North Polar Basin (Mars)
Encyclopedia
The North Polar Basin, or Borealis basin, is a large basin in the northern hemisphere of Mars that covers 40% of the planet. Chryse Planitia
, the landing site of the Viking 1
lander, is a bay which opens into this 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 – 10 km/s), oblique angle and diameter 1,600 - 2,700 km. Topographical data from the Mars Global Surveyor
are consistent with the models and also suggest that the elliptical crater has axes of length 10,600 km and 8,500 km, centered on 67°N, 208°E, though this has been partially obscured by later volcanic eruptions that created the Tharsis bulge along its rim. There is evidence for a secondary rim as well. 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, the South Pole – Aitken basin on Earth
's Moon
and Hellas Planitia
on the southern hemisphere of Mars.
Chryse Planitia
Chryse Planitia is a smooth circular plain in the northern equatorial region of Mars close to the Tharsis region to the west, centered at . Chryse Planitia lies partially in the Lunae Palus quadrangle and partially in the Oxia Palus quadrangle...
, the landing site of the Viking 1
Viking 1
Viking 1 was the first of two spacecraft sent to Mars as part of NASA's Viking program. It was the first spacecraft to successfully land on Mars and perform its mission, and until May 19, 2010 held the record for the second longest Mars surface mission of 6 years and 116 days .- Mission :Following...
lander, is a bay which opens into this 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 – 10 km/s), oblique angle and diameter 1,600 - 2,700 km. Topographical data from the Mars Global Surveyor
Mars Global Surveyor
The Mars Global Surveyor was a US spacecraft developed by NASA's Jet Propulsion Laboratory and launched November 1996. It began the United States's return to Mars after a 10-year absence. It completed its primary mission in January 2001 and was in its third extended mission phase when, on 2...
are consistent with the models and also suggest that the elliptical crater has axes of length 10,600 km and 8,500 km, centered on 67°N, 208°E, though this has been partially obscured by later volcanic eruptions that created the Tharsis bulge along its rim. There is evidence for a secondary rim as well. 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, the South Pole – Aitken basin on Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...
's Moon
Moon
The Moon is Earth's only known natural satellite,There are a number of near-Earth asteroids including 3753 Cruithne that are co-orbital with Earth: their orbits bring them close to Earth for periods of time but then alter in the long term . These are quasi-satellites and not true moons. For more...
and Hellas Planitia
Hellas Planitia
Hellas Planitia, also known as the Hellas Impact Basin, is a huge, roughly circular impact basin located in the southern hemisphere of the planet Mars. It is the second or third largest impact crater and the largest visible impact crater known in the Solar System...
on the southern hemisphere of Mars.
See also
- Vastitas BorealisVastitas BorealisVastitas 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 or Northern lowlands of Mars. The plains lie 4–5 km below the mean radius of...
- Mars Ocean HypothesisMars Ocean HypothesisThe Mars Ocean Hypothesis 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....
(Oceanus Borealis) - Utopia PlanitiaUtopia PlanitiaUtopia Planitia is the largest recognized impact basin on Mars with an estimated diameter of 3300 km, and is the Martian region where the Viking 2 lander touched down and began exploring on September 3, 1976. It is located at the antipode of Argyre Planitia, centered at...
- Planum BoreumPlanum BoreumPlanum Boreum is the northern polar plain on Mars. It extends northward from roughly 80°N and is centered at . Surrounding the high polar plain is a flat and featureless lowland plain called Vastitas Borealis which extends for approximately 1500 kilometres southwards, dominating the northern...
- North Polar BasinNorth Polar BasinThe North Polar Basin is an oceanic basin in the Arctic Ocean, consisting of two main parts, the Amerasian Basin and the Eurasian Basin , which are separated by the Lomonosov Ridge, a mid-ocean ridge running between north Greenland and the New Siberian Islands...
(Earth)