North Polar Basin (Mars)

Borealis Basin
	The Borealis Basin is the large blue and green region lying north of the equator. Volcanic eruptions on the Tharsis bulge, the higher elevation region on the left of the image, covered over parts of the basin after its formation.
Location	Northern Hemisphere, Mars
Coordinates	67°N208°E / 67°N 208°E

Last updated January 26, 2025

The North Polar Basin, more commonly known as the Borealis Basin, is a large basin in the northern hemisphere of Mars that covers 40% of the planet.^[1]^[2] Some scientists have postulated that the basin formed during the impact of a single, large body roughly 2% of the mass of Mars, having a diameter of about 1,900 km (1,200 miles) early in the history of Mars, around 4.5 billion years ago.^[1]^[3] However, the basin is not currently recognized as an impact basin by the IAU. The basin is one of the flattest areas in the Solar System, and has an elliptical shape.^[1]^[2]

Large regions within the Borealis Basin

Because the Borealis basin covers 40% of the surface of Mars, and much of the Northern Hemisphere, many currently recognized regions of Mars lie within it:^[2]

Borealis Impact

Formation of the Borealis Basin

One possible explanation for the basin's low, flat and relatively crater-free topography is that the basin was formed by a single large impact. Two simulations of a possible impact sketched a profile for the collision: low velocity—6 to 10 km (3.7 to 6.2 mi) per second—oblique angle and a diameter of 1,600–2,700 km (990–1,680 mi).^[3]^[4] Topographical data from Mars Global Surveyor are consistent with the models and also suggest that the elliptical crater has axes of length 10,600 km (6,600 mi) and 8,500 km (5,300 mi), centered on 67°N208°E / 67°N 208°E / 67; 208 , though this has been partially obscured by later volcanic eruptions that created the Tharsis bulge along its rim.^[2] There is evidence for a secondary rim as well.^[2]^[5] This would make the North Polar Basin by far the largest impact crater in the Solar System, approximately four times the diameter of the next largest craters: Utopia Planitia, which is imbedded inside the North Polar Basin, the South Pole–Aitken basin on the Moon, and Hellas Planitia on Mars's southern hemisphere.^[6]

This impact would have resulted in significant crustal melting and a general increase in the rate of crustal formation for a period of 40 million years following the impact.^[7] Such a large impact would have disturbed the mantle, altering the normal convection currents and causing upwellings which further increase the amount of melting at the impact site.^[7] Overall, such an event would actually increase the rate of cooling of the Martian interior.^[7] The lack of magnetic anomalies observed in the northern hemisphere could be explained by such an impact, as the shock waves produced might have demagnetized the crust.^[7]

However, some authors have instead argued that the inverse is more likely to be true, and that rather than the North Polar Basin being an impact basin, the Southern Hemisphere of Mars may have actually the site of the impact instead, and the thickness of the Southern Hemisphere crust was as a result of impact-induced crust production.^[8]

Potential formation of Phobos and Deimos via Borealis impact

The origin of Mars' moons, Phobos and Deimos (pictured right), is unknown and remains controversial. One theory is that the moons are captured asteroids. However, the moons' near circular orbits and low inclination relative to the Martian equator are not in agreement with the capture hypothesis.^[9] The detection of minerals on Phobos similar to those in the Martian lithosphere, and the unusually low density and high porosity of Phobos, such that the moon would not be expected to remain aggregate if dynamically captured, suggest that the moons could have formed via accretion in Martian orbit, similarly to how Earth's Moon formed.^[9]

While estimates of the mass ejected by a large, Borealis-size impact vary, simulations suggest that a body approximately 0.02 Mars masses (~0.002 Earth Masses) in size is capable of producing a sizable debris disk in Martian orbit, on the order of 5×10²⁰ kg, with a significant fraction of the material remaining close to Mars.^[3]^[9] This figure lies within the estimated mass range necessary to form the two moons, as other data suggests that only 1% of the mass of an accretion disk successfully forms moons.^[9] There are several other large impact basins on Mars that could have ejected enough debris to form the moons.^[9]

Ancient tsunamis

Lomonosov crater, the most likely candidate for the impact that produced the tsunami. It is 150 km in diameter, and is a prominent feature of the Borealis basin. MarsLomonosovCraterWinter.jpg — Lomonosov crater, the most likely candidate for the impact that produced the tsunami. It is 150 km in diameter, and is a prominent feature of the Borealis basin.

