http://marspedia.org/index.php?title=Mare_Boreum_quadrangle&feed=atom&action=historyMare Boreum quadrangle - Revision history2024-03-29T13:50:11ZRevision history for this page on the wikiMediaWiki 1.34.2http://marspedia.org/index.php?title=Mare_Boreum_quadrangle&diff=140909&oldid=prevMichel Lamontagne at 12:51, 14 March 20242024-03-14T12:51:48Z<p></p>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The quadrangle covers all of the Martian surface north of latitude 65°. It includes the north polar ice cap, which has a swirl pattern and is roughly 1100 km across. [[Mariner 9]] in 1972 discovered a belt of sand dunes that ring the polar ice deposits. The belt is 500 km across in some places and may be the largest dune field in the solar system.<ref>Hartmann, W. 2003. A Traveler's Guide to Mars. Workman Publishing. NY NY.</ref> The ice cap is surrounded by the vast plains of Planum Boreum and Vastitas Borealis. Close to the pole, there is a large valley, Chasma Boreale, that may have been formed from water melting from the ice cap.<ref>Clifford, S. 1987. Polar basal melting on Mars. J. Geophys. Res. 92: 9135-9152.</ref> An alternative view is that it was made by winds coming off the cold pole.<ref>Howard, A. 2000. The role of eolian processes in forming surface features of the martian polar layered deposits. Icarus. 144: 267-288.</ref> <ref>Edgett, K. et al. 2003. Mars landscape evolution: influence of stratigraphy on geomorphology of the north polar region. Geomorphology. 52: 289-298.</ref> Another prominent feature is a smooth rise, formerly called Olympia Planitia. In the summer, a dark collar around the residual cap becomes visible; it is mostly caused by dunes.<ref>Michael H. Carr|title=The surface of Mars|url=https://books.google.com/books?id=uLHlJ6sjohwC|accessdate=21 March 2011|year=2006|publisher=Cambridge University Press|isbn=978-0-521-87201-0</ref> The quadrangle includes some very large craters that stand out in the north because the area is smooth. In other words, they really stand out. These large craters are Lomonosov, and Korolev. Although smaller, the crater Stokes is also prominent.</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The quadrangle covers all of the Martian surface north of latitude 65°. It includes the north polar ice cap, which has a swirl pattern and is roughly 1100 km across. [[Mariner 9]] in 1972 discovered a belt of sand dunes that ring the polar ice deposits. The belt is 500 km across in some places and may be the largest dune field in the solar system.<ref>Hartmann, W. 2003. A Traveler's Guide to Mars. Workman Publishing. NY NY.</ref> The ice cap is surrounded by the vast plains of Planum Boreum and Vastitas Borealis. Close to the pole, there is a large valley, Chasma Boreale, that may have been formed from water melting from the ice cap.<ref>Clifford, S. 1987. Polar basal melting on Mars. J. Geophys. Res. 92: 9135-9152.</ref> An alternative view is that it was made by winds coming off the cold pole.<ref>Howard, A. 2000. The role of eolian processes in forming surface features of the martian polar layered deposits. Icarus. 144: 267-288.</ref> <ref>Edgett, K. et al. 2003. Mars landscape evolution: influence of stratigraphy on geomorphology of the north polar region. Geomorphology. 52: 289-298.</ref> Another prominent feature is a smooth rise, formerly called Olympia Planitia. In the summer, a dark collar around the residual cap becomes visible; it is mostly caused by dunes.<ref>Michael H. Carr|title=The surface of Mars|url=https://books.google.com/books?id=uLHlJ6sjohwC|accessdate=21 March 2011|year=2006|publisher=Cambridge University Press|isbn=978-0-521-87201-0</ref> The quadrangle includes some very large craters that stand out in the north because the area is smooth. In other words, they really stand out. These large craters are Lomonosov, and Korolev. Although smaller, the crater Stokes is also prominent.</div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">==US Geological survey map==</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">The US Geological survey map of the North pole offers a wealth of data about the geology of Mars and shows the extend of the polar ice.</ins></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>https://pubs.usgs.gov/sim/3177/sim3177_sheet.pdf</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>https://pubs.usgs.gov/sim/3177/sim3177_sheet.pdf</div></td></tr>
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</table>Michel Lamontagnehttp://marspedia.org/index.php?title=Mare_Boreum_quadrangle&diff=140908&oldid=prevMichel Lamontagne at 12:50, 14 March 20242024-03-14T12:50:16Z<p></p>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The quadrangle covers all of the Martian surface north of latitude 65°. It includes the north polar ice cap, which has a swirl pattern and is roughly 1100 km across. [[Mariner 9]] in 1972 discovered a belt of sand dunes that ring the polar ice deposits. The belt is 500 km across in some places and may be the largest dune field in the solar system.<ref>Hartmann, W. 2003. A Traveler's Guide to Mars. Workman Publishing. NY NY.</ref> The ice cap is surrounded by the vast plains of Planum Boreum and Vastitas Borealis. Close to the pole, there is a large valley, Chasma Boreale, that may have been formed from water melting from the ice cap.<ref>Clifford, S. 1987. Polar basal melting on Mars. J. Geophys. Res. 92: 9135-9152.</ref> An alternative view is that it was made by winds coming off the cold pole.<ref>Howard, A. 2000. The role of eolian processes in forming surface features of the martian polar layered deposits. Icarus. 144: 267-288.