Deuteronilus Mensae
Encyclopedia
Deuteronilus Mensae is a region on Mars
937 km across and centered at 43.9°N 337.4°W. It covers 344° -325° West and 40°-48° North. Deuteronilus region lies just to the north of Arabia Terra
and is included in the Ismenius Lacus quadrangle
. It is along the dichotomy boundary, that is between the old, heavily cratered southern highlands and the low plains of the northern hemisphere. The region contains flat-topped knobby terrain that may have been formed by glaciers at some time in the past. Deuteronilus Mensae is to the immediate west of Protonilus Mensae
and Ismeniae Fossae. Glacier
s persist in the region in modern times, with at least one glacier estimated to have formed as recently as 100,000 to 10,000 years ago. Recent evidence from the radar
on the Mars Reconnaissance Orbiter
has shown that parts of Deuteronilus Mensae do indeed contain ice.
Ice on the surface of Mars today would immediately sublimate (or change directly into the gas phase). The rocky debris and dust covering ice is likely what has allowed it to survive below the surface for millions of years.
Mars
Mars is the fourth planet from the Sun in the Solar System. The planet is named after the Roman god of war, Mars. It is often described as the "Red Planet", as the iron oxide prevalent on its surface gives it a reddish appearance...
937 km across and centered at 43.9°N 337.4°W. It covers 344° -325° West and 40°-48° North. Deuteronilus region lies just to the north of Arabia Terra
Arabia Terra
Arabia Terra is a large upland region in the north of Mars in that lies mostly in the Arabia quadrangle. It is densely cratered and heavily eroded. This battered topography indicates great age, and Arabia Terra is presumed to be one of the oldest terrains on the planet...
and is included in the Ismenius Lacus quadrangle
Ismenius Lacus quadrangle
The Ismenius Lacus quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey Astrogeology Research Program. The quadrangle is located in the northwestern portion of Mars’ eastern hemisphere and covers 0° to 60° east longitude and 30° to 65° north...
. It is along the dichotomy boundary, that is between the old, heavily cratered southern highlands and the low plains of the northern hemisphere. The region contains flat-topped knobby terrain that may have been formed by glaciers at some time in the past. Deuteronilus Mensae is to the immediate west of Protonilus Mensae
Protonilus Mensae
Protonilus Mensae is an area of Mars in the Ismenius Lacus quadrangle. It is centered on the coordinates of 43.86° N and 49.4° E. Its western and eastern longitudes are 37° E and 59.7° E. North and south latitudes are 47.06° N and 39.87° N. Protonilus Mensae is between Deuteronilus Mensae and...
and Ismeniae Fossae. Glacier
Glacier
A glacier is a large persistent body of ice that forms where the accumulation of snow exceeds its ablation over many years, often centuries. At least 0.1 km² in area and 50 m thick, but often much larger, a glacier slowly deforms and flows due to stresses induced by its weight...
s persist in the region in modern times, with at least one glacier estimated to have formed as recently as 100,000 to 10,000 years ago. Recent evidence from the radar
SHARAD
SHARAD is a subsurface sounding radar embarked on the Mars Reconnaissance Orbiter probe. It complements the MARSIS instrument on Mars Express, providing lower penetration capabilities but much finer resolution .SHARAD is developed under the responsibility of the Italian Space Agency SHARAD (Mars...
on the Mars Reconnaissance Orbiter
Mars Reconnaissance Orbiter
Mars Reconnaissance Orbiter is a NASA multipurpose spacecraft designed to conduct reconnaissance and Exploration of Mars from orbit...
has shown that parts of Deuteronilus Mensae do indeed contain ice.
Source of Ice
It is now widely believed that ice accumulated in many area of Mars, including Deuteronilus Mensae, when planet's orbital tilt was much different than it is now (the axis of Mars has considerable "wobble," meaning its angle changes over time). A few million years ago, the tilt of the axis of Mars was 45 degrees instead of its present 25 degrees. Its’ tilt, also called obliquity, varies greatly because its two tiny moons cannot stabilize it, like our relatively large moon does to the Earth. During periods of high tilt, the ice caps at the poles disappear, the atmosphere thickens, and the moisture in the atmosphere goes up. These conditions cause snow and frost to appear on the surface. Some of the moisture would have coated dust grains until the grains would be too heavy to be held up in the atmosphere; they would then fall and accumulate on the surface. Just plain snow would have also added to the mix.Ice on the surface of Mars today would immediately sublimate (or change directly into the gas phase). The rocky debris and dust covering ice is likely what has allowed it to survive below the surface for millions of years.
See also
- Geology of MarsGeology of MarsThe geology of Mars is the scientific study of the surface, crust, and interior of the planet Mars. It emphasizes the composition, structure, history, and physical processes that shape the planet. It is fully analogous to the field of terrestrial geology. In planetary science, the term geology is...
- Protonilus MensaeProtonilus MensaeProtonilus Mensae is an area of Mars in the Ismenius Lacus quadrangle. It is centered on the coordinates of 43.86° N and 49.4° E. Its western and eastern longitudes are 37° E and 59.7° E. North and south latitudes are 47.06° N and 39.87° N. Protonilus Mensae is between Deuteronilus Mensae and...
- Martian dichotomyMartian dichotomyThe most conspicuous feature of Martian surface geology is a sharp contrast, known as the Martian dichotomy, between the rugged southern highlands and the relatively smooth northern basins. The two hemispheres differ in elevation by 1 to 3 km...
- Ismenius Lacus quadrangleIsmenius Lacus quadrangleThe Ismenius Lacus quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey Astrogeology Research Program. The quadrangle is located in the northwestern portion of Mars’ eastern hemisphere and covers 0° to 60° east longitude and 30° to 65° north...
- GlacierGlacierA glacier is a large persistent body of ice that forms where the accumulation of snow exceeds its ablation over many years, often centuries. At least 0.1 km² in area and 50 m thick, but often much larger, a glacier slowly deforms and flows due to stresses induced by its weight...
- Nilosyrtis MensaeNilosyrtis MensaeNilosyrtis Mensae is an area of Mars in the Casius quadrangle. It is centered on the coodinates of 36.87° N and 67.9° E. Its western and eastern longitudes are 51.1° E and 74.4° E. North and south latitudes are 36.87° N and 29.61° N. Nilosyrtis Mensae is just to the east of Protonilus Mensae...
- Glaciers on MarsGlaciers on MarsGlaciers formed much of the observable surface in large areas of Mars. Most of the area in high latitudes, especially the Ismenius Lacus quadrangle, is believed to still contain enormous amounts of water ice. Recent evidence has led many planetary scientists to believe that water ice still exists...
External links
- Breathtaking views of Deuteronilus Mensae on Mars from Mars ExpressMars ExpressMars Express is a space exploration mission being conducted by the European Space Agency . The Mars Express mission is exploring the planet Mars, and is the first planetary mission attempted by the agency. "Express" originally referred to the speed and efficiency with which the spacecraft was...
- Scarps in Deuteronilus Mensae from HiRISEHiRISEHigh Resolution Imaging Science Experiment is a camera on board the Mars Reconnaissance Orbiter. The 65 kg , $40 million instrument was built under the direction of the University of Arizona's Lunar and Planetary Laboratory by Ball Aerospace & Technologies Corp....