Analysis of Mars Global Surveyor data found mineral deposits similar to terminal moraines on Earth along the southern rim of the northern lowlands. Scientists have developed several theories to explain their presence, including: volcanic activity, glacial activity, and a series of Martian tsunamis.^[10] The arrangement of the deposits resembles deposits observed in recent tsunami events on Earth, and other features of the deposits are inconsistent with the volcanic and glacial hypotheses.^[10] One recent investigation identified three impact craters in Acidalia Planitia as being the likely source of the hypothetical tsunamis, with the Lomonosov crater (pictured right) being the most likely candidate.^[10] Here, the tsunami generated by the impactor would have reached heights of 75 m (250 ft), and traveled 150 km (90 mi) past the southern rim.^[10] Dating techniques put the origin of the deposits sometime between the Late Hesperian and Early Amazonian periods, some 3 billion years ago, providing evidence to the presence of an ocean during this period.^[10]

Related Research Articles

Utopia Planitia is a large plain within Utopia, the largest recognized impact basin on Mars and in the Solar System with an estimated diameter of 3,300 km (2,100 mi). It is the Martian region where the Viking 2 lander touched down and began exploring on September 3, 1976, and the Zhurong rover touched down on May 14, 2021, as a part of the Tianwen-1 mission. It is located at the antipode of Argyre Planitia, centered at 46.7°N 117.5°E. It is also in the Casius quadrangle, Amenthes quadrangle, and the Cebrenia quadrangle of Mars. The region is in the broader North Polar/Borealis Basin that covers most of the Northern Hemisphere of Mars.

Areography, also known as the geography of Mars, is a subfield of planetary science that entails the delineation and characterization of regions on Mars. Areography is mainly focused on what is called physical geography on Earth; that is the distribution of physical features across Mars and their cartographic representations. In April 2023, The New York Times reported an updated global map of Mars based on images from the Hope spacecraft. A related, but much more detailed, global Mars map was released by NASA on 16 April 2023.

Hellas Planitia is a plain located within the huge, roughly circular impact basin Hellas located in the southern hemisphere of the planet Mars. Hellas is the fourth- or fifth-largest known impact crater in the Solar System. The basin floor is about 7,152 m (23,465 ft) deep, 3,000 m (9,800 ft) deeper than the Moon's South Pole-Aitken basin, and extends about 2,300 km (1,400 mi) east to west. It is centered at 42.4°S 70.5°E. It features the lowest point on Mars, serves as a known source of global dust storms, and may have contained lakes and glaciers. Hellas Planitia spans the boundary between the Hellas quadrangle and the Noachis quadrangle.

Vastitas Borealis is the largest lowland region of Mars. It is in the northerly latitudes of the planet and encircles the northern polar region. Vastitas Borealis is often simply referred to as the northern plains, northern lowlands or the North polar erg of Mars. The plains lie 4–5 km below the mean radius of the planet, and is centered at 87.73°N 32.53°E. A small part of Vastitas Borealis reaches below 65°N.

Acidalia Planitia is a plain on Mars, between the Tharsis volcanic province and Arabia Terra to the north of Valles Marineris, centered at 49.8°N 339.3°E. Most of this region is found in the Mare Acidalium quadrangle, but a small part is in the Ismenius Lacus quadrangle. The plain contains the famous Cydonia region at the contact with the heavily cratered highland terrain.

The 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 analogous to the field of terrestrial geology. In planetary science, the term geology is used in its broadest sense to mean the study of the solid parts of planets and moons. The term incorporates aspects of geophysics, geochemistry, mineralogy, geodesy, and cartography. A neologism, areology, from the Greek word Arēs (Mars), sometimes appears as a synonym for Mars's geology in the popular media and works of science fiction. The term areology is also used by the Areological Society.

The Borealis quadrangle is a quadrangle on Mercury surrounding the north pole down to 65° latitude. It was mapped in its entirety by the MESSENGER spacecraft, which orbited the planet from 2008 to 2015, excluding areas of permanent shadow near the north pole. Only approximately 25% of the quadrangle was imaged by the Mariner 10 spacecraft during its flybys in 1974 and 1975. The quadrangle is now called H-1.

