NASA’s Mars Atmosphere and Volatile Evolution (MAVEN) mission studied the Crimson Planet’s ambiance for greater than a decade. Whereas contact was misplaced with the orbiter in December 2025, and the mission formally ended on June third, the information it gathered continues to enhance our understanding of Mars’ ambiance and the mechanics driving varied phenomena. This consists of Martian aurorae, that are just like what folks witness right here on Earth, however with some notable variations.
In a current examine, a crew led by researchers from the College of California, Berkeley, demonstrated that aurorae on Mars kind in a manner just like these on Earth. Based mostly on knowledge obtained by a number of of MAVEN’s scientific devices, they discovered that the identical mechanism that circulates charged photo voltaic particles from the Solar into Earth’s ambiance (the Dungey Cycle) additionally happens on Mars. Owing to the variations in our two planets’ magnetic fields, Martian aurorae happen on a lot smaller scales.
The paper describing their outcomes, “Miniature Dungey-like cycle at Mars,” appeared on July twenty third within the journal Nature Communications. The Dungey Cycle, named in honor of British area scientist James Dungey in 1961, describes the method that drives electrical currents in Earth’s magnetic subject, accelerates the charged photo voltaic particles that create auroras, and controls the circulation of plasma in Earth’s magnetosphere and higher ambiance.
Mars, the pink planet, has no magnetic subject to guard it from the photo voltaic wind, which means it loses its ambiance in a manner that Earth does not. Picture credit score: NASA/GSFC.
This course of begins when the Solar’s magnetic subject traces get near Earth’s magnetosphere, the place they reconnect and inject photo voltaic wind particles all through Earth’s magnetosphere and magnetotail. This results in the firing of electrons again into Earth’s ambiance, that are channeled in direction of the poles to generate aurorae. In contrast to Earth, Mars has no planet-wide magnetic subject, solely miniature magnetospheres that come up from intensely magnetized sections of crust scattered throughout the floor.
Earth’s personal subject is generated by a dynamo motion within the inside, the place a molten outer core counter-rotates with Earth round a stable interior core. On Mars, geological exercise within the core largely ceased about 4 billion years in the past, inflicting its magnetic subject to vanish. The magnetic areas are what’s left from the place lava cooled within the presence of this historical subject. The MAVEN mission has noticed extremely localized auroras over these fields, however it wasn’t till now that scientists totally understood the physics behind their formation.
To create a full image of the Dungey-like cycle on Mars, the crew consulted knowledge obtained by MAVEN’s Magnetometer, Solar Wind Electron Analyzer (SWEA), and Suprathermal and Thermal Ion Composition (STATIC) instrument. These devices have been used to find out the configuration of Mars’ magnetic fields, derive electrical currents, and measure plasma flows within the ionosphere, respectively.
Shaosui Xu, an affiliate analysis physicist on the Area Sciences Laboratory at UC Berkeley and the examine’s lead writer, defined in a NASA press release:
We knew that magnetic reconnection was occurring at Mars however didn’t anticipate it to be just like the Dungey cycle. We actually pushed the restrict of STATIC to get the information we wanted. It was the ultimate piece to the puzzle in understanding these localized auroras. I bear in mind in graduate college discussing with my advisor how the biking of crustal magnetic fields may work at Mars. It’s unbelievable to be a part of the crew that discovered the reply to that query.
A scientific visualization of the electrical currents round Mars (blue and pink arrows), exhibiting how they envelop Mars in a nested, double-loop construction from its day aspect to its evening aspect. Credit: NASA/Goddard/MAVEN/CU Boulder/SVS/Cindy Starr
The perception their work offers into what is occurring inside Mars’ crustal magnetic fields addresses the query of how electrons are being energized to create auroras.
By studying extra about this course of, scientists are additionally gaining a greater understanding of how area climate interacts with the Crimson Planet as a complete, which is important for future robotic and crewed missions. It lastly reveals {that a} Dungey-like mechanism can occur on each giant and small scales, offering clues about the place else within the Photo voltaic System this course of could possibly be happening.
Stated Shannon Curry, MAVEN’s principal investigator and a analysis scientist on the Laboratory for Atmospheric and Area Physics on the College of Colorado Boulder:
This can be a outstanding end result that modifications how we consider Martian auroras and is one other vital step towards understanding why Mars and Earth have advanced so in a different way regardless of being ruled by the identical underlying physics. I’m extremely pleased with our crew’s work on this discovery and excited to uncover new insights into the Crimson Planet and its evolution.
Additional Studying: NASA, Nature Communications