</ref> <ref>Edgett, K. et al. 2003. Mars landscape evolution: influence of stratigraphy on geomorphology of the north polar region. Geomorphology. 52: 289-298.</ref> Another prominent feature is a smooth rise, formerly called Olympia Planitia. In the summer, a dark collar around the residual cap becomes visible; it is mostly caused by dunes.<ref>Michael H. Carr|title=The surface of Mars|url=https://books.google.com/books?id=uLHlJ6sjohwC|accessdate=21 March 2011|year=2006|publisher=Cambridge University Press|isbn=978-0-521-87201-0</ref> The quadrangle includes some very large craters that stand out in the north because the area is smooth. In other words, they really stand out. These large craters are Lomonosov, and Korolev. Although smaller, the crater Stokes is also prominent.</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The quadrangle covers all of the Martian surface north of latitude 65°. It includes the north polar ice cap, which has a swirl pattern and is roughly 1100 km across. [[Mariner 9]] in 1972 discovered a belt of sand dunes that ring the polar ice deposits. The belt is 500 km across in some places and may be the largest dune field in the solar system.<ref>Hartmann, W. 2003. A Traveler's Guide to Mars. Workman Publishing. NY NY.</ref> The ice cap is surrounded by the vast plains of Planum Boreum and Vastitas Borealis. Close to the pole, there is a large valley, Chasma Boreale, that may have been formed from water melting from the ice cap.<ref>Clifford, S. 1987. Polar basal melting on Mars. J. Geophys. Res. 92: 9135-9152.</ref> An alternative view is that it was made by winds coming off the cold pole.<ref>Howard, A. 2000. The role of eolian processes in forming surface features of the martian polar layered deposits. Icarus. 144: 267-288.</ref> <ref>Edgett, K. et al. 2003. Mars landscape evolution: influence of stratigraphy on geomorphology of the north polar region. Geomorphology. 52: 289-298.</ref> Another prominent feature is a smooth rise, formerly called Olympia Planitia. In the summer, a dark collar around the residual cap becomes visible; it is mostly caused by dunes.<ref>Michael H. Carr|title=The surface of Mars|url=https://books.google.com/books?id=uLHlJ6sjohwC|accessdate=21 March 2011|year=2006|publisher=Cambridge University Press|isbn=978-0-521-87201-0</ref> The quadrangle includes some very large craters that stand out in the north because the area is smooth. In other words, they really stand out. These large craters are Lomonosov, and Korolev. Although smaller, the crater Stokes is also prominent.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">https://pubs.usgs.gov/sim/3177/sim3177_sheet.pdf</ins></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Ice cap==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Ice cap==</div></td></tr>
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</table>Michel Lamontagnehttp://marspedia.org/index.php?title=Mare_Boreum_quadrangle&diff=140647&oldid=prevSuitupshowup: /* Dunes */2023-12-24T02:17:29Z<p><span dir="auto"><span class="autocomment">Dunes</span></span></p>
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<td colspan="2" style="background-color: #fff; color: #222; text-align: center;">Revision as of 02:17, 24 December 2023</td>
</tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l73" >Line 73:</td>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[[File:ESP 043821 2555dryice.jpg|600pxr|Defrosting dunes and ice in troughs of polygons, as seen by HiRISE under [[HiWish program]]]]</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[[File:ESP 043821 2555dryice.jpg|600pxr|Defrosting dunes and ice in troughs of polygons, as seen by HiRISE under [[HiWish program]]]]</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del class="diffchange diffchange-inline"> </del>Defrosting dunes and ice in troughs of polygons, as seen by HiRISE under [[HiWish program]]</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline"> </ins>Defrosting dunes and ice in troughs of polygons, as seen by HiRISE under [[HiWish program]]</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Sand dunes have been found in many places on Mars. The presence of dunes shows that the planet has an atmosphere with wind, for dunes require wind to pile up the sand. Most dunes on Mars are black because of the weathering of the volcanic rock basalt.<ref>http://hirise.lpl.arizona.edu/ESP_016459_1830</ref> <ref> Michael H. Carr (2006). The surface of Mars. Cambridge University Press. ISBN 978-0-521-87201-0.</ref> Black sand can be found on Earth on Hawaii and on some tropical South Pacific islands.<ref>https://www.desertusa.com/desert-activity/sand-dune-wind1.html</ref> </div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Sand dunes have been found in many places on Mars. The presence of dunes shows that the planet has an atmosphere with wind, for dunes require wind to pile up the sand. Most dunes on Mars are black because of the weathering of the volcanic rock basalt.<ref>http://hirise.lpl.arizona.edu/ESP_016459_1830</ref> <ref> Michael H. Carr (2006). The surface of Mars. Cambridge University Press. ISBN 978-0-521-87201-0.</ref> Black sand can be found on Earth on Hawaii and on some tropical South Pacific islands.<ref>https://www.desertusa.com/desert-activity/sand-dune-wind1.html</ref> </div></td></tr>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>ESP 045575 2535dunesbottom.jpg|Dunes, as seen by HiRISE under HiWish program</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>ESP 045575 2535dunesbottom.jpg|Dunes, as seen by HiRISE under HiWish program</div></td></tr>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[[File:45575 2535duneboulders.jpg|600pxr|Boulder and boulder tracks The arrow shows a boulder that has made a track in the sand as it rolled down dune.]]