Product Code Database
Arsia Mons is the southernmost of three volcanoes (collectively known as Tharsis Montes) 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 volcano in the Solar System, Olympus Mons, is to its northwest. Its name comes from a corresponding albedo feature on a map by Giovanni Schiaparelli, which he named in turn after the legendary Roman forest of Silva Arsia. Historically, it was known as Nodus Gordii ("Gordian knot") before being renamed.
The volcano is in diameter, almost high (more than higher than the surrounding plains Catalog Page for PIA02337), and the summit caldera is 110 km (72 miles) wide. Catalog Page for PIA03948 It experiences atmospheric pressure lower than 107 pascals Martian Weather Observation NASA MGS data 9.2 degrees S 238.2 degrees E 17757 meters 1.07 mbar at the summit. Excluding Olympus Mons, it is the largest known volcano in terms of volume. Arsia Mons has 30 times the volume of Mauna Loa in Hawaii, the largest volcano on the Earth. (2008). 9780521852265 ISBN 9780521852265
The caldera of Arsia Mons was formed when the mountain collapsed in on itself after its reservoir of magma was exhausted. There are many other geologic collapse features on the mountain's flanks. Catalog Page for PIA03799 The caldera floor formed around 150 Mya ago.
The shield is transected roughly northeast to southwest by a set of collapse features. The collapse features on the shield are connected by a line of small shield volcanoes on the floor of the caldera. It is possible that this line represents a significant fault similar to others found on the Tharsis bulge. This fault may represent the source of the Arsia lavas.
The rift area to the southwest has been imaged in significant detail by the European Space Agency probe Mars Express. In 2004, a 3D map of this region was created at high resolution. Cliffs, landslides, and numerous collapse features can be seen in this detailed image. Combined with the extensive lava flows at the termination of the rift, this may reveal areas that drained the caldera lavas and contributed to the collapse.
The northwest flank of the volcano is significantly different and rougher than the southeast flank, and the features may represent evidence of glaciers.
A study using a global climate model found that the Medusae Fossae Formation could have been formed from ancient volcanic ash from Apollinaris Mons, Arsia Mons, and possibly Pavonis Mons.
From day to night, temperatures of the circular features change only about one-third as much as the change in temperature of surrounding ground. While this is more variable than large caves on Earth, it is consistent with there being deep pits. However, due to the extreme altitude, it is unlikely that they will be able to harbour any form of Martian life.
A more recent photograph of one of the features shows sunlight illuminating a side wall, suggesting that it may simply be a vertical pit rather than an entrance to a larger underground space. Nonetheless, the darkness of this feature implies that it must be at least 178 meters deep.
File:Arsia Mons THEMIS day IR 100m v11.5 0.5.jpg|Arsia Mons and its surroundings in a THEMIS daytime infrared image mosaic. A huge fan-shaped expanse of knobby deposits (the Arsia Sulci), believed left by past glaciation, extends northwestward from the mountain.
File:PIA13540 - Layers in Martian volcano Arsia Mons.jpg|Layers from numerous lava flows are exposed on the side of a pit on the lower west flank of Arsia Mons (photo by HiRISE).
File:Mars; Arsia Mons cave entrance -MRO.jpg|Possible cave entrance ("Jeanne") on Arsia Mons
|
|
