Pavonis Mons
Encyclopedia
Pavonis Mons is a large shield volcano
located in the Tharsis
region of the planet Mars
. It is the middle member of a chain of three volcanic mountains (collectively known as the Tharsis Montes
) that straddle the Martian equator between longitudes 235°E and 259°E. The volcano was discovered by the Mariner 9
spacecraft in 1971 and was originally called Middle Spot. Its name formally became Pavonis Mons in 1973. Pavonis Mons is Latin for "Peacock Mountain."
- approximately 400 km southwest of Ascraeus Mons
(the northernmost of the Tharsis Montes) and 400 km northeast of Arsia Mons
(the southernmost member of the chain). The Tharsis Montes volcanoes lie along the crest of a northeast-trending rise (Tharsis buldge) that extends more than 3,000 km across the western equatorial region of Mars. Olympus Mons
, the largest volcano in the Solar System
lies at the edge of the Tharsis buldge, about 1,200 km northwest of Pavonis Mons.
Pavonis Mons is the smallest of the Tharsis Montes volcanoes, measuring about 375 km across and standing 14 km above Mars' mean surface level. As a shield volcano
, Pavonis Mons has an extremely low profile with flank slopes that average only 4°. The summit contains a deep, circular caldera
that is 47 km in diameter and almost 5 km deep. A larger, shallower depression lies immediately northeast of the smaller caldera. The large depression is about 90 km in diameter and structurally more complex than the small caldera.
Like most of the Tharsis region, Pavonis Mons has a high albedo
(reflectivity) and low thermal inertia, indicating that the volcano and surrounding areas are covered with large amounts of fine dust (see Martian surface
). The dust forms a mantle over the surface that obscures or mutes much of the fine-scale topography and geology of the region. Tharsis is probably dusty because of its high elevations. The summit experiences an atmospheric pressure of around 130 Pa
(1.3 mbar), about 21% of Mars' mean surface pressure. The atmospheric density is too low to mobilize and remove dust once it is deposited.
and Odyssey
data, combined with developments in the study of glaciers, scientists suggest that glaciers once existed on Pavonis Mons and probably still do to some extent. Evidence for this includes concentric ridges (moraines "dropped" by glaciers), a knobby area (caused by ice sublimating), and a smooth section that flows over other deposits (debris-covered glacial ice). The ice could have been deposited when the tilt of Mars changed the climate, thereby causing more moisture to be present in the atmosphere. Studies suggest the glaciation happened in the Late Amazonian period, the most recent period in Mars chronology. Multiple stages of glaciation probably occurred. The ice present today represents one more resource for possible future colonization of the planet.
Shield volcano
A shield volcano is a type of volcano usually built almost entirely of fluid lava flows. They are named for their large size and low profile, resembling a warrior's shield. This is caused by the highly fluid lava they erupt, which travels farther than lava erupted from more explosive volcanoes...
located in the Tharsis
Tharsis
The Tharsis region on Mars is a vast volcanic plateau centered near the equator in Mars’ western hemisphere. The region is home to the largest volcanoes in the Solar System, including the three enormous shield volcanoes Arsia Mons, Pavonis Mons, and Ascraeus Mons, which are collectively known as...
region of the planet Mars
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...
. It is the middle member of a chain of three volcanic mountains (collectively known as the Tharsis Montes
Tharsis Montes
The Tharsis Montes are three large shield volcanoes in the Tharsis region of the planet Mars. From north to south, the volcanoes are Ascraeus Mons, Pavonis Mons and Arsia Mons. Mons is the Latin word for mountain...
) that straddle the Martian equator between longitudes 235°E and 259°E. The volcano was discovered by the Mariner 9
Mariner 9
Mariner 9 was a NASA space orbiter that helped in the exploration of Mars and was part of the Mariner program. Mariner 9 was launched toward Mars on May 30, 1971 from Cape Canaveral Air Force Station and reached the planet on November 13 of the same year, becoming the first spacecraft to orbit...
spacecraft in 1971 and was originally called Middle Spot. Its name formally became Pavonis Mons in 1973. Pavonis Mons is Latin for "Peacock Mountain."
General Description
Pavonis Mons stands at the southern edge of the Tharsis quadrangleTharsis quadrangle
The Tharsis quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey Astrogeology Research Program. The Tharsis quadrangle is also referred to as MC-9 ....
- approximately 400 km southwest of Ascraeus Mons
Ascraeus Mons
Ascraeus Mons is a large shield volcano located in the Tharsis region of the planet Mars. It is the northernmost and tallest of three shield volcanoes collectively known as the Tharsis Montes. The volcano's location corresponds to the classical albedo feature Ascraeus Lacus.Ascraeus Mons was...
(the northernmost of the Tharsis Montes) and 400 km northeast of Arsia Mons
Arsia Mons
Arsia Mons is the southernmost of three volcanos on the Tharsis bulge near the equator of the planet Mars. To its north is Pavonis Mons, and north of that is Ascraeus Mons. The tallest mountain in the solar system, Olympus Mons, is to its northwest...
(the southernmost member of the chain). The Tharsis Montes volcanoes lie along the crest of a northeast-trending rise (Tharsis buldge) that extends more than 3,000 km across the western equatorial region of Mars. Olympus Mons
Olympus Mons
Olympus Mons is a large volcanic mountain on the planet Mars. At a height of almost , it is one of the tallest mountains in the Solar System, three times as tall as Mount Everest and more than twice the height of Mauna Kea the tallest mountain on Earth. Olympus Mons is the youngest of the large...
, the largest volcano in the Solar System
Solar System
The Solar System consists of the Sun and the astronomical objects gravitationally bound in orbit around it, all of which formed from the collapse of a giant molecular cloud approximately 4.6 billion years ago. The vast majority of the system's mass is in the Sun...
lies at the edge of the Tharsis buldge, about 1,200 km northwest of Pavonis Mons.