</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[[File:45575 2535duneboulders.jpg|600pxr|Boulder and boulder tracks The arrow shows a boulder that has made a track in the sand as it rolled down dune.]]</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del class="diffchange diffchange-inline"> </del>Boulder and boulder tracks The arrow shows a boulder that has made a track in the sand as it rolled down dune.</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline"> </ins>Boulder and boulder tracks The arrow shows a boulder that has made a track in the sand as it rolled down dune.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[[File:45575 2535dunebouldertracks.jpg|600pxr|Boulders and tracks, as seen by HiRISE under[[ HiWish program]] The arrows show a boulders that have produced a track by rolling down dune.]]</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[[File:45575 2535dunebouldertracks.jpg|600pxr|Boulders and tracks, as seen by HiRISE under[[ HiWish program]] The arrows show a boulders that have produced a track by rolling down dune.]]</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del class="diffchange diffchange-inline"> </del>Boulders and tracks, as seen by HiRISE <del class="diffchange diffchange-inline">under[[ HiWish program]] </del> The arrows show a boulders that have produced a track by rolling down dune.</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline"> </ins>Boulders and tracks, as seen by HiRISE The arrows show a boulders that have produced a track by rolling down dune.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== See also ==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== See also ==</div></td></tr>
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</table>Suitupshowuphttp://marspedia.org/index.php?title=Mare_Boreum_quadrangle&diff=138594&oldid=prevSuitupandshowup: /* Ice cap */ added image2021-09-15T15:56:38Z<p><span dir="auto"><span class="autocomment">Ice cap: </span> added image</span></p>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>ESP 052405 2595icelayersclosecolor.jpg|Close, color view of layers in northern ice cap, as seen by HiRISE under HiWish program</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>ESP 052405 2595icelayersclosecolor.jpg|Close, color view of layers in northern ice cap, as seen by HiRISE under HiWish program</div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;"></ins></div></td></tr>
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</table>Suitupandshowuphttp://marspedia.org/index.php?title=Mare_Boreum_quadrangle&diff=135601&oldid=prevSuitupandshowup: /* Freezing of atmosphere */ added ref2020-04-17T15:40:27Z<p><span dir="auto"><span class="autocomment">Freezing of atmosphere: </span> added ref</span></p>
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</tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l54" >Line 54:</td>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Every Martian year, part of the atmosphere freezes out. Research based on slight changes in the orbits of spacecraft around Mars over 16 years found that when one hemisphere experiences winter, approximately 3 trillion to 4 trillion tons of carbon dioxide freezes out of the atmosphere onto the northern and southern polar caps. This represents 12 to 16 percent of the mass of the entire Martian atmosphere. These observation support predictions from the Mars Global Reference Atmospheric Model—2010. which predicts climate variations.<ref>NASA/Goddard Space Flight Center. "New gravity map gives best view yet inside Mars." ScienceDaily. ScienceDaily, 21 March 2016. https://www.sciencedaily.com/releases/2016/03/160321154013.htm.</ref> <ref>Antonio Genova, Sander Goossens, Frank G. Lemoine, Erwan Mazarico, Gregory A. Neumann, David E. Smith, Maria T. Zuber. Seasonal and static gravity field of Mars from MGS, Mars Odyssey and MRO radio science. Icarus, 2016; 272: 228 DOI: 10.1016/j.icarus.2016.02.05</ref></div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Every Martian year, part of the atmosphere freezes out. Research based on slight changes in the orbits of spacecraft around Mars over 16 years found that when one hemisphere experiences winter, approximately 3 trillion to 4 trillion tons of carbon dioxide freezes out of the atmosphere onto the northern and southern polar caps. This represents 12 to 16 percent of the mass of the entire Martian atmosphere. These observation support predictions from the Mars Global Reference Atmospheric Model—2010. which predicts climate variations.<ref>NASA/Goddard Space Flight Center. "New gravity map gives best view yet inside Mars." ScienceDaily. ScienceDaily, 21 March 2016. https://www.sciencedaily.com/releases/2016/03/160321154013.htm.</ref> <ref>Antonio Genova, Sander Goossens, Frank G. Lemoine, Erwan Mazarico, Gregory A. Neumann, David E. Smith, Maria T. Zuber. Seasonal and static gravity field of Mars from MGS, Mars Odyssey and MRO radio science. Icarus, 2016; 272: 228 DOI: 10.1016/j.icarus.2016.02.05</ref></div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;"></del></div></td><td colspan="2"> </td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Proof for ocean==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Proof for ocean==</div></td></tr>
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</table>Suitupandshowuphttp://marspedia.org/index.php?title=Mare_Boreum_quadrangle&diff=135442&oldid=prevSuitupandshowup at 14:55, 25 March 20202020-03-25T14:55:18Z<p></p>
