Lyot crater, featuring a central peak in the middle, stands out on the flat plains of Vastitas Borealis, which is generally flat and smooth with few large craters.[2] Lyot is the deepest point in the northern hemisphere of Mars.[3] To the south are the Deuteronilus Mensae, and further to the southeast are Protonilus Mensae. To the west is the smaller Micoud crater, and to the east-southeast is Moreux crater.
Research published in 2009 describes evidence for liquid water in Lyot in the past.[4]
Many channels have been found near Lyot Crater. Research, published in 2017, concluded that the channels were made from water released when the hot ejecta landed on a layer of ice that was 20 to 300 meters thick. Calculations suggest that the ejecta would have had a temperature of at least 250 °F (121 °C). The valleys seem to start from beneath the ejecta near the outer edge of the ejecta. One evidence for this idea is that there are few secondary craters nearby. Few secondary craters were formed because most landed on ice and did not affect the ground below. The ice accumulated in the area when the climate was different. The tilt or obliquity of the axis changes frequently. During periods of greater tilt, ice from the poles is redistributed to the mid-latitudes. The existence of these channels is unusual because although Mars used to have water in rivers, lakes, and an ocean, these features have been dated to the Noachian and Hesperian periods—4 to 3 billion years ago.[5][6][7]
Images from Mars Reconnaissance Orbiter show valleys carved by rivers on the floor of Lyot crater. Scientists are excited because the rivers seem to have formed more recently than others on Mars; water could have flowed in them only 1.25 million years ago. The source of the water is believed to have been ice from nearby glaciers. The river valleys are over 250 metres (820 ft) wide and tens of kilometers long.[8]
Wide view of channels in Lyot crater, as seen by HiRISE unser HiWish program
Close view of channels in Lyot crater, as seen by HiRISE under HiWish program
Close view of channels in Lyot crater, as seen by HiRISE under HiWish program
Curved channel in Lyot crater, as seen by HiRISE under HiWish program
Lyot crater with elevations exaggerated showing distribution of channels caused by hot ejecta melting ice.
Dust devil tracksedit
Many areas on Mars, including Lyot, experience the passage of giant dust devils. A thin coating of fine bright dust covers most of the Martian surface. When a dust devil goes by it blows away the coating and exposes the underlying dark surface. These dust devils have been seen from the ground and high overhead from orbit.
^"Lyot". Gazetteer of Planetary Nomenclature. USGS Astrogeology Research Program.
^U.S. department of the Interior U.S. Geological Survey, Topographic Map of the Eastern Region of Mars M 15M 0/270 2AT, 1991
^"Mars: What We Know About the Red Planet". Space.com. October 2021.
^Dickson, J. L.; Fassett, C. I.; Head, J. W. (2009). "Amazonian‐aged fluvial valley systems in a climatic microenvironment on Mars: Melting of ice deposits on the interior of Lyot Crater". Geophysical Research Letters. 36 (8): L08201. Bibcode:2009GeoRL..36.8201D. doi:10.1029/2009GL037472.
^Weiss, David K. (2017). "Extensive Amazonian-aged fluvial channels on Mars: Evaluating the role of Lyot crater in their formation". Geophysical Research Letters. 44 (11): 5336–5344. Bibcode:2017GeoRL..44.5336W. doi:10.1002/2017GL073821.
^Weiss, D.; et al. (2017). "Extensive Amazonian-aged fluvial channels on Mars: Evaluating the role of Lyot crater in their formation". Geophysical Research Letters. 44 (11): 5336–5344. Bibcode:2017GeoRL..44.5336W. doi:10.1002/2017GL073821.
^"Hot Rocks Led to Relatively Recent Water-Carved Valleys on Mars - SpaceRef".
^"Rivers Might Have Flowed Recently on Mars". Space.com. 14 May 2009.
External linksedit
Wikimedia Commons has media related to Lyot (Martian crater).
