Adirondack is the nickname for

Mars Exploration Rover NASA's Mars Exploration Rover (MER) mission was a robotic space mission involving two Mars rovers, '' Spirit'' and '' Opportunity'', exploring the planet Mars. It began in 2003 with the launch of the two rovers to explore the Martian surface ...

''Spirit'''s first target rock. Scientists chose Adirondack to be ''Spirit''s first target rock after considering another, called Sashimi, that would have been a shorter, straight-ahead drive. ''Spirit'' traversed the sandy martian terrain at Gusev Crater to arrive in front of this football-sized rock on January 18, 2004, just three days after it successfully rolled off the lander. Scientists named the angular rock after the Adirondack mountain range in New York. The name "Adirondacks" is an Anglicized version of the

Mohawk Mohawk may refer to: Related to Native Americans * Mohawk people, an indigenous people of North America (Canada and New York) *Mohawk language, the language spoken by the Mohawk people * Mohawk hairstyle, from a hairstyle once thought to have been ...

''ratirontaks'', meaning "they eat trees", a derogatory name which the Mohawk historically applied to the Algonquian-speaking tribes of the

Adirondack Mountains The Adirondack Mountains (; a-də-RÄN-dak) form a massif in northeastern New York with boundaries that correspond roughly to those of Adirondack Park. They cover about 5,000 square miles (13,000 km2). The mountains form a roughly circular ...

; when food was scarce, the Algonquians would eat the buds and bark of trees. Rockgusev

The rock was selected as ''Spirit''s first target because its dust-free, flat surface was ideally suited for grinding. Clean surfaces also are better for examining a rock's top coating. ''Spirit'' also returned

microscopic The microscopic scale () is the scale of objects and events smaller than those that can easily be seen by the naked eye, requiring a lens or microscope to see them clearly. In physics, the microscopic scale is sometimes regarded as the scale be ...

images and Mössbauer spectrometer readings of Adirondack taken the day before the rover developed computer and communication problems on January 22, 2004. Both are unprecedented investigations of any rock on another

planet A planet is a large, rounded astronomical body that is neither a star nor its remnant. The best available theory of planet formation is the nebular hypothesis, which posits that an interstellar cloud collapses out of a nebula to create a you ...

. The microscopic images indicate Adirondack is a hard,

crystalline A crystal or crystalline solid is a solid material whose constituents (such as atoms, molecules, or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions. In addition, macros ...

rock. The peaks large and small in Adirondack's

electromagnetic spectrum The electromagnetic spectrum is the range of frequencies (the spectrum) of electromagnetic radiation and their respective wavelengths and photon energies. The electromagnetic spectrum covers electromagnetic waves with frequencies ranging fro ...

reveal that the

minerals In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid chemical compound with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed ...

in the rock include

olivine The mineral olivine () is a magnesium iron silicate with the chemical formula . It is a type of nesosilicate or orthosilicate. The primary component of the Earth's upper mantle, it is a common mineral in Earth's subsurface, but weathers quickl ...

, pyroxene and

magnetite Magnetite is a mineral and one of the main iron ores, with the chemical formula Fe2+Fe3+2O4. It is one of the oxides of iron, and is ferrimagnetic; it is attracted to a magnet and can be magnetized to become a permanent magnet itself. With th ...

- a common composition in volcanic

basalt Basalt (; ) is an aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the surface of a rocky planet or moon. More than 90 ...

rocks on Earth. Adirondack turned out to be typical of the other rocks on the plains. ''Spirit'' rover's instruments determined that Adironack and other rocks of the plains contain the minerals pyroxene,

plagioclase Plagioclase is a series of tectosilicate (framework silicate) minerals within the feldspar group. Rather than referring to a particular mineral with a specific chemical composition, plagioclase is a continuous solid solution series, more pro ...

, and

. These rocks can be classified in different ways. The amounts and types of minerals make the rocks primitive basalts—also called picritic basalts. The rocks are similar to ancient terrestrial rocks called basaltic komatiites. Rocks of the plains also resemble the basaltic

shergottite A Martian meteorite is a rock that formed on Mars, was ejected from the planet by an impact event, and traversed interplanetary space before landing on Earth as a meteorite. , 277 meteorites had been classified as Martian, less than half a percen ...

s, meteorites which came from Mars. One classification system compares the amount of alkali elements to the amount of silica on a graph; in this system, Gusev plains rocks lie near the junction of basalt, picrobasalt, and tephrite. The Irvine-Barager classification calls them basalts. Adirondack has been very slightly altered, probably by thin films of water because they are softer and contain veins of light colored material that may be bromine compounds, as well as coatings or rinds. It is thought that small amounts of water may have gotten into cracks inducing mineralization processes.Arvidson, R. E., et al. (2004) ''Science'', 305, 821-824 Coatings on the rocks in the plains may have occurred when rocks were buried and interacted with thin films of water and dust. One sign that they were altered was that it was easier to grind these rocks compared to the same types of rocks found on Earth.

References

External links

Official Mars Rovers site

{{Portal bar, Solar System Rocks on Mars

See also

References

External links