Mars is the fourth planet from the Sun. The surface of Mars is orange-red because it is covered in iron(III) oxide dust, giving it the nickname "the Red Planet". Mars is among the brightest objects in Earth's sky, and its high-contrast albedo features have made it a common subject for telescope viewing. It is classified as a terrestrial planet and is the second smallest of the Solar System's planets with a diameter of 6,779 km (4,212 mi). In terms of orbital motion, a Martian solar day (sol) is equal to 24.6 hours, and a Martian solar year is equal to 1.88 Earth years. Mars has two natural satellites that are small and irregular in shape: Phobos and Deimos.

The most conspicuous feature of Mars is a sharp contrast, known as the Martian dichotomy, between the Southern and the Northern hemispheres. The two hemispheres' geography differ in elevation by 1 to 3 km. The average thickness of the Martian crust is 45 km, with 32 km in the northern lowlands region, and 58 km in the southern highlands.

<span class="mw-page-title-main">Mars ocean theory</span> Astronomical theory

The Mars ocean theory states that nearly a third of the surface of Mars was covered by an ocean of liquid water early in the planet's geologic history. This primordial ocean, dubbed Paleo-Ocean or Oceanus Borealis, would have filled the basin Vastitas Borealis in the northern hemisphere, a region that lies 4–5 km below the mean planetary elevation, at a time period of approximately 4.1–3.8 billion years ago. Evidence for this ocean includes geographic features resembling ancient shorelines, and the chemical properties of the Martian soil and atmosphere. Early Mars would have required a denser atmosphere and warmer climate to allow liquid water to remain at the surface.

<span class="mw-page-title-main">Ismenius Lacus quadrangle</span> Map of Mars

The Ismenius Lacus quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) 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 latitude. The quadrangle uses a Lambert conformal conic projection at a nominal scale of 1:5,000,000 (1:5M). The Ismenius Lacus quadrangle is also referred to as MC-5. The southern and northern borders of the Ismenius Lacus quadrangle are approximately 3,065 km (1,905 mi) and 1,500 km (930 mi) wide, respectively. The north-to-south distance is about 2,050 km (1,270 mi). The quadrangle covers an approximate area of 4.9 million square km, or a little over 3% of Mars' surface area. The Ismenius Lacus quadrangle contains parts of Acidalia Planitia, Arabia Terra, Vastitas Borealis, and Terra Sabaea.

<span class="mw-page-title-main">Diacria quadrangle</span> Map of Mars

The Diacria quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. The quadrangle is located in the northwestern portion of Mars' western hemisphere and covers 180° to 240° east longitude and 30° to 65° north latitude. The quadrangle uses a Lambert conformal conic projection at a nominal scale of 1:5,000,000 (1:5M). The Diacria quadrangle is also referred to as MC-2. The Diacria quadrangle covers parts of Arcadia Planitia and Amazonis Planitia.

<span class="mw-page-title-main">Hellas quadrangle</span> Map of Mars

The Hellas quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. The Hellas quadrangle is also referred to as MC-28 . The Hellas quadrangle covers the area from 240° to 300° west longitude and 30° to 65° south latitude on the planet Mars. Within the Hellas quadrangle lies the classic features Hellas Planitia and Promethei Terra. Many interesting and mysterious features have been discovered in the Hellas quadrangle, including the giant river valleys Dao Vallis, Niger Vallis, Harmakhis, and Reull Vallis—all of which may have contributed water to a lake in the Hellas basin in the distant past. Many places in the Hellas quadrangle show signs of ice in the ground, especially places with glacier-like flow features.

<span class="mw-page-title-main">Phaethontis quadrangle</span> Map of Mars

The Phaethontis quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. The Phaethontis quadrangle is also referred to as MC-24.

The Noachian is a geologic system and early time period on the planet Mars characterized by high rates of meteorite and asteroid impacts and the possible presence of abundant surface water. The absolute age of the Noachian period is uncertain but probably corresponds to the lunar Pre-Nectarian to Early Imbrian periods of 4100 to 3700 million years ago, during the interval known as the Late Heavy Bombardment. Many of the large impact basins on the Moon and Mars formed at this time. The Noachian Period is roughly equivalent to the Earth's Hadean and early Archean eons when Earth's first life forms likely arose.

The geological history of Mars follows the physical evolution of Mars as substantiated by observations, indirect and direct measurements, and various inference techniques. Methods dating back to 17th-century techniques developed by Nicholas Steno, including the so-called law of superposition and stratigraphy, used to estimate the geological histories of Earth and the Moon, are being actively applied to the data available from several Martian observational and measurement resources. These include landers, orbiting platforms, Earth-based observations, and Martian meteorites.

