NASA found out that the skies over Mars put up quite a show for at least half of the planet, but it’s a show very difficult to observe.
The one discovering the auroras is the Maven spacecraft. It spotted some events in the upper atmosphere of the Red Planet.
On Earth, our auroras are caused by electrons. On Mars, they are the result of protons, and scientists have just figured out how the events happen.
“Stolen” Electrons
Seeing Martian auroras was baffling for scientists. They then found out that protons could travel through the Red Planet’s magnetic ‘bow shock’ and light up the sky. But this event usually requires the presence of electrons.
Using the Imaging UltraViolet Spectrograph on board of the Maven spacecraft, scientists found ultraviolet light staying bright for many hours. The whole event happened when the Solar Wind Ion Analyzer saw a boost in solar wind protons.
NASA explains that this way, protons could behave like electrons by “stealing” them on their way towards Mars. Justin Deighan (the Laboratory for Atmospheric and Space Physics, University of Colorado) explains the event:
“The answer was thievery. As they approach Mars, the protons coming in with the solar wind transform into neutral atoms by stealing electrons from the outer edge of the huge clouds of hydrogen surrounding the planet. The bow shock can only divert charged particles, so these neutral atoms continue right on through.”
Sneaky Solar Wind Protons
Experts also found out that these proton auroras occur a lot more frequently on Mars than the auroras on our planet, which has a powerful magnetic field. When our auroras rarely happen, they appear in small regions close to the poles. On Mars, they can happen anywhere, and in large areas, said NASA.
Jasper Halekas of the University of Iowa added that this Martian phenomenon is more than just a “light show.” He explains that “solar wind protons can sneak past the bow shock and impact the atmosphere, depositing energy and even enhancing the hydrogen content there.”
Doris’s passion for writing started to take shape in college where she was editor-in-chief of the college newspaper. Even though she ended up working in IT for more than 7 years, she’s now back to what he always enjoyed doing. With a true passion for technology, Doris mostly covers tech-related topics.