<table class="diff diff-contentalign-left" data-mw="interface">
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<td colspan="2" style="background-color: #fff; color: #222; text-align: center;">Revision as of 14:55, 25 March 2020</td>
</tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l31" >Line 31:</td>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Both polar caps show layered features that result from seasonal melting and deposition of ice together with dust from Martian dust storms. These polar layered deposits lie under the permanent polar caps. Information about the past climate of Mars may eventually be revealed in these layers, just as tree ring patterns and ice core data do on Earth. One large valley, Chasma Boreale runs halfway across the cap. It is about 100 km wide and up to 2 km deep—that's deeper than Earth's Grand Canyon.<ref>ISBN|978-0-521-85226-5</ref></div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Both polar caps show layered features that result from seasonal melting and deposition of ice together with dust from Martian dust storms. These polar layered deposits lie under the permanent polar caps. Information about the past climate of Mars may eventually be revealed in these layers, just as tree ring patterns and ice core data do on Earth. One large valley, Chasma Boreale runs halfway across the cap. It is about 100 km wide and up to 2 km deep—that's deeper than Earth's Grand Canyon.<ref>ISBN|978-0-521-85226-5</ref></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>When the tilt or obliquity changes, the size of the polar caps change. When the tilt is at its highest, the poles receive far more sunlight and for more hours each day. The extra sunlight causes the ice to melt, so much so that it could cover parts of the surface in 10 m of ice. Much evidence has been found for glaciers that probably formed when this tilt-induced climate change occurred.<ref>"ISBN 978-0-521-86698-9">isbn = 978-0-521-86698-9|title = The Martian Surface: Composition, Mineralogy and Physical Properties|last1 = Bell|first1 = Jim|date = 2008-06-05</ref></div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>When the tilt or obliquity changes, the size of the polar caps change. When the tilt is at its highest, the poles receive far more sunlight and for more hours each day. The extra sunlight causes the ice to melt, so much so that it could cover parts of the surface in 10 m of ice <ins class="diffchange diffchange-inline">(by one estimate)</ins>. Much evidence has been found for glaciers that probably formed when this tilt-induced climate change occurred.<ref>"ISBN 978-0-521-86698-9">isbn = 978-0-521-86698-9|title = The Martian Surface: Composition, Mineralogy and Physical Properties|last1 = Bell|first1 = Jim|date = 2008-06-05</ref></div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>The Phoenix spacecraft <del class="diffchange diffchange-inline">landed </del>landed on Vastitas Borealis within the Mare Boreum quadrangle at 68.218830° N and 234.250778° E on May 25, 2008.<ref> Lakdawalla Emily. 2008-05-27. Phoenix Sol 2 press conference, in a nutshell. Planetary Society weblog. Planetary Society. http://planetary.org/blog/article/00001470/</ref></div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>The Phoenix spacecraft landed on Vastitas Borealis within the Mare Boreum quadrangle at 68.218830° N and 234.250778° E on May 25, 2008.<ref> Lakdawalla Emily. 2008-05-27. Phoenix Sol 2 press conference, in a nutshell. Planetary Society weblog. Planetary Society. http://planetary.org/blog/article/00001470/</ref></div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>The probe collected and analyzed soil samples in an effort to detect water and determine how hospitable the planet might once have been for life to <del class="diffchange diffchange-inline">grow</del>. It remained active there until winter conditions became too harsh around five months later.<ref>https://www.newscientist.com/article/dn13661-mars-lander-aims-for-touchdown-in-green-valley.html|title=Mars lander aims for touchdown in 'Green Valley'|New Scientist</ref></div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>The probe collected and analyzed soil samples in an effort to detect water and determine how hospitable the planet might once have been for life to <ins class="diffchange diffchange-inline">thrive</ins>. It remained active there until winter conditions became too harsh around five months later.<ref>https://www.newscientist.com/article/dn13661-mars-lander-aims-for-touchdown-in-green-valley.html|title=Mars lander aims for touchdown in 'Green Valley'|New Scientist</ref></div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>After the mission ended the journal ''Science'' reported that chloride, bicarbonate, magnesium, sodium potassium, calcium, and possibly sulfate were detected in the samples analyzed by Phoenix. The pH was narrowed down to 7.7±0.5. Perchlorate (ClO<sub>4</sub>), a strong oxidizer at elevated temperatures, was detected. This was a significant discovery because the chemical has the potential of being used for rocket fuel and as a source of oxygen for future colonists. <del class="diffchange diffchange-inline">Also, under </del>certain conditions perchlorate can inhibit life; however some microorganisms obtain energy from the substance (by anaerobic reduction). The chemical when mixed with water can greatly lower freezing points, in a manner similar to how salt is applied to roads to melt ice. So, perchlorate may be allowing small amounts of liquid water to form on Mars today. Gullies, which are common in certain areas of Mars, may have formed from perchlorate melting ice and causing water to erode soil on steep slopes.