white rock in the center. Another crater, Schiaparelli, is a large, easily located crater on the equator. There are several neat exposures of layers in ~~the region~~. Most of the region contains heavily cratered highlands.		The Sinus Sabaeus quadrangle contains a few very interesting craters. One contains a strange white rock in the center. Another crater, Schiaparelli, is a large, easily located crater on the equator. There are several neat exposures of layers in this quadrangle. Most of the region contains heavily cratered highlands.
	In this article, some of the best pictures from a number of spacecraft will show what the landscape looks like in this region. The origins and significance of all features will be explained as they are currently understood.		In this article, some of the best pictures from a number of spacecraft will show what the landscape looks like in this region. The origins and significance of all features will be explained as they are currently understood.
	The Sinus Sabaeus quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS). It is also referred to as MC-20 (Mars Chart-20).<ref>Davies, M.E.; Batson, R.M.; Wu, S.S.C. “Geodesy and Cartography” in Kieffer, H.H.; Jakosky, B.M.; Snyder, C.W.; Matthews, M.S., Eds. ''Mars.'' University of Arizona Press: Tucson, 1992.</ref>		The Sinus Sabaeus quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS). It is also referred to as MC-20 (Mars Chart-20).<ref>Davies, M.E.; Batson, R.M.; Wu, S.S.C. “Geodesy and Cartography” in Kieffer, H.H.; Jakosky, B.M.; Snyder, C.W.; Matthews, M.S., Eds. ''Mars.'' University of Arizona Press: Tucson, 1992.</ref>
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	Image:Bouguercraterhirise.jpg\|Close up of layers in eroded deposits on the floor of Bouguer Crater, as seen by HiRISE. This image is in a different part of the crater than the previous image.		Image:Bouguercraterhirise.jpg\|Close up of layers in eroded deposits on the floor of Bouguer Crater, as seen by HiRISE. This image is in a different part of the crater than the previous image.

	Image:Layers in Monument Valley.jpg\|Layers in Monument Valley. These are accepted as being formed, at least in part, by water ~~deposition~~. Since Mars contains similar layers, water remains as a major cause of layering ~~on Mars~~.		Image:Layers in Monument Valley.jpg\|Layers in Monument Valley. These are accepted as being formed, at least in part, with the aid of water. Since Mars contains similar layers, water remains as a major cause of layering.

	Image:26876whitelayers.jpg\|White layers that may be related to the white material in Pollack Crater, as seen by HiRISE under [[HiWish program]].		Image:26876whitelayers.jpg\|White layers that may be related to the white material in Pollack Crater, as seen by HiRISE under [[HiWish program]].
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	Layers in crater found within the Schiaparelli Crater basin as seen by Mars Global Surveyor		Layers in crater found within the Schiaparelli Crater basin as seen by Mars Global Surveyor

	Schiaparelli is an impact crater located near Mars's equator. It is 461 km in diameter and located at latitude 3° south and longitude 344° W. Some places within Schiaparelli show many layers that may have formed by the wind, volcanoes, or deposition under water. Some are quite beautiful as shown in the pictures below. People often seek to travel to our national parks like the Grand Canyon to see layers like the ones in Schiaparelli.		Schiaparelli is an impact crater located near Mars's equator. It is 461 km in diameter and located at latitude 3° south and longitude 344° W. Some places within Schiaparelli show many layers that may have formed by the wind, volcanoes, or deposition under water. Some are quite beautiful as shown in the pictures above and below. People often seek to travel to our national parks like the Grand Canyon to see layers like the ones in Schiaparelli.

	<gallery class="center" widths="380px" heights="360px">		<gallery class="center" widths="380px" heights="360px">
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	Image:ESP 028511rings.jpg\|Circular structures on floor of Schiaparelli Crater~~, as seen by HiRISE under HiWish program~~		Image:ESP 028511rings.jpg\|Circular structures on floor of Schiaparelli Crater


	46814 1785layeredmound.jpg\|Layered mound in Schiaparelli Crater~~, as seen by HiRISE under HiWish program~~		46814 1785layeredmound.jpg\|Layered mound in Schiaparelli Crater

	File: 46814 1785layeredmound2.jpg\|Layers in Schiaparelli Crater~~, as seen by HiRISE under HiWish program~~		File: 46814 1785layeredmound2.jpg\|Layers in Schiaparelli Crater

	46814 1785layeresleft.jpg\|Layers in Schiaparelli Crater~~, as seen by HiRISE under HiWish program~~		46814 1785layeresleft.jpg\|Layers in Schiaparelli Crater


	46814 1785layerscloseleftbottom.jpg\|Close view of layers in Schiaparelli Crater, as seen by HiRISE under HiWish ~~program~~ Dark sand is visible on some layers.		46814 1785layerscloseleftbottom.jpg\|Close view of layers in Schiaparelli Crater, as seen by HiRISE under[[ HiWish ]] Dark sand is visible on some layers.
	ESP 046814 1785layersclosecolor.jpg\|Close, color view of layers in Schiaparelli Crater~~, as seen by HiRISE under HiWish program~~ Dark sand is visible on some layers.
			ESP 046814 1785layersclosecolor.jpg\|Close, color view of layers in Schiaparelli Crater Dark sand is visible on some layers.

