NASA | GSFC | AGU | 2017 Apr 10
[img3="This artist concept shows the MAVEN spacecraft and the limb of Mars."MAVEN has made the first direct detection of the permanent presence of metal ions in the ionosphere of a planet other than Earth," said Joseph Grebowsky of NASA's Goddard Space Flight Center in Greenbelt, Maryland. "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." ...
Credit: NASA GSFC"]https://news.agu.org/files/2017/04/mave ... -small.jpg[/img3][hr][/hr]
The metal comes from a constant rain of tiny meteoroids onto the Red Planet. When a high-speed meteoroid hits the Martian atmosphere, it vaporizes. Metal atoms in the vapor 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.
MAVEN has detected iron, magnesium, and sodium ions in the upper atmosphere of Mars 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. ...
Unique, non-Earthlike, meteoritic ion behavior in upper atmosphere of Mars - J. M. Grebowsky et al
- Geophysical Research Letters (online 10 Apr 2017) DOI: 10.1002/2017GL072635 (pdf)
Mars’ Ionosphere: Cold, Lifeless, and Filled With Heavy Metals
Wired | 2017 Apr 11