The Miniature

Thermal Emission Spectrometer The Thermal Emission Spectrometer (TES) is an instrument on board Mars Global Surveyor. TES collects two types of data, hyperspectral thermal infrared data from 6 to 50 micrometres (μm) and bolometric visible-NIR (0.3 to 2.9 μm) measurements. TE ...

(Mini-TES) is an

infrared Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from around ...

spectrometer A spectrometer () is a scientific instrument used to separate and measure spectral components of a physical phenomenon. Spectrometer is a broad term often used to describe instruments that measure a continuous variable of a phenomenon where the ...

used for detecting the composition of a material (typically rocks) from a distance. By making its measurements in the

thermal infrared Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from around ...

part of the

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 from ...

, it has the ability to penetrate through the dust coatings common to the Martian surface which is usually problematic for remote sensing observations. There is one on each of the two

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

Development

The Mini-TES was originally developed by

Raytheon Raytheon Technologies Corporation is an American multinational aerospace and defense conglomerate headquartered in Arlington, Virginia. It is one of the largest aerospace and defense manufacturers in the world by revenue and market capitaliza ...

for the Department of Geological Sciences at

Arizona State University Arizona State University (Arizona State or ASU) is a public research university in the Phoenix metropolitan area. Founded in 1885 by the 13th Arizona Territorial Legislature, ASU is one of the largest public universities by enrollment in the ...

. The Mini-TES is a miniaturized version of Raytheon's

Mars Global Surveyor ''Mars Global Surveyor'' (MGS) was an American robotic space probe developed by NASA's Jet Propulsion Laboratory and launched November 1996. MGS was a global mapping mission that examined the entire planet, from the ionosphere down through the a ...

(MGS) TES, built by Arizona State University and Raytheon SAS’ Santa Barbara Remote Sensing. The MGS TES data helped scientists choose landing sites for the Spirit and Opportunity Mars explorer rovers.

Martian soil

The Mini-TES is used for identifying promising rocks and soils for closer examination, and to determine the processes that formed Martian rocks. It measures the infrared radiation that the target rock or object emits in 167 different wavelengths, providing information about the target's composition. One particular goal is to search for minerals that were formed by the action of water, such as carbonates and clays. The instrument can also look skyward to provide temperature profiles of the Martian atmosphere and detect the abundance of dust and water vapor. The instrument is located inside the warm electronics box in the body of the rover - the mirror redirects radiation into the aperture from above. The Mini-TES instruments aboard the MERs Opportunity and Spirit were never expected to survive the cold Martian winter even if the rovers themselves survived. It was thought that a small

potassium bromide Potassium bromide ( K Br) is a salt, widely used as an anticonvulsant and a sedative in the late 19th and early 20th centuries, with over-the-counter use extending to 1975 in the US. Its action is due to the bromide ion (sodium bromide is equall ...

(KBr)

beamsplitter A beam splitter or ''beamsplitter'' is an optical device that splits a beam of light into a transmitted and a reflected beam. It is a crucial part of many optical experimental and measurement systems, such as interferometers, also finding wide ...

which was housed in an aluminium fitting would crack due to the mismatched

coefficient of thermal expansion Thermal expansion is the tendency of matter to change its shape A shape or figure is a graphics, graphical representation of an object or its external boundary, outline, or external Surface (mathematics), surface, as opposed to other pro ...

. This never happened however and the miniTES instrument on both rovers has survived several Martian winters, and the Spirit rover continues to periodically use the Mini-TES for remote sensing. (The miniTES on the Opportunity rover is not currently being used because of accumulated dust on the mirror following the 2007 dust storm). There are two other types of spectrometers mounted on the

rover Rover may refer to: People * Constance Rover (1910–2005), English historian * Jolanda de Rover (born 1963), Dutch swimmer * Rover Thomas (c. 1920–1998), Indigenous Australian artist Places * Rover, Arkansas, US * Rover, Missouri, US * ...

's arm which provide additional information about the composition when the rover is close enough to touch the object. Mini-Tes can work with

Pancam Each Pancam is one of two electronic stereo cameras on Mars Exploration Rovers ''Spirit'' and ''Opportunity''. It has a filter wheel assembly that enables it to view different wavelengths of light and the pair of Pancams are mounted beside two ...

s to analyze surroundings. The Mini-TES weighs 2.1 kg (4.6 lb) of the total 185 kg (408 lb) for the whole rover.

References

External links

NASA JPL web-page stating purpose of Mini-TES

Technical academic publication on Mini-TES for Mars Exploration Rover

{{Mars Mars Exploration Rover mission Spectrometers Spacecraft instruments

Development

Martian soil

See also

References

External links