	</gallery>		</gallery>
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	== Other Craters ==		== Other Craters ==

	When a comet or asteroid collides at a high rate of speed with the surface of Mars, it creates a primary impact crater. The primary impact may also eject significant numbers of rocks which eventually fall back to make secondary craters.<ref>http://hirise.lpl.arizona.edu/science_themes/impact.php</ref> Secondary craters may be arranged in clusters. ~~All of the craters in the cluster would appear to be equally eroded; since they have the same age.~~ If ~~these~~ secondary craters formed from a single, large, nearby impact, then they would have formed at roughly the same instant in time~~. The~~ image ~~below~~ of Denning Crater ~~shows a cluster of secondary craters~~.		When a comet or asteroid collides at a high rate of speed with the surface of Mars, it creates a primary impact crater. The primary impact may also eject significant numbers of rocks which eventually fall back to make secondary craters.<ref>http://hirise.lpl.arizona.edu/science_themes/impact.php</ref> Secondary craters may be arranged in clusters. If secondary craters formed from a single, large, nearby impact, then they would have formed at roughly the same instant in time and be of the same age--which is how they appear below in the image of Denning Crater.

	<gallery class="center" widths="380px" heights="360px">		<gallery class="center" widths="380px" heights="360px">
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	== White rock in Pollack crater ==		== White rock in Pollack crater ==

	Within ~~the region~~ is Pollack crater, which has light-toned rock deposits. Mars has an old surface compared to Earth. While much of Earth's land surface is just a few hundred million years old, large areas of Mars are billions of years old. Some surface areas have been formed, eroded away, and then covered over with new layers of rocks. The [[Mariner 9]] spacecraft in the 1970s photographed a feature that was called "White Rock." Newer images revealed that the rock is not really white, but that the area close by is so dark that the white rock looks really white.<ref> Grotzinger, J. and R. Milliken (eds.) 2012. Sedimentary Geology of Mars. SEPM</ref> It was thought that this feature could have been a salt deposit, but information from the instruments on [[Mars Global Surveyor]] demonstrated rather that it was probably volcanic ash or dust. Today, it is believed that White Rock represents an old rock layer that once filled the whole crater that it's in, but today the whitish rock has since been mostly eroded away. The picture below shows white rock with a spot of the same rock some distance from the main deposit, so it is thought that the white material once covered a far larger area.<ref>http://space.com/scienceastronomy/solarsystem/mars_daily_020419.html</ref>		Within this quadrangle is Pollack crater, which has light-toned rock deposits. Mars has an old surface compared to Earth. While much of Earth's land surface is just a few hundred million years old, large areas of Mars are billions of years old. Some surface areas have been formed, eroded away, and then covered over with new layers of rocks. The [[Mariner 9]] spacecraft in the 1970s photographed a feature that was called "White Rock." Newer images revealed that the rock is not really white, but that the area close by is so dark that the white rock looks really white.<ref> Grotzinger, J. and R. Milliken (eds.) 2012. Sedimentary Geology of Mars. SEPM</ref> It was thought that this feature could have been a salt deposit, but information from the instruments on [[Mars Global Surveyor]] demonstrated rather that it was probably volcanic ash or dust. Today, it is believed that White Rock represents an old rock layer that once filled the whole crater that it's in, but today the whitish rock has since been mostly eroded away. The picture below shows white rock with a spot of the same rock some distance from the main deposit, so it is thought that the white material once covered a far larger area.<ref>http://space.com/scienceastronomy/solarsystem/mars_daily_020419.html</ref>

	<gallery class="center" widths="380px" heights="360px">		<gallery class="center" widths="380px" heights="360px">
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	==Channels in Sinus Sabaeus quadrangle==		==Channels in Sinus Sabaeus quadrangle==