<ref>Hecht, M. et al. 2009. Detection of Perchlorate and the Soluble Chemistry of Martian Soil at the Phoenix Lander Site. Science: 325. 64–67</ref> Much direct evidence was found for water at this location.<ref>Smith, P., et al. 2009. H<sub>2</sub>O at the Phoenix Landing Site. Science: 325, 58-61.</ref></div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">Phoenix measured the chemistry of the soil. </ins>After the mission ended the journal ''Science'' reported that chloride, bicarbonate, magnesium, sodium potassium, calcium, and possibly sulfate were detected in the samples analyzed by Phoenix. The <ins class="diffchange diffchange-inline">value for the </ins>pH was narrowed down to 7.7±0.5.</div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>Perchlorate (ClO<sub>4</sub>), a strong oxidizer at elevated temperatures, was detected. This was a significant discovery because the chemical has the potential of being used for rocket fuel and as a source of oxygen for future colonists. <ins class="diffchange diffchange-inline">Under </ins>certain conditions perchlorate can inhibit life; however some microorganisms obtain energy from the substance (by anaerobic reduction). The chemical when mixed with water can greatly lower freezing points, in a manner similar to how salt is applied to roads to melt ice. So, perchlorate may be allowing small amounts of liquid water to form on Mars today. Gullies, which are common in certain areas of Mars, may have formed from perchlorate melting ice and causing water to erode soil on steep slopes.<ref>Hecht, M. et al. 2009. Detection of Perchlorate and the Soluble Chemistry of Martian Soil at the Phoenix Lander Site. Science: 325. 64–67</ref> Much direct evidence was found for water at this location.<ref>Smith, P., et al. 2009. H<sub>2</sub>O at the Phoenix Landing Site. Science: 325, 58-61.</ref></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div><gallery class="center" widths="380px" heights="360px"></div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div><gallery class="center" widths="380px" heights="360px"></div></td></tr>
<tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l50" >Line 50:</td>
<td colspan="2" class="diff-lineno">Line 53:</td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Freezing of atmosphere==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Freezing of atmosphere==</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>Research based on slight changes in the orbits of spacecraft around Mars over 16 years found that when one hemisphere experiences winter, approximately 3 trillion to 4 trillion tons of carbon dioxide freezes out of the atmosphere onto the northern and southern polar caps. This represents 12 to 16 percent of the mass of the entire Martian atmosphere. These observation support predictions from the Mars Global Reference Atmospheric Model—2010.<ref>NASA/Goddard Space Flight Center. "New gravity map gives best view yet inside Mars." ScienceDaily. ScienceDaily, 21 March 2016. https://www.sciencedaily.com/releases/2016/03/160321154013.htm.</ref> <ref>Antonio Genova, Sander Goossens, Frank G. Lemoine, Erwan Mazarico, Gregory A. Neumann, David E. Smith, Maria T. Zuber. Seasonal and static gravity field of Mars from MGS, Mars Odyssey and MRO radio science. Icarus, 2016; 272: 228 DOI: 10.1016/j.icarus.2016.02.05</ref></div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">Every Martian year, part of the atmosphere freezes out. </ins>Research based on slight changes in the orbits of spacecraft around Mars over 16 years found that when one hemisphere experiences winter, approximately 3 trillion to 4 trillion tons of carbon dioxide freezes out of the atmosphere onto the northern and southern polar caps. This represents 12 to 16 percent of the mass of the entire Martian atmosphere. These observation support predictions from the Mars Global Reference Atmospheric Model—2010<ins class="diffchange diffchange-inline">. which predicts climate variations</ins>.<ref>NASA/Goddard Space Flight Center. "New gravity map gives best view yet inside Mars." ScienceDaily. ScienceDaily, 21 March 2016. https://www.sciencedaily.com/releases/2016/03/160321154013.htm.</ref> <ref>Antonio Genova, Sander Goossens, Frank G. Lemoine, Erwan Mazarico, Gregory A. Neumann, David E. Smith, Maria T. Zuber. Seasonal and static gravity field of Mars from MGS, Mars Odyssey and MRO radio science. Icarus, 2016; 272: 228 DOI: 10.1016/j.icarus.2016.02.05</ref></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Proof for ocean==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Proof for ocean==</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>Strong evidence for a one time ancient ocean was found in Mare Boreum near the North pole (as well as the South pole). In March 2015, a team of scientists published results showing that this region was highly enriched with deuterium<del class="diffchange diffchange-inline">, </del>heavy hydrogen<del class="diffchange diffchange-inline">, </del>by seven times as much as the Earth. This means that Mars has lost a volume of water 6.5 times what is stored in today's polar caps. The water for a time would have formed an ocean in the low-lying Mare Boreum. The amount of water could have covered the planet about 140 meters, but was probably in an ocean that in places would be almost 1 mile deep.