<span class="mw-page-title-main">LARLE crater</span> Class of Martian impact craters

A low-aspect-ratio layered ejecta crater is a class of impact crater found on the planet Mars. This class of impact craters was discovered by Northern Arizona University scientist Professor Nadine Barlow and Dr. Joseph Boyce from the University of Hawaii in October 2013. Barlow described this class of craters as having a "thin-layered outer deposit" surpassing "the typical range of ejecta". "The combination helps vaporize the materials and create a base flow surge. The low aspect ratio refers to how thin the deposits are relative to the area they cover", Barlow said. The scientists used data from continuing reconnaissance of Mars using the old Mars Odyssey orbiter and the Mars Reconnaissance Orbiter. They discovered 139 LARLE craters ranging in diameter from 1.0 to 12.2 km, with 97% of the LARLE craters found poleward of 35N and 40S. The remaining 3% mainly traced in the equatorial Medusae Fossae Formation.

In summer 1965, the first close-up images from Mars showed a cratered desert with no signs of water. However, over the decades, as more parts of the planet were imaged with better cameras on more sophisticated satellites, Mars showed evidence of past river valleys, lakes and present ice in glaciers and in the ground. It was discovered that the climate of Mars displays huge changes over geologic time because its axis is not stabilized by a large moon, as Earth's is. Also, some researchers maintain that surface liquid water could have existed for periods of time due to geothermal effects, chemical composition, or asteroid impacts. This article describes some of the places that could have held large lakes.

<span class="mw-page-title-main">Tectonics of Mars</span>

Like the Earth, the crustal properties and structure of the surface of Mars are thought to have evolved through time; in other words, as on Earth, tectonic processes have shaped the planet. However, both the ways this change has happened and the properties of the planet's lithosphere are very different when compared to the Earth. Today, Mars is believed to be largely tectonically inactive. However, observational evidence and its interpretation suggests that this was not the case further back in Mars's geological history.

Siton Undae is one of the largest and densest dune fields in the vicinity of Planum Boreum, the Martian northern polar ice-cap. It is named after one of the classical albedo features on Mars. Its name was officially approved by IAU on 20 March 2007. It extends from latitude 73.79°N to 77.5°N and from longitude 291.38°E to 301.4°E. Its centre is located at latitude 75.55°N, longitude 297.28E (62.72°W), and has a diameter of 222.97 kilometres (138.55 mi).

References

Martel, L.M.V. (June, 2001), "Outflow Channels May Make a Case for a Bygone Ocean on Mars", Planetary Science Research Discoveries. (retrieved 17 August 2005)

1 2 3 "NASA - NASA Spacecraft Reveal Largest Crater in Solar System". www.nasa.gov. Retrieved 2017-04-06.
1 2 3 4 5 Andrews-Hanna; et al. (2008). "The Borealis basin and the origin of the Martian crustal dichotomy". Nature . 453 (7199): 1212–1215. Bibcode:2008Natur.453.1212A. doi:10.1038/nature07011. PMID 18580944. S2CID 1981671.
1 2 3 Marinova; et al. (2008). "Mega-impact formation of the Mars hemispheric dichotomy". Nature . 453 (7199): 1216–1219. Bibcode:2008Natur.453.1216M. doi:10.1038/nature07070. PMID 18580945. S2CID 4328610.
↑ Nimmo; et al. (2008). "Implications of an impact origin for the Martian hemispheric dichotomy". Nature . 453 (7199): 1220–1223. Bibcode:2008Natur.453.1220N. doi:10.1038/nature07025. PMID 18580946. S2CID 4402065.
↑ "Huge Impact Created Mars' Split Personality". Space.com . Retrieved 2008-07-01.
↑ Chandler, David (2008-06-25). "Solar system's biggest impact scar discovered: MIT scientists solve riddle of Mars' two-faced nature". MIT News. Retrieved 2015-01-01.
1 2 3 4 Ghods, Abdolreza; Arkani-Hamed, Jafar (2011-09-01). "Effects of the Borealis impact on the mantle dynamics of Mars". Physics of the Earth and Planetary Interiors. 188 (1–2): 37–46. Bibcode:2011PEPI..188...37G. doi:10.1016/j.pepi.2011.06.010.
↑ Ballantyne, Harry A.; Jutzi, Martin; Golabek, Gregor J.; Mishra, Lokesh; Cheng, Kar Wai; Rozel, Antoine B.; Tackley, Paul J. (March 2023). "Investigating the feasibility of an impact-induced Martian Dichotomy". Icarus. 392: 115395. arXiv: 2212.02466 . doi:10.1016/j.icarus.2022.115395.
1 2 3 4 5 Citron, Robert I.; Genda, Hidenori; Ida, Shigeru (2015-05-15). "Formation of Phobos and Deimos via a giant impact". Icarus. 252: 334–338. arXiv: 1503.05623 . Bibcode:2015Icar..252..334C. doi:10.1016/j.icarus.2015.02.011. S2CID 17089080.
1 2 3 4 5 Costard, Francois; Séjourné, Antoine; Kelfoun, Karim; Clifford, Stephen; Lavigne, Franck; Di Pietro, Ilaria; Bouley, Sylvain (2017-01-01). "Modeling tsunami propagation and the emplacement of thumbprint terrain in an early Mars ocean" (PDF). Journal of Geophysical Research: Planets. 122 (3): 2016JE005230. Bibcode:2017JGRE..122..633C. doi:10.1002/2016JE005230. ISSN 2169-9100. S2CID 132378050.

