The Dynamic Albedo of Neutrons (DAN) instrument is an experiment mounted on the

Mars Science Laboratory Mars Science Laboratory (MSL) is a robotic space probe mission to Mars launched by NASA on November 26, 2011, which successfully landed ''Curiosity'', a Mars rover, in Gale Crater on August 6, 2012. The overall objectives include investigati ...

''Curiosity'' rover. It is a pulsed sealed-tube

neutron source A neutron source is any device that emits neutrons, irrespective of the mechanism used to produce the neutrons. Neutron sources are used in physics, engineering, medicine, nuclear weapons, petroleum exploration, biology, chemistry, and nuclear p ...

and detector used to measure

hydrogen Hydrogen is the chemical element with the symbol H and atomic number 1. Hydrogen is the lightest element. At standard conditions hydrogen is a gas of diatomic molecules having the formula . It is colorless, odorless, tasteless, non-toxic, an ...

ice Ice is water frozen into a solid state, typically forming at or below temperatures of 0 degrees Celsius or Depending on the presence of impurities such as particles of soil or bubbles of air, it can appear transparent or a more or less opaqu ...

and

water Water (chemical formula ) is an inorganic, transparent, tasteless, odorless, and nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living organisms (in which it acts as a ...

at or near the

Martian surface The study of surface characteristics (or surface properties and processes) 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 ...

. The instrument consists of the detector element (DE) and a 14.1 MeV pulsing neutron generator (PNG). The die-away time of neutrons is measured by the DE after each neutron pulse from the PNG. DAN was provided by the

Russian Federal Space Agency The State Space Corporation "Roscosmos" (russian: Государственная корпорация по космической деятельности «Роскосмос»), commonly known simply as Roscosmos (russian: Роскосмос) ...

, funded by

Russia Russia (, , ), or the Russian Federation, is a List of transcontinental countries, transcontinental country spanning Eastern Europe and North Asia, Northern Asia. It is the List of countries and dependencies by area, largest country in the ...

and is under the leadership of Principal Investigator Igor Mitrofanov.

History

On August 18, 2012 (sol ), DAN was turned on, marking the success of a Russian-American collaboration on the surface of Mars and the first working Russian science instrument on the Martian surface since

Mars 3 Mars 3 was a robotic space probe of the Soviet Mars program, launched May 28, 1971, nine days after its twin spacecraft Mars 2. The probes were identical robotic spacecraft launched by Proton-K rockets with a Blok D upper stage, each consisting ...

stopped transmitting over forty years ago.NSSDC – Mars 3
/ref> The instrument is designed to detect subsurface water. On March 18, 2013 (sol ), NASA reported evidence of

mineral hydration In chemistry, mineral hydration is an inorganic chemical reaction which adds water to the crystal structure of a mineral, usually creating a new mineral, usually called a '' hydrate''. In geological terms, the process of mineral hydration is kn ...

, likely hydrated

calcium sulfate Calcium sulfate (or calcium sulphate) is the inorganic compound with the formula CaSO4 and related hydrates. In the form of γ-anhydrite (the anhydrous form), it is used as a desiccant. One particular hydrate is better known as plaster of Pari ...

, in several rock samples including the broken fragments of "Tintina" rock and "Sutton Inlier" rock as well as in

veins Veins are blood vessels in humans and most other animals that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are the pulmonary and umbilical veins, both of which carry oxygenated b ...

and nodules in other rocks like "Knorr" rock and "Wernicke" rock. Analysis using the rover's DAN instrument provided evidence of subsurface water, amounting to as much as 4% water content, down to a depth of , in the rover's traverse from the

Bradbury Landing Bradbury Landing is the August 6, 2012, landing site within Gale crater on planet Mars of the Mars Science Laboratory (MSL) ''Curiosity'' rover. On August 22, 2012, on what would have been his 92nd birthday, NASA named the site for author Ra ...

site to the

Yellowknife Bay Yellowknife (; Dogrib: ) is the capital, largest community, and only city in the Northwest Territories, Canada. It is on the northern shore of Great Slave Lake, about south of the Arctic Circle, on the west side of Yellowknife Bay near the o ...

area in the Glenelg terrain. PIA17762-MarsCuriosityRover-DAN-2M-Pulses-20140129

On August 19, 2015, NASA scientists reported that the DAN instrument on ''Curiosity'' detected an unusual hydrogen-rich area, at "Marias Pass," on Mars. The hydrogen found seemed related to water or

hydroxyl In chemistry, a hydroxy or hydroxyl group is a functional group with the chemical formula and composed of one oxygen atom covalently bonded to one hydrogen atom. In organic chemistry, alcohols and carboxylic acids contain one or more hydroxy ...

ions in rocks within three feet beneath the rover, according to the scientists. PIA19809-MarsCuriosityRover-HydrogenRichAreaFound-20150721

References

External links

* {{Portal bar, Solar System Mars Science Laboratory instruments Space program of Russia Space science experiments Spacecraft instruments

History

See also

References

External links