</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>Strong evidence for a one time ancient ocean was found in Mare Boreum near the North pole (as well as the South pole). In March 2015, a team of scientists published results showing that this region was highly enriched with deuterium <ins class="diffchange diffchange-inline">(</ins>heavy hydrogen<ins class="diffchange diffchange-inline">) </ins>by seven times as much as the Earth. This means that Mars has lost a volume of water 6.5 times what is stored in today's polar caps. The water for a time would have formed an ocean in the low-lying Mare Boreum. The amount of water could have covered the planet about 140 meters, but was probably in an ocean that in places would be almost 1 mile deep.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>This international team used ESO's Very Large Telescope, along with instruments at the W. M. Keck Observatory and the NASA Infrared Telescope Facility, to map out different forms of water in Mars's atmosphere over a six-year period.<ref>https://www.sciencedaily.com/releases/2015/03/150305140447.htm</ref><ref>. Villanueva, L., Mumma, R. Novak, H. Käufl, P. Hartogh, T. Encrenaz, A. Tokunaga, A. Khayat, M. Smith. Strong water isotopic anomalies in the martian atmosphere: Probing current and ancient reservoirs. Science, 2015 DOI: 10.1126/science.aaa3630</ref></div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>This international team used ESO's Very Large Telescope, along with instruments at the W. M. Keck Observatory and the NASA Infrared Telescope Facility, to map out different forms of water in Mars's atmosphere over a six-year period.<ref>https://www.sciencedaily.com/releases/2015/03/150305140447.htm</ref><ref>. Villanueva, L., Mumma, R. Novak, H. Käufl, P. Hartogh, T. Encrenaz, A. Tokunaga, A. Khayat, M. Smith. Strong water isotopic anomalies in the martian atmosphere: Probing current and ancient reservoirs. Science, 2015 DOI: 10.1126/science.aaa3630</ref></div></td></tr>
<tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l72" >Line 72:</td>
<td colspan="2" class="diff-lineno">Line 75:</td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Sand dunes have been found in many places on Mars. The presence of dunes shows that the planet has an atmosphere with wind, for dunes require wind to pile up the sand. Most dunes on Mars are black because of the weathering of the volcanic rock basalt.<ref>http://hirise.lpl.arizona.edu/ESP_016459_1830</ref> <ref> Michael H. Carr (2006). The surface of Mars. Cambridge University Press. ISBN 978-0-521-87201-0.</ref> Black sand can be found on Earth on Hawaii and on some tropical South Pacific islands.<ref>https://www.desertusa.com/desert-activity/sand-dune-wind1.html</ref> </div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Sand dunes have been found in many places on Mars. The presence of dunes shows that the planet has an atmosphere with wind, for dunes require wind to pile up the sand. Most dunes on Mars are black because of the weathering of the volcanic rock basalt.<ref>http://hirise.lpl.arizona.edu/ESP_016459_1830</ref> <ref> Michael H. Carr (2006). The surface of Mars. Cambridge University Press. ISBN 978-0-521-87201-0.</ref> Black sand can be found on Earth on Hawaii and on some tropical South Pacific islands.<ref>https://www.desertusa.com/desert-activity/sand-dune-wind1.html</ref> </div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>Sand is common on Mars due to the old age of the surface that has <del class="diffchange diffchange-inline">allowed </del>rocks to erode into sand. Dunes on Mars have been observed to move many meters.<ref>https://www.youtube.com/watch?v=ur_TeOs3S64</ref><ref>https://uanews.arizona.edu/story/the-flowing-sands-of-mars</ref> In this process, sand moves up the windward side and then falls down the leeward side of the dune, thus caused the dune to go toward the leeward side (or slip face).<ref>Namowitz, S., Stone, D. 1975. earth science the world we live in. American Book Company. New York.</ref></div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>Sand is common on Mars due to the old age of the surface that has <ins class="diffchange diffchange-inline">given </ins>rocks <ins class="diffchange diffchange-inline">a long, long time </ins>to erode into sand. Dunes on Mars have been observed to move many meters.<ref>https://www.youtube.com/watch?v=ur_TeOs3S64</ref> <ref>https://uanews.arizona.edu/story/the-flowing-sands-of-mars</ref> In this process, sand moves up the windward side and then falls down the leeward side of the dune, thus caused the dune to go toward the leeward side (or slip face).<ref>Namowitz, S., Stone, D. 1975. earth science the world we live in. American Book Company. New York.</ref></div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>When images are enlarged, some dunes on Mars display ripples on their surfaces.<ref>https://www.jpl.nasa.gov/news/news.php?feature=6551</ref> <del class="diffchange diffchange-inline">These are caused by sand grains rolling and bouncing up the windward surface of a dune. The bouncing grains tend to land on the windward side of each ripple. The grains do not bounce very high so it does not take much to stop them.</del></div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>When images are enlarged, some dunes on Mars display ripples on their surfaces.<ref>https://www.jpl.nasa.gov/news/news.php?feature=6551</ref> </div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div><gallery class="center" widths="380px" heights="360px"></div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div><gallery class="center" widths="380px" heights="360px"></div></td></tr>
<tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l82" >Line 82:</td>