	There is enormous evidence that water once flowed in river valleys on Mars.<ref>Baker, V., et al. 2015. Fluvial geomorphology on Earth-like planetary surfaces: a review. Geomorphology. 245, 149–182.</ref> <ref>Carr, M. 1996. in Water on Mars. Oxford Univ. Press.</ref> Images of curved channels have been seen in images from Mars spacecraft dating back to the early seventies with the [[Mariner 9]] orbiter.<ref>Baker, V. 1982. The Channels of Mars. Univ. of Tex. Press, Austin, TX</ref> <ref>Baker, V., R. Strom, R., V. Gulick, J. Kargel, G. Komatsu, V. Kale. 1991. Ancient oceans, ice sheets and the hydrological cycle on Mars. Nature 352, 589–594.</ref> <ref>Carr, M. 1979. Formation of Martian flood features by release of water from confined aquifers. J. Geophys. Res. 84, 2995–300.</ref> <ref>Komar, P. 1979. Comparisons of the hydraulics of water flows in Martian outflow channels with flows of similar scale on Earth. Icarus 37, 156–181.</ref> Indeed, a study published in June 2017, calculated that the volume of water needed to carve all the channels on Mars was even larger than the proposed ocean that the planet may have had. Water was probably recycled many times from the ocean to rainfall around Mars.<ref>http://spaceref.com/mars/how-much-water-was-needed-to-carve-valleys-on-mars.html</ref> <ref>Luo, W., et al. 2017. New Martian valley network volume estimate consistent with ancient ocean and warm and wet climate. Nature Communications 8. Article number: 15766 (2017). doi:10.1038/ncomms15766</ref>		There is enormous evidence that water once flowed in river valleys on Mars.<ref>Baker, V., et al. 2015. Fluvial geomorphology on Earth-like planetary surfaces: a review. Geomorphology. 245, 149–182.</ref> <ref>Carr, M. 1996. in Water on Mars. Oxford Univ. Press.</ref> Images of curved channels have been seen in images from Mars spacecraft dating back to the early seventies with the [[Mariner 9]] orbiter.<ref>Baker, V. 1982. The Channels of Mars. Univ. of Tex. Press, Austin, TX</ref> <ref>Baker, V., R. Strom, R., V. Gulick, J. Kargel, G. Komatsu, V. Kale. 1991. Ancient oceans, ice sheets and the hydrological cycle on Mars. Nature 352, 589–594.</ref> <ref>Carr, M. 1979. Formation of Martian flood features by release of water from confined aquifers. J. Geophys. Res. 84, 2995–300.</ref> <ref>Komar, P. 1979. Comparisons of the hydraulics of water flows in Martian outflow channels with flows of similar scale on Earth. Icarus 37, 156–181.</ref> As Mars has been studied in the decades since Mariner 9, more and more river-like forms have been seen. Indeed, a study published in June 2017, calculated that the volume of water needed to carve all the channels on Mars was even larger than the proposed ocean that the planet may have had. Water was probably recycled many times from the ocean to rainfall around Mars.<ref>http://spaceref.com/mars/how-much-water-was-needed-to-carve-valleys-on-mars.html</ref> <ref>Luo, W., et al. 2017. New Martian valley network volume estimate consistent with ancient ocean and warm and wet climate. Nature Communications 8. Article number: 15766 (2017). doi:10.1038/ncomms15766</ref>

	<gallery class="center" widths="190px" heights="180px" >		<gallery class="center" widths="190px" heights="180px" >

	ESP 041974 1740channel.jpg\|Winding channel~~, as seen by HiRISE under HiWish program~~		ESP 041974 1740channel.jpg\|Winding channel
	ESP 045813 1510channels.jpg\|Channels~~, as seen by HiRISE under HiWish program~~		ESP 045813 1510channels.jpg\|Channels
	ESP 051192 1555channel.jpg\|Channels, as seen by HiRISE under HiWish program		ESP 051192 1555channel.jpg\|Channels, as seen by HiRISE under [[HiWish program]]


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	<gallery class="center" widths="380px" heights="360px">		<gallery class="center" widths="380px" heights="360px">

	File:ESP 057415 1740ridge.jpg\|This straight ridge may be a dike that has been exposed by erosion. It was initially formed by magma moving under the surface along weak spots. ~~The picture was taken with HiRISE under the HiWish program.~~		File:ESP 057415 1740ridge.jpg\|This straight ridge may be a dike that has been exposed by erosion. It was initially formed by magma moving under the surface along weak spots.

	ESP 047368 1665ridge.jpg\|~~This~~ long, straight ridge may be a dike that has been exposed by erosion. It was initially formed by magma moving under the surface. The picture was taken with HiRISE under the HiWish program.		ESP 047368 1665ridge.jpg\|Another long, straight ridge may be a dike that has been exposed by erosion. It was initially formed by magma moving under the surface. The picture was taken with HiRISE under the HiWish program.
	</gallery>		</gallery>

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	<gallery class="center" widths="380px" heights="360px">		<gallery class="center" widths="380px" heights="360px">



	File:ESP 054976 1685dunes.jpg\|Dunes, as seen with HiRISE under the HiWish program.		File:ESP 054976 1685dunes.jpg\|Dunes, as seen with HiRISE under the HiWish program.