Mars exhibits various aurora processes despite its thin atmosphere and absence of global magnetic fields. Previously, all aurora observations have been conducted in ultraviolet wavelengths from orbit. In a recent study, planetary scientists reported the observation of a green visible wavelength aurora, generated from the atomic oxygen line at 557.7 nanometers (nm), detected by NASA’s Perseverance rover using the Supercam and Mastcam-Z instruments.
The first visible image of the green aurora on Mars (left) taken by the NASA Perseverance rover’s Mastcam-Z instrument. On the right is a comparison image of the night sky on Mars without aurora, featuring the Moon Deimos on Mars. The moonlit Mars night sky, primarily illuminated by the larger moon Phobos (outside the frame), has a reddish-brown tint due to atmospheric dust. Consequently, the addition of green aurora light results in a green-yellow tone in the left image. Image credits: NASA/JPL-CALTECH/ASU/MSSS/SSI.
On Earth, auroras occur when solar particles interact with the magnetic field, colliding with atmospheric gases at the poles and emitting light.
Green, the most frequently observed color, results from excited oxygen atoms emitting light at a wavelength of 557.7 nm.
Researchers have theorized for years that green auroras could also manifest on Mars, but noted they would likely be more diffuse and harder to capture than those on Earth.
Due to the absence of a global magnetic field, Mars experiences a distinct type of aurora compared to Earth.
One such type is the Solar Energy Particle (SEP) Aurorae, identified by NASA’s Maven mission in 2014.
These auroras occur when high-energy particles from the sun impact the Martian atmosphere, leading to a luminous display in the night sky.
“Our findings open up new avenues for aurora research and affirm that future astronauts on Mars could witness these phenomena,” stated Dr. Ellis Knutsen, a postdoctoral researcher at the University of Oslo.
On March 15, 2024, the Sun’s solar flare production and the accompanying coronal mass ejection prompted auroras across the solar system, including Mars, with Perseverance capturing them for the first time from another planet’s surface.
Dr. Knutsen and his team utilized data from SEP instruments on NASA’s Maven spacecraft and ESA’s Mars Express spacecraft to verify the detection.
“They’re actively tracking this,” remarked Dr. Shannon Curry, a researcher at Maven and at the Institute of Atmospheric Astronomy at the University of Colorado, Boulder.
“We are thrilled to rapidly advance this observation and look forward to revealing what astronauts might see there.”
By correlating Perseverance’s observations with data from Maven’s SEP instrument, researchers can better analyze the detected 557.7 nm radiation from solar energy particles.
This emission line is identical to the green aurora on Earth, implying that future Mars astronauts may witness this type of aurora.
“The visibility of auroras from Perseverance enables new methods to study these phenomena, complementing orbital observations of Mars,” noted Dr. Katie Stack Morgan, the project scientist for Perseverance at NASA’s Jet Propulsion Laboratory.
“A deeper understanding of auroras and the conditions on Mars that facilitate their formation is crucial for preparing to send human explorers there safely.”
The team’s study was published in the journal Advances in Science.
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Elise W. Knutsen et al. 2025. Detection of the visible wavelength aurora on Mars. Advances in Science 11 (20); doi:10.1126/sciadv.ads1563
Source: www.sci.news