<td colspan="2" class="diff-lineno">Line 85:</td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>43821 2555defrostingdune2.jpg|Defrosting surface Frost is disappearing in patches from a dune and from the surrounding surface. Note: the north side (side near top) has not defrosted because the sun is coming from the other side.</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>43821 2555defrostingdune2.jpg|Defrosting surface Frost is disappearing in patches from a dune and from the surrounding surface. Note: the north side (side near top) has not defrosted because the sun is coming from the other side.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>ESP 045575 2535dunesbottom.jpg|<del class="diffchange diffchange-inline">Closer view of dunes</del>, as seen by HiRISE under HiWish program</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>ESP 045575 2535dunesbottom.jpg|<ins class="diffchange diffchange-inline">Dunes</ins>, as seen by HiRISE under HiWish program</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div> </div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l96" >Line 96:</td>
<td colspan="2" class="diff-lineno">Line 99:</td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== See also ==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== See also ==</div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;"></ins></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>*[[High Resolution Imaging Science Experiment (HiRISE)]]</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>*[[High Resolution Imaging Science Experiment (HiRISE)]]</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>*[[HiWish program]]</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>*[[HiWish program]]</div></td></tr>
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</table>Suitupandshowuphttp://marspedia.org/index.php?title=Mare_Boreum_quadrangle&diff=135347&oldid=prevSuitupandshowup at 13:49, 22 March 20202020-03-22T13:49:40Z<p></p>
<table class="diff diff-contentalign-left" data-mw="interface">
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<td colspan="2" style="background-color: #fff; color: #222; text-align: center;">Revision as of 13:49, 22 March 2020</td>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The Mare Boreum quadrangle contains an ice cap and several large prominent craters. The main features in this quadrangle are Korolov Crater, Lomonosov Crater, and Chasma Boreale. The Phoenix spacecraft landed here on May 25, 2008.</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The Mare Boreum quadrangle contains an ice cap and several large prominent craters. The main features in this quadrangle are Korolov Crater, Lomonosov Crater, and Chasma Boreale. The Phoenix spacecraft landed here on May 25, 2008.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The Mare Boreum quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) and is also referred to as MC-1 (Mars Chart-1).<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> Its name derives from an older name for a feature that is now called Planum Boreum, a large plain surrounding the polar cap.<ref>Patrick Moore and Robin Rees, ed. ''Patrick Moore's Data Book of Astronomy'' (Cambridge University Press, 2011), p. 130.</ref></div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The Mare Boreum quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) and is also referred to as MC-1 (Mars Chart-1).<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> Its name derives from an older name for a feature that is now called Planum Boreum, a large plain surrounding the polar cap.<ref>Patrick Moore and Robin Rees, ed. ''Patrick Moore's Data Book of Astronomy'' (Cambridge University Press, 2011), p. 130.</ref></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;"></ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">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. </ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;"></ins></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The quadrangle covers all of the Martian surface north of latitude 65°. It includes the north polar ice cap, which has a swirl pattern and is roughly 1100 km across. [[Mariner 9]] in 1972 discovered a belt of sand dunes that ring the polar ice deposits. The belt is 500 km across in some places and may be the largest dune field in the solar system.<ref>Hartmann, W. 2003. A Traveler's Guide to Mars. Workman Publishing. NY NY.</ref> The ice cap is surrounded by the vast plains of Planum Boreum and Vastitas Borealis. Close to the pole, there is a large valley, Chasma Boreale, that may have been formed from water melting from the ice cap.<ref>Clifford, S. 1987. Polar basal melting on Mars. J. Geophys. Res. 92: 9135-9152.</ref> An alternative view is that it was made by winds coming off the cold pole.<ref>Howard, A. 2000. The role of eolian processes in forming surface features of the martian polar layered deposits. Icarus. 144: 267-288.</ref> <ref>Edgett, K. et al. 2003. Mars landscape evolution: influence of stratigraphy on geomorphology of the north polar region. Geomorphology. 52: 289-298.</ref> Another prominent feature is a smooth rise, formerly called Olympia Planitia. In the summer, a dark collar around the residual cap becomes visible; it is mostly caused by dunes.<ref>Michael H. Carr|title=The surface of Mars|url=https://books.google.com/books?id=uLHlJ6sjohwC|accessdate=21 March 2011|year=2006|publisher=Cambridge University Press|isbn=978-0-521-87201-0</ref> The quadrangle includes some very large craters that stand out in the north because the area is smooth. In other words, they really stand out. These large craters are Lomonosov, and Korolev. Although smaller, the crater Stokes is also prominent.