lyot, martian, crater, this, article, about, crater, mars, lunar, crater, lyot, lunar, crater, lyot, large, peak, ring, crater, vastitas, borealis, region, mars, located, north, latitude, west, longitude, within, ismenius, lacus, quadrangle, diameter, name, re. This article is about the crater on Mars For the lunar crater see Lyot lunar crater Lyot is a large peak ring crater in the Vastitas Borealis region of Mars located at 50 8 north latitude and 330 7 west longitude within the Ismenius Lacus quadrangle It is 236 km in diameter Its name refers to Bernard Lyot a French astronomer 1897 1952 1 LyotShaded relief topographic map of LyotPlanetMarsRegionIsmenius Lacus quadrangleCoordinates50 48 N 330 42 W 50 8 N 330 7 W 50 8 330 7QuadrangleIsmenius LacusDiameter236 km 147 mi EponymBernard Lyot French astronomer 1897 1952 Lyot crater featuring a central peak in the middle stands out on the flat plains of Vastitas Borealis which is generally flat and smooth with few large craters 2 Lyot is the deepest point in the northern hemisphere of Mars 3 To the south are the Deuteronilus Mensae and further to the southeast are Protonilus Mensae To the west is the smaller Micoud crater and to the east southeast is Moreux crater Viking Orbiter 2 mosaic Research published in 2009 describes evidence for liquid water in Lyot in the past 4 Many channels have been found near Lyot Crater Research published in 2017 concluded that the channels were made from water released when the hot ejecta landed on a layer of ice that was 20 to 300 meters thick Calculations suggest that the ejecta would have had a temperature of at least 250 F 121 C The valleys seem to start from beneath the ejecta near the outer edge of the ejecta One evidence for this idea is that there are few secondary craters nearby Few secondary craters were formed because most landed on ice and did not affect the ground below The ice accumulated in the area when the climate was different The tilt or obliquity of the axis changes frequently During periods of greater tilt ice from the poles is redistributed to the mid latitudes The existence of these channels is unusual because although Mars used to have water in rivers lakes and an ocean these features have been dated to the Noachian and Hesperian periods 4 to 3 billion years ago 5 6 7 Contents 1 Former rivers 2 Dust devil tracks 3 Gallery 4 Interactive Mars map 5 See also 6 References 7 External linksFormer rivers editImages from Mars Reconnaissance Orbiter show valleys carved by rivers on the floor of Lyot crater Scientists are excited because the rivers seem to have formed more recently than others on Mars water could have flowed in them only 1 25 million years ago The source of the water is believed to have been ice from nearby glaciers The river valleys are over 250 metres 820 ft wide and tens of kilometers long 8 nbsp Wide view of channels in Lyot crater as seen by HiRISE unser HiWish program nbsp Close view of channels in Lyot crater as seen by HiRISE under HiWish program nbsp Close view of channels in Lyot crater as seen by HiRISE under HiWish program nbsp Curved channel in Lyot crater as seen by HiRISE under HiWish program nbsp Channels in Lyot as seen by HiRISE nbsp Lyot crater with elevations exaggerated showing distribution of channels caused by hot ejecta melting ice Dust devil tracks editMany areas on Mars including Lyot experience the passage of giant dust devils A thin coating of fine bright dust covers most of the Martian surface When a dust devil goes by it blows away the coating and exposes the underlying dark surface These dust devils have been seen from the ground and high overhead from orbit Gallery edit nbsp MGS image with Lyot at top nbsp Lyot crater dunes as seen by HiRISE Click on image to see light toned deposits and dust devil tracks nbsp Gullies on central uplift of Lyot crater image reprocessed from HiRISE data nbsp MOLA map of Lyot and other nearby craters Colors indicate elevations nbsp Lyot crater gullies as seen by HiRISE nbsp Lyot crater channel as seen by CTX Water carved channels have been spotted in Lyot crater the curved line may be one Interactive Mars map edit nbsp nbsp Interactive image map of the global topography of Mars Hover over the image to see the names of over 60 prominent geographic features and click to link to them Coloring of the base map indicates relative elevations based on data from the Mars Orbiter Laser Altimeter on NASA s Mars Global Surveyor Whites and browns indicate the highest elevations 12 to 8 km followed by pinks and reds 8 to 3 km yellow is 0 km greens and blues are lower elevations down to 8 km Axes are latitude and longitude Polar regions are noted See also Mars Rovers map and Mars Memorial map view discuss See also editList of craters on MarsReferences edit Lyot Gazetteer of Planetary Nomenclature USGS Astrogeology Research Program U S department of the Interior U S Geological Survey Topographic Map of the Eastern Region of Mars M 15M 0 270 2AT 1991 Mars What We Know About the Red Planet Space com October 2021 Dickson J L Fassett C I Head J W 2009 Amazonian aged fluvial valley systems in a climatic microenvironment on Mars Melting of ice deposits on the interior of Lyot Crater Geophysical Research Letters 36 8 L08201 Bibcode 2009GeoRL 36 8201D doi 10 1029 2009GL037472 Weiss David K 2017 Extensive Amazonian aged fluvial channels on Mars Evaluating the role of Lyot crater in their formation Geophysical Research Letters 44 11 5336 5344 Bibcode 2017GeoRL 44 5336W doi 10 1002 2017GL073821 Weiss D et al 2017 Extensive Amazonian aged fluvial channels on Mars Evaluating the role of Lyot crater in their formation Geophysical Research Letters 44 11 5336 5344 Bibcode 2017GeoRL 44 5336W doi 10 1002 2017GL073821 Hot Rocks Led to Relatively Recent Water Carved Valleys on Mars SpaceRef Rivers Might Have Flowed Recently on Mars Space com 14 May 2009 External links edit nbsp Wikimedia Commons has media related to Lyot Martian crater Portal nbsp Solar System Retrieved from https en wikipedia org w index php title Lyot Martian crater amp oldid 1095743175, wikipedia, wiki, book, books, library,
