Mons Hansteen is a mountain on the

Moon The Moon is Earth's only natural satellite. It Orbit of the Moon, orbits around Earth at Lunar distance, an average distance of (; about 30 times Earth diameter, Earth's diameter). The Moon rotation, rotates, with a rotation period (lunar ...

, also known as Hansteen Alpha (α), named after Christopher Hansteen. It is roughly triangular in shape and occupies an area about 30 km across on the western margin of Oceanus Procellarum, southeast of the crater Hansteen and north of the dark-floored crater Billy. It is thought to be an extrusion of volcanic material that is younger than the crater Hansteen, with most of surface volcanic ash been deposited 3.5-3.74 billion years ago. The Mons Hansteen belongs to rare class of non-mare moon volcanoes.

Composition

The extruded material is significantly enriched in silica, and strongly depleted in iron and titanium oxides compared to surrounding mare terrain. Initially, it was believed its lavas are not as evolved as in Compton–Belkovich Thorium Anomaly, but by 2004 the low thorium enrichment signal was attributed to small size of volcanic complex, making it composition compatible with highly processed silicic lavas. By 2013, a patchy deposits of magnesium

spinel Spinel () is the magnesium/aluminium member of the larger spinel group of minerals. It has the formula in the cubic crystal system. Its name comes from the Latin word , a diminutive form of ''spine,'' in reference to its pointed crystals. Prop ...

were detected in the central and western parts of the volcanic dome. The spinel-rich areas are associated with boulder fields, and fringed by areas showing a sign of hydration, with 4-8% of mineral by weight been hydroxylated. The average bulk density of material in Mons Hansteen is extremely low, been equal only to 1500–2000 kg/m³.The Bulk Density of the Small Lunar Volcanos Gruithuisen Delta and Hansteen Alpha: Implications for Volcano Composition and Petrogenesis
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References

External links

Mons Hansteen: A Window into Lunar Magmatic Processes

Lunar Reconnaissance Orbiter The Lunar Reconnaissance Orbiter (LRO) is a NASA robotic spacecraft currently orbiting the Moon in an eccentric Polar orbit, polar mapping orbit. Data collected by LRO have been described as essential for planning NASA's future human and robotic ...

Camera (LROC) article, Posted by Brett Denevi on April 10, 2017 Hansteen Hansteen Hansteen {{Moon-stub

Composition

See also

References

External links