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Mars has electrically charged metal atoms high in its atmosphere, according to new data from NASA’s MAVEN spacecraft. This can unveil the previously invisible activity in the mysterious electrically charged ionosphere of the red planet.
Mars Atmosphere and Volatile EvolutioN Mission (MAVEN) is a space probe developed by NASA designed to study the Martian atmosphere while orbiting Mars. Mission goals include determining how the planet’s atmosphere and water, presumed to have once been substantial, were lost over time.
The MAVEN mission has primary scientific objectives:
1.Artist conception of MAVEN spacecraft
2.Determine the role that loss of volatiles to space from the Martian atmosphere has played through time.
3.Determine the current state of the upper atmosphere, ionosphere, and interactions with the solar wind.
4.Determine the current rates of escape of neutral gases and ions to space and the processes controlling them.
5.Determine the ratios of stable isotopes in the Martian atmosphere.
MAVEN reached Mars and successfully maneuvered into orbit around the planet on September 21, 2014.
Significance of the study:
1.MAVEN has made the first direct detection of the permanent presence of metal ions in the ionosphere of a planet other than Earth
2.Because metallic ions have long lifetimes and are transported far from their region of origin by neutral winds and electric fields, they can be used to infer motion in the ionosphere, similar to the way we use a lofted leaf to reveal which way the wind is blowing.
3.The metal comes from a constant rain of tiny meteoroids onto the red planet.
4.When a high speed meteoroid hits the Martian atmosphere, it vaporises. Metal atoms in the vapour trail get some of their electrons torn away by other charged atoms and molecules in the ionosphere, transforming the metal atoms into electrically charged ions.
5.MAVEN has detected iron, magnesium, and sodium ions in the upper atmosphere over the last two years, using its Neutral Gas and Ion Mass Spectrometer instrument, giving the team confidence that the metal ions are a permanent feature.
6.The interplanetary dust that causes the meteor showers is common throughout our solar system, so it is likely that all solar system planets and moons with substantial atmospheres have metal ions, according to the study
7.Sounding rockets, radar and satellite measurements have detected metal ion layers high in the atmosphere above the Earth.
8.There has also been indirect evidence for metal ions above other planets in the solar system.
9.When spacecraft are exploring these worlds from orbit, sometimes their radio signals pass through the planet’s atmosphere on the way to the Earth, and sometimes portions of the signal have been blocked.
This has been interpreted as interference from electrons in the ionosphere, some of which are thought to be associated with metal ions.
However, long term direct detection of the metal ions by MAVEN is the first conclusive evidence that these ions exist on another planet and that they are a permanent feature there.