</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The quadrangle covers all of the Martian surface north of latitude 65°. It includes the north polar ice cap, which has a swirl pattern and is roughly 1100 km across. [[Mariner 9]] in 1972 discovered a belt of sand dunes that ring the polar ice deposits. The belt is 500 km across in some places and may be the largest dune field in the solar system.<ref>Hartmann, W. 2003. A Traveler's Guide to Mars. Workman Publishing. NY NY.</ref> The ice cap is surrounded by the vast plains of Planum Boreum and Vastitas Borealis. Close to the pole, there is a large valley, Chasma Boreale, that may have been formed from water melting from the ice cap.<ref>Clifford, S. 1987. Polar basal melting on Mars. J. Geophys. Res. 92: 9135-9152.</ref> An alternative view is that it was made by winds coming off the cold pole.<ref>Howard, A. 2000. The role of eolian processes in forming surface features of the martian polar layered deposits. Icarus. 144: 267-288.</ref> <ref>Edgett, K. et al. 2003. Mars landscape evolution: influence of stratigraphy on geomorphology of the north polar region. Geomorphology. 52: 289-298.</ref> Another prominent feature is a smooth rise, formerly called Olympia Planitia. In the summer, a dark collar around the residual cap becomes visible; it is mostly caused by dunes.<ref>Michael H. Carr|title=The surface of Mars|url=https://books.google.com/books?id=uLHlJ6sjohwC|accessdate=21 March 2011|year=2006|publisher=Cambridge University Press|isbn=978-0-521-87201-0</ref> The quadrangle includes some very large craters that stand out in the north because the area is smooth. In other words, they really stand out. These large craters are Lomonosov, and Korolev. Although smaller, the crater Stokes is also prominent.</div></td></tr>
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</table>Suitupandshowuphttp://marspedia.org/index.php?title=Mare_Boreum_quadrangle&diff=135197&oldid=prevSuitupandshowup: /* See also */2020-03-19T12:23:38Z<p><span dir="auto"><span class="autocomment">See also</span></span></p>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>*[[Layers on Mars]]</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>*[[Layers on Mars]]</div></td></tr>
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</table>Suitupandshowuphttp://marspedia.org/index.php?title=Mare_Boreum_quadrangle&diff=135196&oldid=prevSuitupandshowup: /* See Also */ added to list2020-03-19T12:22:04Z<p><span dir="auto"><span class="autocomment">See Also: </span> added to list</span></p>
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</table>Suitupandshowuphttp://marspedia.org/index.php?title=Mare_Boreum_quadrangle&diff=135195&oldid=prevSuitupandshowup: /* Dunes */2020-03-19T12:19:29Z<p><span dir="auto"><span class="autocomment">Dunes</span></span></p>
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<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del class="diffchange diffchange-inline"> </del>Defrosting dunes and ice in troughs of polygons, as seen by HiRISE under [[HiWish program]]</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline"> </ins>Defrosting dunes and ice in troughs of polygons, as seen by HiRISE under [[HiWish program]]</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Sand dunes have been found in many places on Mars. The presence of dunes shows that the planet has an atmosphere with wind, for dunes require wind to pile up the sand. Most dunes on Mars are black because of the weathering of the volcanic rock basalt.<ref>http://hirise.lpl.arizona.edu/ESP_016459_1830</ref> <ref> Michael H. Carr (2006). The surface of Mars. Cambridge University Press. ISBN 978-0-521-87201-0.</ref> Black sand can be found on Earth on Hawaii and on some tropical South Pacific islands.<ref>https://www.desertusa.com/desert-activity/sand-dune-wind1.html</ref> </div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Sand dunes have been found in many places on Mars. The presence of dunes shows that the planet has an atmosphere with wind, for dunes require wind to pile up the sand. Most dunes on Mars are black because of the weathering of the volcanic rock basalt.<ref>http://hirise.lpl.arizona.edu/ESP_016459_1830</ref> <ref> Michael H. Carr (2006). The surface of Mars. Cambridge University Press. ISBN 978-0-521-87201-0.</ref> Black sand can be found on Earth on Hawaii and on some tropical South Pacific islands.<ref>https://www.desertusa.com/desert-activity/sand-dune-wind1.html</ref> </div></td></tr>
<tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l90" >Line 90:</td>
<td colspan="2" class="diff-lineno">Line 90:</td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[[File:45575 2535dunebouldertracks.jpg|600pxr|Boulders and tracks, as seen by HiRISE under[[ HiWish program]] The arrows show a boulders that have produced a track by rolling down dune.]]</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[[File:45575 2535dunebouldertracks.jpg|600pxr|Boulders and tracks, as seen by HiRISE under[[ HiWish program]] The arrows show a boulders that have produced a track by rolling down dune.]]</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div> Boulders and tracks, as seen by HiRISE under[[ HiWish program]] The arrows show a boulders that have produced a track by rolling down dune. </div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> Boulders and tracks, as seen by HiRISE under[[ HiWish program]] The arrows show a boulders that have produced a track by rolling down dune.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== See also ==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>== See also ==</div></td></tr>
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