This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.

[:5-1] 1 2 3 "NASA - NASA Spacecraft Reveal Largest Crater in Solar System". www.nasa.gov. Retrieved 2017-04-06.

[:3-2] 1 2 3 4 5 Andrews-Hanna; et al. (2008). "The Borealis basin and the origin of the Martian crustal dichotomy". Nature . 453 (7199): 1212–1215. Bibcode:2008Natur.453.1212A. doi:10.1038/nature07011. PMID 18580944. S2CID 1981671.

[:6-3] 1 2 3 Marinova; et al. (2008). "Mega-impact formation of the Mars hemispheric dichotomy". Nature . 453 (7199): 1216–1219. Bibcode:2008Natur.453.1216M. doi:10.1038/nature07070. PMID 18580945. S2CID 4328610.

[4] Nimmo; et al. (2008). "Implications of an impact origin for the Martian hemispheric dichotomy". Nature . 453 (7199): 1220–1223. Bibcode:2008Natur.453.1220N. doi:10.1038/nature07025. PMID 18580946. S2CID 4402065.

[5] "Huge Impact Created Mars' Split Personality". Space.com . Retrieved 2008-07-01.

[6] Chandler, David (2008-06-25). "Solar system's biggest impact scar discovered: MIT scientists solve riddle of Mars' two-faced nature". MIT News. Retrieved 2015-01-01.

[:4-7] 1 2 3 4 Ghods, Abdolreza; Arkani-Hamed, Jafar (2011-09-01). "Effects of the Borealis impact on the mantle dynamics of Mars". Physics of the Earth and Planetary Interiors. 188 (1–2): 37–46. Bibcode:2011PEPI..188...37G. doi:10.1016/j.pepi.2011.06.010.

[8] Ballantyne, Harry A.; Jutzi, Martin; Golabek, Gregor J.; Mishra, Lokesh; Cheng, Kar Wai; Rozel, Antoine B.; Tackley, Paul J. (March 2023). "Investigating the feasibility of an impact-induced Martian Dichotomy". Icarus. 392: 115395. arXiv: 2212.02466 . doi:10.1016/j.icarus.2022.115395.

[:2-9] 1 2 3 4 5 Citron, Robert I.; Genda, Hidenori; Ida, Shigeru (2015-05-15). "Formation of Phobos and Deimos via a giant impact". Icarus. 252: 334–338. arXiv: 1503.05623 . Bibcode:2015Icar..252..334C. doi:10.1016/j.icarus.2015.02.011. S2CID 17089080.

[:0-10] 1 2 3 4 5 Costard, Francois; Séjourné, Antoine; Kelfoun, Karim; Clifford, Stephen; Lavigne, Franck; Di Pietro, Ilaria; Bouley, Sylvain (2017-01-01). "Modeling tsunami propagation and the emplacement of thumbprint terrain in an early Mars ocean" (PDF). Journal of Geophysical Research: Planets. 122 (3): 2016JE005230. Bibcode:2017JGRE..122..633C. doi:10.1002/2016JE005230. ISSN 2169-9100. S2CID 132378050.

[1]

[2]

[3]

[4]

[5]

[6]

[7]

[8]

[9]

[10]