Unusual Aurora Detected on Above Mars

  Using data collected from NASA's Mars Atmosphere and Volatile Evolution (MAVEN) orbiter, astronomers have spotted a new type of aurora on Mars. This aurora occurs primarily on the dayside of the Red Planet and is caused by an influx of protons.

  Using the Imaging Ultraviolet Spectrograph on MAVEN, astronomers noticed that sometimes the ultraviolet light emitted from hydrogen gas in Mars' upper atmosphere would temporarily brighten for a few hours. These bright events coincided whenever the orbiter detected an increase in solar-wind protons (charged particles emitted by the sun).

  Generally, Mars diverts these charged particles from the solar wind. However, the researchers noticed that on these bright occasions, some positively charged particles 'stole' electrons in order to become neutral and sneaked into the planet's upper atmosphere.
  "The Martian proton auroras are more than a light show," said Jasper Halekas, an associate professor in the Department of Physics and Astronomy at the University of Iowa. "They reveal that the solar wind is not completely diverted around Mars, by showing how solar wind protons can sneak past the bow shock and impact the atmosphere, depositing energy and even enhancing the hydrogen content there."

Read more about this fascinating story at: https://www.space.com/41261-stolen-electrons-spark-unusual-auroras-mars.html
Or read the full study here: https://www.nature.com/articles/s41550-018-0538-5

Image Credit: Dan Gallagher/NASA/MAVEN/Goddard Space Flight Center