Pavonis Mons is the smallest of the Tharsis Montes volcanoes, measuring about 375 km across and standing 14 km above Mars' mean surface level. As a shield volcano
Shield volcano
A shield volcano is a type of volcano usually built almost entirely of fluid lava flows. They are named for their large size and low profile, resembling a warrior's shield. This is caused by the highly fluid lava they erupt, which travels farther than lava erupted from more explosive volcanoes...
, Pavonis Mons has an extremely low profile with flank slopes that average only 4°. The summit contains a deep, circular caldera
Caldera
A caldera is a cauldron-like volcanic feature usually formed by the collapse of land following a volcanic eruption, such as the one at Yellowstone National Park in the US. They are sometimes confused with volcanic craters...
that is 47 km in diameter and almost 5 km deep. A larger, shallower depression lies immediately northeast of the smaller caldera. The large depression is about 90 km in diameter and structurally more complex than the small caldera.
Like most of the Tharsis region, Pavonis Mons has a high albedo
Albedo
Albedo , or reflection coefficient, is the diffuse reflectivity or reflecting power of a surface. It is defined as the ratio of reflected radiation from the surface to incident radiation upon it...
(reflectivity) and low thermal inertia, indicating that the volcano and surrounding areas are covered with large amounts of fine dust (see Martian surface
Martian Surface
The study of surface characteristics is a broad category of Mars science that examines the nature of the materials making up the Martian surface. The study evolved from telescopic and remote-sensing techniques developed by astronomers to study planetary surfaces...
). The dust forms a mantle over the surface that obscures or mutes much of the fine-scale topography and geology of the region. Tharsis is probably dusty because of its high elevations. The summit experiences an atmospheric pressure of around 130 Pa
Pascal (unit)
The pascal is the SI derived unit of pressure, internal pressure, stress, Young's modulus and tensile strength, named after the French mathematician, physicist, inventor, writer, and philosopher Blaise Pascal. It is a measure of force per unit area, defined as one newton per square metre...
(1.3 mbar), about 21% of Mars' mean surface pressure. The atmospheric density is too low to mobilize and remove dust once it is deposited.
Geology
The bulk of the volcano's surface consists of lava flows of early Amazonian age. The northern flanks of the volcano are highly faulted with grabens and normal faults concentric to the volcano's summit caldera. To its lower east flank, there is a chain of elliptical, or oval-shaped, pits, lined up down the center of a shallow trough. They were both formed by collapse associated by faulting – the scarp on each side of the trough is a fault line. (Such features are normally found when the ground is moved by molten rock or tectonic forces.)Glaciers
Using MGSMars 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...
and Odyssey
2001 Mars Odyssey
2001 Mars Odyssey is a robotic spacecraft orbiting the planet Mars. The project was developed by NASA, and contracted out to Lockheed Martin, with an expected cost for the entire mission of US$297 million. Its mission is to use spectrometers and electronic imagers to hunt for evidence of past or...
data, combined with developments in the study of glaciers, scientists suggest that glaciers once existed on Pavonis Mons and probably still do to some extent. Evidence for this includes concentric ridges (moraines "dropped" by glaciers), a knobby area (caused by ice sublimating), and a smooth section that flows over other deposits (debris-covered glacial ice). The ice could have been deposited when the tilt of Mars changed the climate, thereby causing more moisture to be present in the atmosphere. Studies suggest the glaciation happened in the Late Amazonian period, the most recent period in Mars chronology. Multiple stages of glaciation probably occurred. The ice present today represents one more resource for possible future colonization of the planet.
Possible evidence of plate tectonics
Pavonis Mons is the middle of three volcanos (collectively known as Tharsis Montes) on the Tharsis bulge near the equator of the planet Mars. The other Tharsis volcanoes are Ascraeus Mons and Arsia Mons. The three Tharsis Montes, together with some smaller volcanoes to the north, form a fairly straight line. It has been proposed that this straight line of volcanoes is the result of plate motion which on Earth makes chains of "hot spot" volcanoes.Use in popular culture
- Pavonis Mons provides the putative setting for the song "Approaching Pavonis Mons by Balloon (Utopia Planitia)" by The Flaming LipsThe Flaming LipsThe Flaming Lips are an American alternative rock band, formed in Oklahoma City, Oklahoma in 1983.Melodically, their sound contains lush, multi-layered, psychedelic rock arrangements, but lyrically their compositions show elements of space rock, including unusual song and album titles—such as "What...
, released as part of the albumYoshimi Battles the Pink RobotsYoshimi Battles the Pink Robots-Special edition DVD-Audio:-The Flaming Lips:* Wayne Coyne - guitar, vocals, artwork, mixing, production* Michael Ivins - bass guitar, keyboards, vocals, mixing, production, additional engineering...
. - Pavonis Mons is the site of the city of Sheffield in Kim Stanley RobinsonKim Stanley RobinsonKim Stanley Robinson is an American science fiction writer known for his award-winning Mars trilogy. His work delves into ecological and sociological themes regularly, and many of his novels appear to be the direct result of his own scientific fascinations, such as the fifteen years of research...
's Mars TrilogyMars trilogyThe Mars trilogy is a series of award-winning science fiction novels by Kim Stanley Robinson that chronicles the settlement and terraforming of the planet Mars through the intensely personal and detailed viewpoints of a wide variety of characters spanning almost two centuries...
of novels. Sheffield stands at the base of Mars's space elevatorSpace elevatorA space elevator, also known as a geostationary orbital tether or a beanstalk, is a proposed non-rocket spacelaunch structure...
.